hollow sphere polyaniline

-可编辑材料科学专业学术翻译必备词汇编号中文英文1合金alloy 2材料material 3复合材料properties 4制备preparation 5强度strength 6力学mechanical 7力学性能mechanical 8复合composite 9薄膜films 10基体matrix 11增强reinforced 12非晶amorphous 13基复合材料composites14纤维fiber 15纳米nanometer 16金属metal 17合成synthesis 18界面interface 19颗粒particles 20法制备prepared 21尺寸size 22形状shape 23烧结sintering 24磁性magnetic 25断裂fracture 26聚合物polymer 27衍射diffraction 28记忆memory 29陶瓷ceramic 30磨损wear 31表征characterization 32拉伸tensile 33形状记忆memory 34摩擦friction 35碳纤维carbon36粉末powder 37溶胶sol-gel 38凝胶sol-gel 39应变strain 40性能研究properties 41晶粒grain 42粒径size 43硬度hardness 44粒子particles 45涂层coating 46氧化oxidation 47疲劳fatigue 48组织microstructure49石墨graphite 50机械mechanical 51相变phase 52冲击impact 53形貌morphology 54有机organic 55损伤damage 56有限finite 57粉体powder 58无机inorganic 59电化学electrochemical 60梯度gradient 61多孔porous 62树脂resin 63扫描电镜sem 64晶化crystallization 65记忆合金memory 66玻璃glass 67退火annealing 68非晶态amorphous 69溶胶-凝胶sol-gel 70蒙脱土montmorillonite 71样品samples 72粒度size73耐磨wear 74韧性toughness 75介电dielectric 76颗粒增强reinforced 77溅射sputtering 78环氧树脂epoxy 79纳米tio tio 80掺杂doped 81拉伸强度strength 82阻尼damping 83微观结构microstructure84合金化alloying 85制备方法preparation 86沉积deposition87透射电镜tem 88模量modulus 89水热hydrothermal90磨损性wear 91凝固solidification 92贮氢hydrogen 93磨损性能wear 94球磨milling 95分数fraction 96剪切shear 97氧化物oxide 98直径diameter 99蠕变creep 100弹性模量modulus 101储氢hydrogen 102压电piezoelectric 103电阻resistivity 104纤维增强composites 105纳米复合材料preparation 106制备出prepared 107磁性能magnetic 108导电conductive109晶粒尺寸size 110弯曲bending 111光催化tio-可编辑112非晶合金amorphous 113铝基复合材料composites 114金刚石diamond 115沉淀precipitation 116分散dispersion 117电阻率resistivity 118显微组织microstructure119sic 复合材料sic 120硬质合金cemented 121摩擦系数friction 122吸波absorbing 123杂化hybrid 124模板template 125催化剂catalyst 126塑性plastic 127晶体crystal 128sic 颗粒sic 129功能材料materials 130铝合金alloy 131表面积surface 132填充filled 133电导率conductivity 134控溅射sputtering 135金属基复合材料composites 136磁控溅射sputtering 137结晶crystallization 138磁控magnetron 139均匀uniform 140弯曲强度strength 141纳米碳carbon 142偶联coupling 143电化学性能electrochemical 144及性能properties 145al 复合材料composite 146高分子polymer 147本构constitutive148晶格lattice 149编织braided150断裂韧性toughness 151尼龙nylon 152摩擦磨损性friction 153耐磨性wear 154摩擦学tribological 155共晶eutectic 156聚丙烯polypropylene 157半导体semiconductor158偶联剂coupling 159泡沫foam 160前驱precursor 161高温合金superalloy 162显微结构microstructure163氧化铝alumina 164扫描电子显微镜sem 165时效aging 166熔体melt 167凝胶法sol-gel 168橡胶rubber 169微结构microstructure170铸造casting 171铝基aluminum 172抗拉强度strength 173导热thermal 174透射电子显微镜tem 175插层intercalation 176冲击强度impact 177超导superconducting 178记忆效应memory 179固化curing 180晶须whisker 181溶胶-凝胶法制sol-gel 182催化catalytic 183导电性conductivity184环氧epoxy 185晶界grain 186前驱体precursor 187机械性能mechanical188抗弯strength 189粘度viscosity 190热力学thermodynamic 191溶胶-凝胶法制备sol-gel 192块体bulk 193抗弯强度strength 194粘土clay 195微观组织microstructure196孔径pore 197玻璃纤维glass 198压缩compression199摩擦磨损wear 200马氏体martensitic 201制得prepared 202复合材料性能composites 203气氛atmosphere 204制备工艺preparation205平均粒径size 206衬底substrate 207相组成phase 208表面处理surface 209杂化材料hybrid 210材料中materials 211断口fracture 212增强复合材料composites 213马氏体相变transformation214球形spherical 215混杂hybrid 216聚氨酯polyurethane 217纳米材料nanometer 218位错dislocation 219纳米粒子particles 220表面形貌surface 221试样samples 222电学properties 223有序ordered 224电压voltage-可编辑225析出phase 226拉伸性tensile 227大块bulk 228立方cubic 229聚苯胺polyaniline 230抗氧化性oxidation 231增韧toughening232物相phase 233表面改性modification234拉伸性能tensile 235相结构phase 236优异excellent 237介电常数dielectric 238铁电ferroelectric 239复合材料力学性能composites240碳化硅sic 241共混blends 242炭纤维carbon 243复合材料层composite 244挤压extrusion 245表面活性剂surfactant 246阵列arrays 247高分子材料polymer 248应变率strain 249短纤维fiber 250摩擦学性能tribological 251浸渗infiltration 252阻尼性能damping 253室温下room 254复合材料层合板composite 255剪切强度strength 256流变rheological257磨损率wear 258化学气相沉积deposition 259热膨胀thermal 260屏蔽shielding 261发光luminescence 262功能梯度functionally263层合板laminates 264器件devices 265铁氧体ferrite 266刚度stiffness 267介电性能dielectric268xrd 分析xrd 269锐钛矿anatase 270炭黑carbon 271热应力thermal 272材料性能properties 273溶胶-凝胶法sol-gel 274单向unidirectional275衍射仪xrd 276吸氢hydrogen 277水泥cement 278退火温度annealing 279粉末冶金powder 280溶胶凝胶sol-gel 281熔融melt 282钛酸titanate 283磁合金magnetic 284脆性brittle 285金属间化合物intermetallic 286非晶态合金amorphous 287超细ultrafine 288羟基磷灰石hydroxyapatite 289各向异性anisotropy 290镀层coating 291颗粒尺寸size 292拉曼raman 293新材料materials294tic 颗粒tic 295孔隙率porosity 296制备技术preparation 297屈服强度strength 298金红石rutile 299采用溶胶-凝胶sol-gel 300电容量capacity 301热电thermoelectric302抗菌antibacterial 303聚酰亚胺polyimide 304二氧化硅silica 305放电容量capacity 306层板laminates 307微球microspheres 308熔点melting 309屈曲buckling 310包覆coated 311致密化densification 312磁化强度magnetization313疲劳寿命fatigue 314本构关系constitutive 315组织结构microstructure 316综合性能properties 317热塑性thermoplastic 318形核nucleation 319复合粒子composite 320材料制备preparation 321晶化过程crystallization 322层间interlaminar 323陶瓷基ceramic 324多晶polycrystalline 325纳米结构nanostructures 326纳米复合composite 327热导率conductivity 328空心hollow 329致密度density 330x 射线衍射仪xrd 331层状layered 332矫顽力coercivity 333纳米粉体powder 334界面结合interface 335超导体superconductor 336衍射分析diffraction 337纳米粉powders 338磨损机理wear 339泡沫铝aluminum-可编辑340进行表征characterized 341梯度功能gradient 342耐磨性能wear 343平均粒particle 344聚苯乙烯polystyrene 345陶瓷基复合材料composites 346陶瓷材料ceramics 347石墨化graphitization348摩擦材料friction 349熔化melting 350多层multilayer 351及其性能properties 352酚醛树脂resin 353电沉积electrodeposition 354分散剂dispersant 355相图phase 356复合材料界面interface 357壳聚糖chitosan 358抗氧化性能oxidation 359钙钛矿perovskite 360分层delamination 361热循环thermal 362氢量hydrogen 363蒙脱石montmorillonite 364接枝grafting 365导率conductivity 366放氢hydrogen 367微粒particles 368伸长率elongation 369延伸率elongation 370烧结工艺sintering 371层合laminated 372纳米级nanometer 373莫来石mullite 374磁导率permeability375填料filler 376热电材料thermoelectric377射线衍射ray 378铸造法casting 379粒度分布size 380原子力afm381共沉淀coprecipitation 382水解hydrolysis 383抗热thermal 384高能球ball 385干摩擦friction 386聚合物基polymer 387疲劳裂纹fatigue 388分散性dispersion 389硅烷silane 390弛豫relaxation 391物理性能properties 392晶相phase 393饱和磁化强度magnetization 394凝固过程solidification 395共聚物copolymer 396光致发光photoluminescence 397薄膜材料films 398导热系数conductivity399居里curie 400第二相phase 401复合材料制备composites 402多孔材料porous 403水热法hydrothermal404原子力显微镜afm 405压电复合材料piezoelectric406尼龙6nylon 407高能球磨milling 408显微硬度microhardness 409基片substrate 410纳米技术nanotechnology 411直径为diameter 412织构texture 413氮化nitride414热性能properties 415磁致伸缩magnetostriction 416成核nucleation 417老化aging 418细化grain 419压电材料piezoelectric 420纳米晶amorphous421si 合金si 422复合镀层composite 423缠绕winding 424抗氧化oxidation 425表观apparent 426环氧复合材料epoxy 427甲基methyl 428聚乙烯polyethylene 429复合膜composite 430表面修饰surface 431大块非晶amorphous 432结构材料materials 433表面能surface 434材料表面surface 435疲劳性能fatigue 436粘弹性viscoelastic437基体合金alloy 438单相phase 439梯度材料material 440六方hexagonal 441四方tetragonal 442蜂窝honeycomb 443阳极氧化anodic 444塑料plastics 445超塑性superplastic446sem 观察sem 447烧蚀ablation 448复合薄膜films 449树脂基resin 450高聚物polymer 451气相vapor-可编辑452电子能谱xps 453硅烷偶联coupling 454团聚particles 455基底substrate 456断口形貌fracture 457抗压强度strength 458储能storage 459松弛relaxation 460拉曼光谱raman 461孔率porosity 462沸石zeolite 463熔炼melting 464磁体magnet 465sem 分析sem 466润湿性wettability 467电磁屏蔽shielding 468升温heating 469致密dense 470沉淀法precipitation471差热分析dta 472成功制备prepared 473复合体系composites 474浸渍impregnation 475力学行为behavior 476复合粉体powders 477沥青pitch 478磁电阻magnetoresistance 479导电性能conductivity480光电子能谱xps 481材料力学mechanical 482夹层sandwich 483玻璃化glass 484衬底上substrates 485原位复合材料composites 486智能材料materials 487碳化物carbide 488复相composite 489氧化锆zirconia490基体材料matrix 491渗透infiltration 492退火处理annealing 493磨粒wear 494氧化行为oxidation 495细小fine 496基合金alloy 497粒径分布size 498润滑lubrication 499定向凝固solidification500晶格常数lattice 501晶粒度size 502颗粒表面surface 503吸收峰absorption504磨损特性wear 505水热合成hydrothermal506薄膜表面films 507性质研究properties 508试件specimen 509结晶度crystallinity510聚四氟乙烯ptfe 511硅烷偶联剂silane 512碳化carbide 513试验机tester 514结合强度bonding 515薄膜结构films 516晶型crystal 517介电损耗dielectric 518复合涂层coating 519压电陶瓷piezoelectric520磨损量wear 521组织与性能microstructure 522合成法synthesis 523烧结过程sintering 524金属材料materials 525引发剂initiator 526有机蒙脱土montmorillonite527水热法制hydrothermal528再结晶recrystallization 529沉积速率deposition 530非晶相amorphous531尖端tip 532淬火quenching 533亚稳metastable 534穆斯mossbauer 535穆斯堡尔mossbauer 536偏析segregation 537种材料materials 538先驱precursor 539物性properties 540石墨化度graphitization541中空hollow 542弥散particles 543淀粉starch 544水热法制备hydrothermal545涂料coating 546复合粉末powder 547晶粒长大grain 548sem 等sem 549复合材料组织microstructure550界面结构interface 551煅烧calcined 552共混物blends 553结晶行为crystallization554混杂复合材料hybrid 555laves 相laves 556摩擦因数friction 557钛基titanium 558磁性材料magnetic 559制备纳米nanometer 560界面上interface 561晶粒大小size 562阻尼材料damping 563热分析thermal 564复合材料层板laminates 565二氧化钛titanium-可编辑566沉积法deposition567光催化剂tio 568余辉afterglow 569断裂行为fracture 570颗粒大小size 571合金组织alloy 572非晶形成amorphous 573杨氏模量modulus 574前驱物precursor 575过冷alloy 576尖晶石spinel 577化学镀electroless 578溶胶凝胶法制备sol-gel 579本构方程constitutive 580磁学magnetic 581气氛下atmosphere 582钛合金titanium 583微粉powder 584压电性piezoelectric585sic 晶须sic 586应力应变strain 587石英quartz 588热电性thermoelectric589相转变phase 590合成方法synthesis 591热学thermal 592气孔率porosity 593永磁magnetic 594流变性能rheological 595压痕indentation 596热压烧结sintering 597正硅酸乙酯teos 598点阵lattice 599梯度功能材料fgm 600带材tapes 601磨粒磨损wear 602碳含量carbon 603仿生biomimetic 604快速凝固solidification605预制preform 606差示dsc 607发泡foaming 608疲劳损伤fatigue 609尺度size 610镍基高温合金superalloy 611透过率transmittance 612溅射法制sputtering 613结构表征characterization 614差示扫描dsc 615通过sem sem 616水泥基cement 617木材wood 618tem 分析tem 619量热calorimetry 620复合物composites 621铁电薄膜ferroelectric 622共混体系blends 623先驱体precursor 624晶态crystalline 625冲击性能impact 626离心centrifugal 627断裂伸长率elongation 628有机-无机organic-inorganic 629块状bulk 630相沉淀precipitation631织物fabric 632因数coefficient 633合成与表征synthesis 634缺口notch 635靶材target 636弹性体elastomer 637金属氧化物oxide 638均匀化homogenization 639吸收光谱absorption640磨损行为wear 641高岭土kaolin642功能梯度材料fgm 643滞后hysteresis 644气凝胶aerogel 645记忆性memory 646磁流体magnetic 647铁磁ferromagnetic648合金成分alloy 649微米micron 650蠕变性能creep 651聚氯乙烯pvc 652湮没annihilation 653断裂力学fracture 654滑移slip 655差示扫描量热dsc 656等温结晶crystallization 657树脂基复合材料composite 658阳极anodic 659退火后annealing 660发光性properties 661木粉wood 662交联crosslinking 663过渡金属transition 664无定形amorphous 665拉伸试验tensile 666溅射法sputtering 667硅橡胶rubber 668明胶gelatin 669生物相容性biocompatibility 670界面处interface 671陶瓷复合材料composite 672共沉淀法制coprecipitation 673本构模型constitutive674合金材料alloy 675磁矩magnetic 676隐身stealth 677比强度strength 678改性研究modification 679采用粉末powder-可编辑680晶粒细化grain 681抗磨wear 682元合金alloy 683剪切变形shear 684高温超导superconducting 685金红石型rutile 686晶化行为crystallization 687催化性能catalytic 688热挤压extrusion 689微观microstructure690tem 观察tem 691缺口冲击impact 692生物材料biomaterials 693涂覆coating 694纳米氧化nanometer695x 射线光电子能谱xps 696硅灰石wollastonite 697摩擦条件friction 698衍射峰diffraction699块体材料bulk 700溶质solute 701冲击韧性impact 702锐钛矿型anatase 703凝固组织microstructure704磨损试验机tester 705丙烯酸甲酯pmma 706raman 光谱raman 707减振damping 708聚酯polyester 709体材料materials 710航空aerospace 711光吸收absorption 712韧化toughening 713疲劳裂纹扩展fatigue 714超塑superplastic715凝胶法制备gel716半导体材料semiconductor717剪应力shear 718发光材料luminescence719凝胶法制gel 720甲基丙烯酸甲酯pmma 721硬质hard 722摩擦性能friction 723电致变色electrochromic724超细粉powder 725增强相reinforced 726薄带ribbons 727结构弛豫relaxation 728光学材料materials729sic 陶瓷sic 730纤维含量fiber 731高阻尼damping 732镍基nickel 733热导thermal 734奥氏体austenite 735单轴uniaxial 736超导电性superconductivity 737高温氧化oxidation 738树脂基体matrix 739含能energetic 740粘着adhesion 741穆斯堡尔谱mossbauer 742脱层delamination 743反射率reflectivity 744单晶高温合金superalloy 745粘结bonded 746快淬quenching 747熔融插层intercalation 748外加applied 749钙钛矿结构perovskite 750减摩friction 751复合氧化物oxide 752苯乙烯styrene 753合金表面alloy 754爆轰detonation755长余辉afterglow 756断裂过程fracture 757纺织textile。

Home Search Collections Journals About Contact us My IOPscienceA highly porous NiO/polyaniline composite film prepared by combining chemical bathdeposition and electro-polymerization and its electrochromic performanceThis article has been downloaded from IOPscience. Please scroll down to see the full text article.2008 Nanotechnology 19 465701(/0957-4484/19/46/465701)View the table of contents for this issue, or go to the journal homepage for moreDownload details:IP Address: 202.120.113.7The article was downloaded on 18/09/2011 at 09:08Please note that terms and conditions apply.IOP P UBLISHING N ANOTECHNOLOGY Nanotechnology19(2008)465701(7pp)doi:10.1088/0957-4484/19/46/465701A highly porous NiO/polyaniline compositefilm prepared by combining chemical bath deposition andelectro-polymerization and its electrochromic performanceX H Xia1,J P Tu1,J Zhang1,X L Wang1,W K Zhang2andH Huang21Department of Materials Science and Engineering,Zhejiang University,Hangzhou310027,People’s Republic of China2College of Chemical Engineering and Materials Science,Zhejiang University of Technology,Hangzhou310032,People’s Republic of ChinaE-mail:tujp@Received28August2008,infinal form19September2008Published22October2008Online at /Nano/19/465701AbstractA highly porous NiO/polyaniline(PANI)compositefilm was prepared on ITO glass bycombining the chemical bath deposition and electro-polymerization methods,successively.Theporous NiOfilm acts as a template for the preferential growth of PANI along NiOflakes,andthe NiO/PANI compositefilm has an intercrossing net-like morphology.The electrochromicperformance of the NiO/PANI compositefilm was investigated in1M LiClO4+1mMHClO4/propylene carbonate(PC)by means of transmittance,cyclic voltammetry(CV)andchronoamperometry(CA)measurements.The NiO/PANI thinfilm exhibits a noticeableelectrochromism with reversible color changes from transparent yellow to purple and presentsquite good transmittance modulation with a variation of transmittance up to56%at550nm.The porous NiO/polyaniline(PANI)compositefilm also shows good reaction kinetics with fastswitching speed,and the response time for oxidation and reduction is90and110ms,respectively.1.IntroductionElectrochromic materials present a reversible change in optical properties when they are electrochemically oxidized or reduced[1].These materials include transition oxides, inorganic coordination complexes,organic molecules,con-ducting conjugated polymers and so on[2].Early studies of electrochromism mainly focus on inorganic and small-molecule organic electrochromes,which suffer from process-ing,compatibility and performance problems.More recently, electrochromic research has heavily focused on electrochromic conducting polymerfilms because of their high color contrast, multiple color possibilities,rapid response times and ease of processing[3–5].A primary advantage that conducting polymers hold over inorganic electrochromic materials is their fast electrochromic response,which is controlled by the diffusion of counter-ions into the electrochromic materials[5]. The ion-intercalation reaction is limited both by the diffusion coefficient and by the length of the diffusion path.The former depends on the molecular structure of the material,while the latter is determined by the microstructure of the material[6].A molecular-level approach to improve response time is the rational design and synthesis of novel electrochromic polymers with fast electrochromic response[7].Meanwhile,an alternative approach is to fabricatefilms with a highly porous structure,which can provide a very short diffusion pathway for the counter-ions as well as a large active surface.Some porous electrochromicfilms have been successfully prepared andexhibited improved electrochromic performance.For example, poly(3,4-ethylenedioxythiophene)(PEDOT)nanotubes were electrochemically synthesized on an ITO substrate in the AAO nanopores[8],which exhibited fast color changes with50and 70ms response times for oxidation and reduction,respectively. Therefore,constructing a porous structure is an effective way to improve response time.Polyaniline(PANI),a unique conjugated polymer,has been extensively studied as a promising polyelectrochromic material exhibiting three main stable oxidation states:the fully reduced leucoemeraldine(LE)form(transparent yellow), the50%oxidized emeraldine salt(ES)form(green)and the fully oxidized pernigraniline form(purple)[9].The PANI can be prepared by a chemical or an electrochemical oxidative polymerization,in which the electro-polymerization is believed to be the most simple and convenient method for preparation of the PANIfilm[10].Nevertheless,the adherence of the PANfilm on ITO glass is very weak and it can be easily rinsed out from the substrate.A lot of work has been devoted to improving the mechanical strength andflexibility of a PANIfilm on ITO glass.Several insulated polymers such as PV A and poly(4-styrenesulfonate)were selected to act as a template for electro-deposition of PANIfilms[11,12]. The adherence was found to have dramatically improved. Nonetheless,these template materials are insulated polymers, which always decrease the response speed.To overcome this shortcoming,a porous conductingfilm will be a good candidate for the supporting matrix.It can act as a solid support without sacrificing response time due to the porous structure,which can provide good pathways for electron transfer and ion diffusion at the same time.Template synthesis is one of the most commonly used methods to fabricate highly porous structures.A variety of porous conducting polymers including PANI,PEDOT and polypyrrole have been synthesized using porous AAO and track-etched polycarbonate membranes[8,13–15].The object materials could be deposited into nanosized template pores to form nanotubes or nanowires.However,to date,there are few reports on the electrochromic performance of porous PANI films.Recently,we have pioneered the electrochromics of highly porous NiO with pore diameters ranging from50to 250nm[16].The porous NiOfilm has high transparency and electrochromic performance,which is important for electrochromic devices.These results provide the impetus for the application of the highly porous NiO as a template to synthesize porous materials.Up to now,there are only a few reports on the synthesis of NiO/PANI composites.NiO/PANI nanobelt and NiO/PANI rectangular tube powders have been successfully synthesized via chemical polymerization by the group of Guo[17,18].Additionally,Peng et al[19] reported that a NiO x/PANI compositefilm,used as a catalyst towards electro-oxidation of polyhydroxyl compounds,could be prepared by electro-deposition in a neutral aqueous solution. Actually,the compositefilm prepared by Peng et al[19] is Ni(OH)2/PANI,not NiO/PANI.In a recent study,our group reported a porous NiO/PANI composite on a foam nickel substrate for Li-ion anode material,but the possible formation mechanism was not discussed[20].Combining the electrochromic capabilities of PANI and highly porous NiO in a compositefilm is an attractive goal and has not been explored.In this present work,the highly porous NiOfilm was used as a template to prepare highly porous net-like NiO/PANI compositefilms on an ITO substrate by combining chemical bath deposition and electro-polymerization,successively.The microstructure,formation mechanism and electrochromic performances of this porous NiO/PANI compositefilm were also investigated.2.Experimental details2.1.Chemical materialsAll chemical reagents were AnalaR(AR)grade.Nickel sulfate (NiSO4·6H2O),aqueous ammonia(25–28%),potassium persulfate(K2S2O8),perchloric acid(HClO4),lithium perchlorate(LiClO4)and propylene carbonate(99.9%)were obtained from Shanghai Chemical Reagent Co.All aqueous solutions were freshly prepared using high purity water (18M cm resistance).2.2.Preparation of highly porous NiOfilmThe synthesis routes for highly porous NiOfilms have already been described in detail in our previous work[16]and thus will only be briefly described here.Clean ITO glass substrates 2.5×2.5cm2in size were placed vertically in the freshly deposition solution containing80ml of1M nickel sulfate, 60ml of0.25M potassium persulfate and20ml of aqueous ammonia(25–28%).After stirring for20min,the substrate was removed from the solution and washed with distilled water. Finally,the as-prepared sample was annealed at300◦C for 1.5h.The thickness of the NiOfilm was approximately 480nm,determined with Alpha-step200profilometry.2.3.Preparation of highly porous NiO/PANI compositefilm Aniline was distilled under reduced pressure and stored in the sealed state at4◦C.The electrolyte for the electro-polymerization of PANI was obtained by dissolving1ml aniline in100ml of0.01M H2SO4solution.The electro-polymerization of PANI was carried out in a three-compartment system,with the above porous NiO thinfilm electrode as the working electrode,a saturated calomel electrode(SCE)as the reference electrode and a Pt foil as the counter-electrode.The PANIfilm was deposited by cyclic voltammetry as follows:thefirst cycle was conducted in the potential range of−0.2–1.3V with a sweep rate of 50mV s−1.The subsequent10cycles were carried out in the potential range of−0.2–1.0V with a sweep rate of50mV s−1. Calculated from the weight increment,the content of PANI in the compositefilm was20wt%.2.4.CharacterizationThe morphology and microstructure of samples were char-acterized by afield emission scanning electron microscope (FESEM,Hitachi S-4700),a transmission electron microscopeFigure1.Cyclic voltammetric curves of electro-polymerization of PANI on the NiOfilm.(TEM,JEM-2010),x-ray diffraction(XRD,Philips PC-APDwith Cu Kαradiation)and Fourier-transform infrared(FTIR) measurements(Perkin-Elmer System2000FTIR interferom-eter).The cyclic voltammetry(CV),chronoamperometry(CA)and electrochemical impedance spectroscopy(EIS)measurements of the NiO/PANIfilm were carried out in athree-compartment system containing1M LiClO4+1mM HClO4/propylene carbonate(PC)as the electrolyte,a saturatedcalomel electrode(SCE)as the reference electrode and a Ptfoil as the counter-electrode on a CHI760B ElectrochemicalWorkstation(Chenhua,Shanghai).The CV measurementswere carried out in the potential range of−0.2–1.0V with a scanning rate of50mV s−1at room temperature(25±1◦C). Thefilm electrodes,0.5×1.0cm2in size,were used for electrochemical impedance spectroscopy(EIS)measurements, which were made with a superimposed5mV sinusoidal voltage in the frequency range of100kHz–0.01Hz.The transmission spectra of NiO/PANIfilms in different redox states were measured over the range from200to900nm with a Shimadzu UV-240spectrophotometer.Each spectrum was recorded ex situ(after the samples were taken out of the three-compartment system,instantly rinsed and wiped to remove the remaining persistent solution).N2adsorption was determined by BET(Brunauer–Emmett–Teller)measurements using a NOV A-1000e surface area analyzer.3.Results and discussion3.1.Electro-deposition and structure characterization Figure1shows the cyclic voltammograms(CVs)of electro-deposition of PANIfilms on the porous NiOfilm.The CVs exhibits three pairs of redox peaks,which are similar to those reported by other authors[21,22].The increasing current with each cycle reflects the growth of the polymer film.Thefirst redox couple A1/C1is ascribed to the oxidation of leucoemeraldine to emeraldine salt[23].The second redox couple A2/C2is due to the degradation of radicals to benzoquinone during polymerization and has been assigned to the branched structure of PANI[24,25].The third redox couple A3/C3corresponds to the conversion fromemeraldine Figure2.XRD patterns of(a)NiOfilm and(b)NiO/PANI compositefilm on ITOglass.Figure3.FTIR spectra of powders from(a)NiOfilm and(b)NiO/PANI compositefilm.base to pernigraniline structure.The A4peak is attributed to the nucleation of aniline,which is similar to the previous report[26].The XRD patterns of NiO and NiO/PANI compositefilms on ITO substrates are presented infigure2. The diffraction peaks of both samples can be indexed as cubic NiO phase(JCPDS4-0835).No obvious diffraction peaks of PANI are observed,indicating the amorphous nature of PANI deposited by the CVs.Figure3shows the FTIR absorption spectra of powders from thefilms on ITO substrates.For the NiOfilm,a strong band centered at418cm−1[27]corresponding to the stretching vibration of NiO is presented in spectrum a.A broad OH band centered at3420cm−1is indicative of hydrogen-bonded water within thefilm structure.The bands in the spectral region of 900–1150cm−1belong to sulfate groups(SO2−4)[28].The band at587cm−1corresponds toδ(OH).For the NiO/PANI film,a broad band at3180–3480cm−1is observed,which is assigned to the stretching vibration NH of an aromatic amine as well as the stretching vibration of absorbed water.The bands centered at1578and1487cm−1are due to the C=C stretching vibrations of a quinoid(Q)ring and benzenoid ring,respectively[29].The band centered at1306cm−1is assigned to the C–N stretching band of an aromatic amine.The characteristic band of the PANI base is the N=Q=N stretchingFigure4.SEM and TEM micrographs of(a),(b)NiOfilm and(c), (d)NiO/PANI compositefilm.band at1130cm−1and a820cm−1band to an aromatic CH out-of-plane bending[30].The band at587cm−1corresponds to the bending vibration of OH.A strong band characteristic of NiO at418cm−1is also observed.Therefore,both FTIR and XRD results are in complete agreement and show an effective formation of the NiO/PANIfilm.The SEM and TEM images of NiO and NiO/PANI compositefilms are shown infigure4.The NiOfilm has a structure with huge porosity.The diameters of the pores range from50to250nm.The interconnecting network is made up offlaky nickel oxides with thicknesses of30–50nm,which Figure5.BET measurements of(a)NiOfilm and(b)NiO/PANI compositefilm.is similar to that reported by Wu et al[31].The NiO/PANI compositefilm maintains the highly porous net-like structure, but the thickness of theflakes becomes thicker,ranging from70 to90nm.In addition,the diameter of pores of the NiO/PANI film is much smaller than that of the NiOfilm,ranging from25 to110nm.BET measurements(figure5)show that the surface area of porous NiO and NiO/PANIfilms is350and485m2g−1, respectively.The pore size distributions of bothfilms show peaks at150and70nm,respectively.The porous NiO template has a porosity of about86%.After electro-polymerization,the porosity of the NiO/PANIfilm decreases but is still high up to 60%.From the TEM images offlakes of NiO and NiO/PANI compositefilms,it is noticed that these twoflakes have distinct surface morphology.Theflake before electro-polymerization is thin andflat with low roughness,while theflake after electro-polymerization is much thicker with a very rough appearance. It is inferred that the NiOflake is enwrapped by the PANI, which means that the compositeflake is composed of two parts: the inner layer is NiO and the outer layer is PANI.Based on the above results,a plausible formation mechanism of an NiO/PANI compositefilm could be described as follows:the porous NiOfilm acts as a template for PANI growth during the electro-polymerization,leading to the preferential growth of PANI along NiOflakes.The electro-polymerization ofITOGlassPANINiOChemical bath depositionE le ct r o-d ep os i ti o nFigure 6.Schematic diagram of fabricating porous NiO/PANI composite films on an ITO substrate.PANI first occurs along the NiO flakes and protects them from dissolving in an acid solution.The schematic for the synthesis of porous NiO/PANI composite films on ITO glass is illustrated in figure 6.The reason that the PANI preferentially nucleates and grows along NiO flakes may be due to the solvophobic and electrostatic interactions [14,15].On the one hand,the aniline is soluble,but the PANI is completely insoluble.Hence,there is a solvophobic component to the interaction between the PANI and the NiO flake.On the other hand,there is also an electrostatic component to the interaction between the nascent PANI and the NiO flake.This is because the PANI is cathodic,and there are anionic sites on the NiO flakes.As a result,the two factors contribute to the PANI preferentially nucleating and growing along NiO flakes and the formation of porous NiO/PANI films.3.2.Electrochromic and electrochemical propertiesThe electrochromism of PANI is closely related to its unique redox doping/dedoping processes,which can be easily controlled by applying electrical potentials.The transmittance spectra of the NiO/PANI composite film under six different applied potentials are shown in figure 7,and the photographs of a sample on the corresponding states are shown in figure 8.It is clearly seen that the NiO/PANI film presents a noticeable electrochromism with reversible color changes from transparent pale yellow to purple when the potential is varied from −0.2to 1.0V .It is observed that the transmittance decreases and the transmittance edges show a blueshift to the ultraviolet region as the applied potential increases from −0.2to 0.7V .While the PANI is oxidized into the totally pernigraniline structure (purple),the transmittance increases in the near-infrared region.This phenomenon is in accordance with the result in the literature [32].The transmittance variation between leucoemeraldine and pernigraniline states is up to 56%at 550nm.This value is comparable with the result obtained by Wang et al [33].The electrochromic response is an important criterion for selecting an electrochromic material.In this case,the porous NiO/PANI composite film was switched from an oxidized state to a reduced state by applying alternating square potentials between 0.8and −0.2V (versus SCE).Figure 9shows the resultant current–time response.The response times for oxidation and reduction are 90and 110ms,respectively.TheFigure 7.Optical transmittance spectra of NiO/PANI composite film s under six different appliedpotentials.Figure 8.Photographs of a sample with a size of 2.5×2.5cm 2under different applied potentials.switching speeds are much slower than those obtained by Lacroix et al (100μs)[34],but better than the result of Ram et al (205ms)[35].The response time is dependent on several factors such as applied potential,film thickness and electrolyte conductivity.The PANI film obtained by Lacroix et al is much thinner (120nm)and tested in 2M H 2SO 4.The thin film prepared by Ram et al is about 400nm and tested in 1M HCl.Our sample is about 480nm and tested in 1M LiClO 4+1mM HClO 4/PC,which has lower electrolyte conductivity.Nevertheless,the NiO/PANI film still exhibits a much faster electrochromic response than the conventional PANI film (>500ms)[36]and inorganic electrochromic materials (>1s).This is mainly due to the highly porous structure.The electrochromic processes involve double injection (extraction)of ions and electrons into (from)the film.The processes are believed to first occur at grain boundaries and on grain surfaces.The highly porous structure of the NiO/PANI composite film provides a large reaction surface and inner space,which facilitate electrolyte penetration into the film and shorten diffusion pathways for the counter-ions.Meanwhile,the intercrossing network provides much more paths for the double injection (extraction)of ions and electrons into (from)the film.All these contribute to the improvement of response speed.Figure9.Chronoamperometric curve of the porous NiO/PANI compositefilm.The electrochemical stability of the NiO/PANIfilm in1M LiClO4+1mM HClO4/PC was typically characterized by cyclic voltammetry in the potential range of−0.2–0.8V,at a sweep rate of50mV s−1.The evolution of CVs of the NiO/PANIfilm is shown infigure10.There is a significant shift in the shape of the recorded curves.The CV curve at thefirst cycle shows three typical redox couples.The first redox couple P1/C1corresponds to the change between leucoemeraldine base(LB)and emeraldine salt(ES)with anion doping upon oxidation and dedoping upon reduction,which can be simply expressed as follows[33,37]:PANI+n ClO−14 (LB,yellow)⇔(PANI n+)(ClO−14)n+n e−1(ES,green)(1)The second redox couple P2/C2has been attributed to the redox reactions of degradation products of PANI,including benzoquinone and quinoneimines[24,25,38,39].The redox couple P3/C3is due to the conversion between emeraldine base (EB)and pernigraniline salt(PS)with doping/dedoping of the anion processes,represented by the following reaction[33,37]:EB+m ClO−14 (EB,blue)⇔(EB m+)(ClO−14)m+m e−1.(PS,purple)(2)The conversion between ES and EB is due to protonation/deprotonation processes illustrated as follows:ES (Green)⇔EB+n ClO−14+n H+.(Blue)(3)No electrochemical current peaks of NiO are observed in this potential range.It indicates that the PANI plays a leading role in this potential range for electrochromism,and the NiO mainly plays the role of support.From CV results,an obvious degradation has been observed.After200cycles,the peak P2 starts to merge with the peak P3.The peaks C2and C3merge together at the800th cycle.Up to the103th cycle,only one redox couple can be seen.The current decreases dramatically and presents a fading of about60%at the103cycle.Similar phenomena for PANI electrochemical degradation havealso Figure10.Cyclic voltammogram of NiO/PANI compositefilm in1M LiClO4+1mM HClO4/PC at a sweep rate of50mV s−1. been observed by others[24,25].The cycling stability ofthe NiO/PANIfilm in the present system has been found tobe less than103cycles on going from the reduced state to theoxidized state in the potential range of−0.2–0.8V.The result is much lower than the value of106cycles,as observed byKobayashi et al[40]for a1.0μm PANI thinfilm on switching between leucoemeraldine and emeraldine salt.The shorterlifetime is due to the degradation of the pernigraniline and NiOchemical instability in the electrolyte solution for a prolongedtime.It is believed that the pernigraniline is not stable as aresult of benzoquinone formation by hydrolysis during cycling,especially under a potential higher than0.7V(versus SCE).Onthe other hand,these degradation products are soluble in theelectrolyte and peel off from thefilm electrode during cycling.As mentioned above(figure4),the NiOflake is enwrapped byPANI.When the PANI degrades and peels off,the NiO will beexposed to the acid electrolyte and dissolve.This leads to thebreakdown of the NiO backbone and results in worse stability.Figure11shows EIS plots of NiO and NiO/PANIcompositefilms and an equivalent circuit model.Both Nyquistplots are recorded in1M LiClO4+1mM HClO4/PC after both samples have been subjected to a step voltage of0.6Vfor5s.The impedances of bothfilm electrodes consistof a depressed arc in high frequency regions and a straightline in low frequency regions.Generally,the semicirclereflects the electrochemical reaction impedance(Rct)of thefilm electrode and the straight line represents the diffusionof electroactive species(Rw).Compared to the NiOfilm,the NiO/PANIfilm exhibits a much smaller capacitive arcand slower slope.According to previous reports[41–43],a larger semicircle means a larger charge transfer resistanceand smaller electrochemical capacitance(Qc),and a higherslope signifies a lower diffusion rate.It is concluded thatthe NiO/PANIfilm has much lower charge transfer resistanceand ion diffusion resistance as well as larger electrochemicalcapacitance than the NiOfilm,indicating the compositefilmis favorable for charge transfer and ion diffusion.This is dueto the porous conductive network formed by the PANI.It iswell known that the PANI exhibits high electrical conductivityFigure11.EIS plots of bothfilm electrodes.in the partially oxidized state.In our experiment,a uniform PANIfilm is deposited on the NiOfilm after electrochemical polymerization,which provides a good conductive network for the whole compositefilm.On the other hand,the highly porous structure of the NiO/PANIfilm provides a large reaction surface and inner space,facilitating ion diffusion.4.ConclusionThe highly porous NiO/PANI compositefilm was successfully prepared by combining the chemical bath deposition and electro-polymerization methods,successively.It is expected that this synthetic method may be applicable for the synthesis of other inorganic material–conducting polymer composite films.The as-prepared NiO/PANI compositefilm has a net-like structure with huge porosity.The NiOfilm acts as a template for the preferential growth of PANI along NiOflakes.The NiO flakes are coated by PANI and protected from dissolving in an acidic environment.The NiO/PANI compositefilm exhibits a noticeable electrochromism with reversible color changes from pale yellow to purple.The NiO/PANI compositefilm presents quite a good transmittance modulation with a variation of transmittance up to56%at550nm.In addition,the NiO/PANI compositefilm electrode exhibits quite good reaction kinetics with fast switching speed due to its highly porous structure. 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化工进展Chemical Industry and Engineering Progress2024 年第 43 卷第 4 期具有烷基磺酸侧链的凝胶型聚苯并咪唑质子交换膜的制备与表征朱泰忠1，张良1，黄泽权1，罗伶萍1，黄菲1，薛立新1，2（1 浙江工业大学化工学院膜分离与水科学技术中心，浙江 杭州 310014；2温州大学化学与材料工程学院，浙江 温州 325035）摘要：磷酸（PA ）掺杂聚苯并咪唑（PBI ）以其优异的热化学稳定性和高玻璃化转变温度成为高温质子交换膜燃料电池（HT-PEMFCs ）的首选材料。

然而，由于低温下磷酸较弱的解离度和传递速率，导致膜的质子传导性能不佳，电池冷启动困难。

因此，研发可在宽温湿度范围内高效运行的高温质子交换膜成为当前挑战。

特别是拓宽其低温运行窗口、实现冷启动对这类质子交换膜燃料电池在新能源汽车领域的实际应用具有重要意义。

本文通过多聚磷酸溶胶凝胶工艺与内酯开环反应设计并合成了一系列磷酸掺杂的具有柔性烷基磺酸侧链的凝胶型聚苯并咪唑质子交换膜。

重点探究了烷基磺酸的引入以及侧链长度对磷酸掺杂水平、不同温湿度下的质子传导率及稳定性的影响规律。

研究结果表明，所制备的质子交换膜具有凝胶型自组装片层堆叠的多孔结构，有利于吸收大量磷酸并提供质子快速传输通道。

其中，PA/PS-PBI 展现出了在宽温域范围内均优于目前所报道的其他工作的质子传导性能。

特别是常温下，其质子传导率从原膜的0.0286S/cm 提升至0.0694S/cm 。

80℃下，其质子传导率从原膜的0.1117S/cm 提升至0.1619S/cm 。

200℃下，其质子传导率从原膜的0.2609S/cm 提升至0.3578S/cm 。

此外，该膜在80℃和0%相对湿度（RH ）条件下仍可具有与Nafion 膜在100%RH 时相当的质子传导率，为打破质子交换膜经典定义、实现宽温域（25~240℃）运行提供新的方案。

Facile synthesis of Mn 2O 3hollow and core–shellcube-like nanostructures and their catalyticpropertiesLing Liu a ,b ,⇑,Xiaojun Zhang c ,Ruiyu Wang a ,b ,Jianzhou Liu caKey Laboratory of Coal-Based CO 2Capture and Geological Storage of Jiangsu Province,China University of Mining and Technology,Xuzhou 221008,People’s Republic of Chinab Low Carbon Energy Institute,China University of Mining and Technology,Xuzhou 221008,People’s Republic of Chinac School of Chemical Engineering and Technology,China University of Mining and Technology,Xuzhou 221116,People’s Republic of China a r t i c l e i n f o Article history:Received 26March 2014Accepted 28March 2014Available online 16April 2014Keywords:Hollow nanostructures Growth from solutions Manganese oxides Nanomaterials Catalysisa b s t r a c tManganese carbonate (MnCO 3)hollow cube-like nanostructureswere synthesized via a facile polyol process and then thermal con-verted to phase-pure manganese oxide (Mn 2O 3).Based on thestructural analysis of MnCO 3precursor obtained at differentreaction times,a mechanism of inside-out Ostwald ripening wasproposed to account for the formation of the hollow nanostruc-tures.An annealing treatment at 500°C with a ramping rate of3°C min À1was utilized to convert the MnCO 3precursor intoMn 2O 3.The manganese oxide powder products possessed mesopo-rosity and essentially preserved the pristine morphology of theMnCO 3precursor.The products were characterized by X-ray pow-der diffraction (XRD),and field-emission scanning electron micros-copy (FESEM),transmission electron microscopy (TEM),Fouriertransform infrared spectrometry (FT-IR),Thermal gravimetric ana-lyze (TGA),X-ray photoelectron spectroscopy (XPS),and Brunauer–Emmett–Teller (BET).Furthermore,relative to Mn 2O 3core–shellcube-like microstructures,the mesoporous hollow cubes exhibiteda higher catalytic activity towards CO oxidation.Ó2014Elsevier Ltd.All rights reserved./10.1016/j.spmi.2014.03.0500749-6036/Ó2014Elsevier Ltd.All rights reserved.⇑Corresponding author at:Low Carbon Energy Institute,China University of Mining and Technology,Xuzhou 221008,People’s Republic of China.Tel.:+8651683883196;fax:+8651683883501.E-mail address:liulingsd@ (L.Liu).220L.Liu et al./Superlattices and Microstructures72(2014)219–2291.IntroductionRecently,inorganic hollow micro/nanostructures with remarkable interior space have attracted considerable attention owing to a wide range of applications in chemical reactors,drug delivery,catal-ysis and sensors[1–4].Because the properties of hollow structures could be tuned by tailoring their shape and crystallization,there has been increasing interest in the controlling synthesis of hollow structures with non-spherical morphologies such as polyhedra,ellipsoids and pared to spherical counterparts,the synthesis of hollow structures with well-defined non-spherical shapes remained a significant challenge to materials scientists[5].Soft templates such as surfactant micelles and emulsion droplets,do not assume well-defined non-spherical shapes in order to minimize the interfacial energy.Even with hard templates,preparation of non-spherical hollow structures intro-duces additional challenges.These range from the difficulty in forming a uniform coating around sur-faces with large variation in curvature to the paucity of available non-spherical templates for the synthesis.Due to these difficulties,reports on synthesis of non-spherical hollow structures are rare. Thus,the search for template-free,simple,mild,high-yield and environmentally friendly methods to synthesize different inorganic hollow structures is still a significant challenge.In the past decade, various physical phenomena such as oriented attachment[6],Ostwald ripening[7]and Kirkendall effect[8]have been employed in a number of one-pot template-free methods for fabrications of hol-low inorganic nanostructures.Among them,mass transport via Ostwald ripening has been proven to be a facile approach to generate symmetric and/or asymmetric interior spaces for inorganic nanostruc-tures[9–11].Manganese oxides have been the subject of fascinating interest due to their unique properties and widespread potential applications such as dry-cell batteries[12,13],catalysts[14–18],water-purify-ing agents[19]and so on.Many novel synthetic routes have been employed to make micro/nanosized manganese oxides with different sizes,shapes and morphologies[19–26].Among them,a two-step process is often adopted.Solid precursors containing Mn arefirst prepared and then converted to manganese oxide.In particular,MnCO3have been demonstrated to be effective precursors to synthe-size manganese oxide.Zhao et al.synthesized nanoporous c-MnO2via a facile route using a hydro-thermal treatment and sequential thermal decomposition of MnCO3[27].Fei et al.reported a simple controlled preparation of hierarchical hollow microspheres and microcubes of MnO2nano-sheets through self-assembly with a MnCO3crystal-templating process[28].Cao et al.synthesized various Mn2O3hollow structures,such as spheres,cubes,ellipsoids,and dumbbells via a MnCO3 precursor route[29].We also prepared MnO2and Mn2O3hollow dumbbells using MnCO3hollow microstructures as a precursor template[30].However,the number of reports on one-pot synthesis of non-spherical hollow structures of this class of compound intermediates is significantly limited because of the paucity of non-spherical templates and difficulty in forming uniform coatings around high-curvature surfaces.Herein,we developed a facile process for controlled synthesis of MnCO3 hollow cube-like nanostructures using EG as the solvent.The as-obtained MnCO3can be thermal con-verted to phase-pure Mn2O3maintaining their pristine shapes essentially unchanged.The formation mechanism of the hollow structures can be attributed to an inside-out Ostwald ripening process.As an example of potential applications,the as-obtained hollow nanostructures were used as catalyst in CO oxidation and exhibited relatively high activity.2.Experimental2.1.PreparationAll chemicals were of analytical grade and used as received without further purification.In a typical synthesis,MnCl2Á4H2O(1.6g),urea(0.5g),deionized water(H2O,1mL)and poly(vinyl pyrrolidone) (PVP,K-30;0.4g)were added to ethylene glycol(EG,50mL)in a150mL roundflask.Then the mixture was stirred with a magnetic stirrer bar to give a clear solution and heated to refluxing temperature(ca. 190°C)under the ambient pressure.About20min later,a white precipitate began to appear,indicat-ing the formation of MnCO3.The solution was heated for another60min to ensure the formation ofL.Liu et al./Superlattices and Microstructures72(2014)219–229221 the hollow structures before allowed to cool to room temperature.The white product was collected by centrifugation and washed with deionized water and ethanol several times,and then dried in an oven at80°C for12h.In such a reaction,the nanostructures could also be synthesized without using of PVP;however,the quality and the stability of these nanostructures would be greatly improved if PVP was present.Mn2O3hollow nanostructures were obtained by annealing MnCO3in a muffle oven at500°C with a ramping rate of3°C minÀ1.2.2.CharacterizationPhase purity and structure of the samples were examined by XRD using a Bruker D8-Advance pow-der X-ray diffractometer with Cu K a radiation(k=0.15418nm).The morphology and nanostructure of the products were characterized using a transmission electron microscope(TEM,JEM100-CX II)with an accelerating voltage of80kV,and afield-emission scanning electron microscope(FE-SEM,Hitachi, S4800).Thermal gravimetric analyze(TGA)was carried out to determine the composition of products at a heating rate10°C minÀ1from40to600°C under air atmosphere(SDTQ-600,Thermo Elemental). Fourier transform infrared(FTIR)spectra were recorded for samples using KBr pellet technique in the range of400–4000cmÀ1(Bruker VERTEX-70).Surface analysis of samples was carried out with X-ray photoelectron spectroscopy(XPS,Thermo ESCALAB-250)with a standard Al K a source.All binding energies were referenced to the C1s peak(284.6eV)arising from surface hydrocarbons(or adventi-tious hydrocarbons).Measurement of specific surface area and analysis of porosity for the products were performed through measuring N2adsorption–desorption isotherms at77K with a Quanta-chrome NOVA-3000system.2.3.Catalytic experimentsThe catalytic activity of the as-obtained samples was evaluated on a continuousflowfixed-bed micro-reactor operating under atmospheric pressure.In a typical experiment,50mg catalyst particles were placed in the reactor.The reactant gases(1%CO,10%O2and89%N2)passed through the reactor at a rate of100mL/min.The composition of the gas exiting the reactor was analyzed with an online infrared gas analyzer(Gasboard-3020,China Wuhan Cubic Optoelectronics Co.,Ltd.),which simulta-neously detects CO and CO2with a resolution of10ppm.The results were further confirmed with a Shimadzu gas chromatograph(GC-14C).3.Results and discussion3.1.Formation of the MnCO3hollow nanostructuresThe phase purity of the as-prepared MnCO3hollow nanostructures was investigated using XRD,as shown in Fig.1a.All of the reflections of the XRD pattern can be indexed to the pure rhombohedral phase of MnCO3(JCPDS Card No.44-1472),and the absence of other diffraction peaks confirms the generation of phase-pure MnCO3crystals.To explore the formation mechanism of the MnCO3hollow structures,samples collected at differ-ent time intervals from the reaction mixture were investigated by TEM.As shown in Fig.2,four obvi-ous evolution stages could be identified.At an early stage,primary precipitates(amorphous) accompanied with the desired crystal products can be detected(Fig.2a),which could be converted to the MnCO3phase completely when the reaction time was prolonged.As the reaction proceeded, the amount of the microstructures increased at the expense of the nanoparticles.Eventually no tiny nanoparticles remained and the sample was composed entirely of the cube-like microstructures,as shown in Fig.2b.Prolonging the reaction time to30min,hollow core/shell microstructures were formed(Fig.2c).Further prolonging reaction time to60min,the sample consisted of microstructures were completely hollow(Fig.2d).The hollow MnCO3nanostructures are formed with a mean length ofFig.1.XRD spectrum of the MnCO3hollow microstructures.TEM images of the MnCO3samples obtained at different reaction time intervals once the precipitate appeared(a)5,(b)15,(c)40,and(d)60min.1l m.Moreover,the surface of the hollow structure is rough,indicating that the shell of the cubes is built with irregular tiny MnCO3nanoparticles.Based on the above observations,the formation pathway of the hollow MnCO3microstructures can be attributed to the Ostwald ripening process.Here we propose a possible process for the formation of the hollow nanostructures.In an initial stage,primary precipitates were formed instantaneously and quickly grew into the primary particles when supersaturation in the solution phase was reached.This initial solid might be an amorphous or poor crystallized phase owing to rapid spontaneous nucleation. In the following stage,the resultant crystallites were aggregated into cube-like crystals quickly inorder to minimize the overall energy of the system.These aggregated MnCO3solid microstructures were metastable due to their high surface energy.As the reaction proceeded,the reaction rate slowed down due to the depletion of the reactants.As a result,the crystal growth stage transferred to a kinet-ically controlled process.As the reaction proceeded,the inner nanocrystallites,which had a higher surface energy,would dissolve and transferred to these surface sites,where these nanoparticles on the surface acted as new nucleation sites.With further increase in the reaction time,the cores in the center could be completely consumed and thefinal hierarchical hollow structures were fabricated. The hollowing process is essentially similar to what has been researched intensively in the preparation of Sn–TiO2[31],Ni(OH)2[32],and Cu2O[33]hollow nanostructures via a inside-out evacuation mech-anism.Upon ripening,interior spaces can be created in accordance with matter state and agglomer-ative pattern of pristine crystallites.The effect of the H2O amount was also investigated.The carbonate anions in the synthesis were pro-vided by hydrolyzation of urea(Eqs.(1)and(2)),so it was essential to add a certain amount of H2O to the synthetic mixture in order to form MnCO3crystals(Eq.(3)).Note that the addition of H2O in the synthetic solution was essential to control the morphology of the MnCO3crystals.As an example,when H2O was not added to the solution mixture,no product was obtained.With an increase to2mL of H2O, the as-prepared product was solid cube-like microstructures with a length in region of500–600nm and no hollow structures were observed(Fig.3).The smaller size may be the result of more MnCO3 nuclei caused by a higher H2O concentration in the reaction mixture,which promote the formation of smaller clusters.Moreover,MnCO3hollow dumbbells were obtained when the same molality of Mn(NO3)2solution(50wt.%)instead of MnCl2Á4H2O and H2O was used[30].On the basis of the exper-imental results,the formation of these hollow nanostructures can now be further addressed.The anions such as ClÀand NO3Àalso influenced the morphology of the products.We thought that the different anion(ClÀor NO3À)in the reaction mixture might result in different reaction condition and environment of MnCO3nuclei,which kinetically favor the preferential crystal aggregation along different direction.COðNH2Þ2þ3H2O!2NHþ4þCO2þ2OHÀð1Þ2NHþ4þCO2þ2OHÀ!2NHþ4þCO2À3þH2Oð2Þimage of the MnCO3sample obtained using2mL of H2O addedL.Liu et al./Superlattices and Microstructures72(2014)219–2292234.Typical FTIR spectrum of the MnCO3hollow microstructures.Fig.5.Representative XPS spectra of the MnCO3crystals:(a)wide scan,(b)C1s,(c)O1s,and(d)Mn2p. crystals.The bands at round3440and1628cmÀ1are assigned to the stretching vibration of the O–H group of surface absorbed molecular water and hydrogen-bond O–H.The presence of CO32Àin the MnCO3sample is evidenced by itsfingerprint peaks at1449,864,725cmÀ1,according to normal modes of vibration of planar CO3molecules/ions;the peak located at2489cmÀ1is also commonly associated to a vibrational mode of carbonate anion[34].The weak peak at1798cmÀ1is attributed to an overtone or combination band composition of the carbonate groups and divalent metal ions.To have further information on surface composition of the samples,XPS analysis has been per-formed in this work.Fig.5a shows a wide scan spectrum of the as-prepared sample.The peaks locatedL.Liu et al./Superlattices and Microstructures72(2014)219–229225 at284.6,532.1and642.5eV are assigned to the characteristic peaks of C1s,O1s,and Mn2p,respec-tively.As expected,the above sharp peaks confirm the abundant existence of carbon,oxygen,and manganese elements on the sample surfaces of MnCO3.The peaks at289.4eV in the C1s spectrum is assigned to the carbon element in association with oxygen in the carbonate ions.The peaks at 284.6and286.2eV can be attributed generally to surface-adsorbed hydrocarbons and their oxidative forms(e.g.C–OH)[34].The predominant O1s peak at532.1eV belongs to the lattice oxygen of MnCO3. The core level peaks of Mn2p at642.2and654.4eV correspond to Mn2p3/2and Mn2p1/2of MnCO3 [35,36].The Mn2p peaks at644.5and647.8eV(Mn2p3/2)can be assigned to satellite shake-ups of the components of Mn2O3surface phase,respectively.Fig.6.TG and DSC curves for the as-obtained MnCO3hollow cubes.Fig.7.XRD spectrum of the Mn2O3hollow cubes.TEM images of the prepared Mn2O3nanostructures:(a)FE-SEM image of a broken hollow cube;(c)TEM image of a single hollow cube;(d)HRTEM image from the shell of hollow cube;(e)TEML.Liu et al./Superlattices and Microstructures72(2014)219–229227 Fig.8presents the SEM and TEM images of the samples from this oxidative heat-treatment.The pristine morphologies of the MnCO3crystals were well preserved in their oxide products,and no appreciable shape and size changes were observed.However,their surfaces seem to become rougher, suggesting the generation of porous Mn2O3through the calcination.The cube-like Mn2O3hollow microstructure could be further confirmed by FE-SEM image of a broken Mn2O3cube(Fig.8a).The shell thickness is ca.40nm and the shell is comprised of nanoparticles,and the corners(angles included by two surfaces)of the cubes are not strictly right,which is in good agreement with the TEM results(Fig.8b and c).As shown in Fig.8d,lattice plane spacing calculated from the HRTEM images is ca.0.38nm hkl(211).Fig.8e shows the TEM image of the core–shell Mn2O3microstructures through the heat-treatment.To investigate the specific surface areas and the porous nature of the Mn2O3samples,BET gas-sorp-tion measurements were performed.N2adsorption–desorption isotherm of these porous microstruc-tures are shown in Fig.9and the inset illustrate the corresponding Barrett–Joyner–Halenda(BJH)pore size distribution plots.From the pore distribution curve,the Mn2O3samples showed mesoporous structural characteristics and had a monomodal pore size distribution,which is5nm for hollow struc-tures and7nm for core–shell structures,respectively.The specific surface area using the BET method is87.2m2/g for hollow structures and70.4m2/g for core–shell structures,respectively.3.4.Catalytic performanceCO Catalytic oxidation is environmentally important and here is used as a probe reaction to eval-uate the catalytic performance of Mn2O3nanostructures using a continuous-flow,fixed-bed microre-actor.Fig.10displays the temperature dependence of the CO conversions for catalysts with different morphologies.It is clear that the hollow cubes show a much higher conversion at the same temper-ature.For example,at180°C,the CO conversion of hollow structures is80.5%,which is much higher than that of core–shell structures(45.7%).Furthermore,complete CO conversions can be achieved at 210°C and270°C over hollow and core–shell Mn2O3catalyst,respectively.The clear contrast of the catalytic activity between hollow and core–shell Mn2O3powders can be attributed to the difference29.N2physisorption isotherms of the hollow(a)and core–shell(b)Mn2O3microstructures.The inset displays corresponding BJH pore size distribution.4.ConclusionsIn summary,we have developed a polyol process for preparation of hollow and core–shell cube-like MnCO 3nanostructures with the assistance of PVP in EG solution.On the basis of our time-dependent synthetic experiments,the formation of these MnCO 3crystals can be attributed to a nucleation–aggre-gation–ripening process.In air atmosphere,Mn 2O 3hollow microstructures have been obtained from the MnCO 3submicrometer crystals after oxidative thermal decomposition at 500°C with a ramping rate of 3°C min À1.Our surface textural/morphological investigation further reveals that the thermally converted Mn 2O 3products possess mesoporosity and essentially maintain their pristine MnCO 3mor-phologies unaltered.CO catalytic oxidation experiments indicated the Mn 2O 3hollow cubes show bet-ter catalytic performance than core–shell Mn 2O 3cubes,possibly due to its large specific surface area.AcknowledgmentsThis work was supported by the 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Published online 26July 2016 | doi: 10.1007/s40843-016-5046-1Sci China Mater 2016,59(7):567–573Novel synthesis of V 2O 5hollow microspheres for lithium ion batteriesLu Zeng 1,2,Anqiang Pan 2*,Shuquan Liang 2,Jinbin Wang 1*and Guozhong Cao 3ABSTRACT In this work,hollow structured V 2O 5micro-spheres were fabricated from solid vanadium precursor microspheres which were prepared by microwave-assisted,solvothermal approach.In the annealing process,the spher-ical precursor microspheres can be converted into hollow microspheres,serving as a sacrificial template.The synthesis approach is quite different from the previously reported approaches for the preparation of hollow structured V 2O 5microspheres.As cathode materials for lithium ion batter-ies,the hollow-structured V 2O 5microspheres exhibit high capacity and good rate capability.The electrodes deliver specific discharge capacities of 132and 113mA h g −1at the current densities of 1C and 8C,respectively.Keywords: vanadium oxides,solvothermal,microwave-assisted synthesis,hollow microspheres,lithium ion batteriesINTRODUCTIONVanadium pentoxide (V 2O 5)has been extensively studied as a potential cathode material in rechargeable lithium-ion batteries (LIBs),due to its high capacity,abundant re-sources of vanadium elements in storage,and easy fab-rication [1–5].However,the low diffusion coefficient of lithium ions (10−12to 10−13cm 2s −1)[6]and low electronic conductivity (10−2to 10−3S cm −1)[7]impede its elec-trochemical performance.Recently,nanomaterials are effective to improve their electrochemical performance because of the kinetic enhancement for Li +ions diffusion and electron transportation [7–15].To date,various V 2O 5nanostructures,such as nanofibers [16,17],nanowires [18]and hierarchical microspheres [19–22]have been reported with improved electrochemical properties.Among the nanostructured materials,hierarchical nan/omicrostructures are preferred because the self-aggre-gation upon cycling can be inhibited at some extent.Inparticular,hollow structured vanadium oxides are of great interest,due to their structural advantages.First,the hol-low interior can better accommodate the volume change upon cycling.Second,the porous exterior shell allows the easy penetration of the electrolyte.Third,the nanopar-ticles which compose the microsphere can increase the contact area between electrode and electrolyte,which ensures the good rate capability of the electrode materials.To date,the synthesis strategies of hollow V 2O 5micro-spheres can be generally grouped into two classes:the Ostwald-ripening [9,19]and template-assisted fabrication [20].For Ostwald-ripening synthesis,the hollow precur-sors are initially formed during the solvo/hydrothermal process and can be converted into V 2O 5microspheres in the subsequent annealing process in air.For instance,Pan et al .[9]successfully fabricated hollow structured VO 2mi-crospheres with complex interiors and converted them into V 2O 5microspheres with well-preserved structures,which exhibited high capacity and tunable electrochemical prop-erties.Template-assisted synthesis of V 2O 5microsphere is a straightforward approach by first growing vanadium precursor against the templates and removing the tem-plates thereafter.More recently,Wu et al .[20]reported the growth of vanadium precursors by template against carbon microspheres and their conversion into multi-shelled V 2O 5microspheres in the subsequent annealing in air.The pre-pared double-shelled V 2O 5microspheres exhibited high specific discharge capacity and good stability.Cao et al .[23]reported the polyol synthesis of nanorod-assembled hollow microspheres using polyvinyl pyrrolidone (PVP)as a surfactant.The structures of the V 2O 5microspheres were pre-fixed by the precursor microspheres.However,the synthesis of hollow V 2O 5microspheres from solid1School of Materials Science &Engineering,Xiangtan University,Xiangtan 411105,China2School of Materials Science &Engineering,Central South University,Changsha 410083,China 3Department of Materials Science &Engineering,University of Washington,Seattle 98195,USA *Corresponding authors (emails:pananqiang@ (Pan S);jbwang@ (Wang J))567microspheres has been rarely reported.The difficulty may be raised from the synthesis of uniform vanadium organic precursor microspheres,which may create hollow interiors due to their large volume shrinkage upon annealing at high temperature.The microwave-assisted synthesis method as a rapid heating route for the fabrication of nanomaterials attracts increasing interests,which also shows some other advan-tages such as environmental friendliness,low cost and easy mass production in a short bining microwave synthesis with hydrothermal process presents a poten-tially faster,more efficient and selective method for the preparation of nanomaterials.Herein,we report the new preparation of hollow structured V2O5microspheres from the microwave-assisted,solvothermally prepared solid microspheres by a thermal induced annealing,in which the solid microspheres function as sacrificial templates. As cathode materials for lithium ion batteries,the V2O5 hollow microspheres exhibit high capacity and good rate capability.EXPERIMENTAL SECTIONSynthesis of V2O5hollow microspheresAll chemicals were of analytical purity and used as received without further purification.In a typical synthesis,200mg of V2O5,4mL of glycerol were dissolved into20mL of iso-propanol under magnetically stirring for30min to get yel-low slurry,which was then sealed in a Teflon-lined auto-clave and kept at3W,180°C for1h in a microwave reac-tor(MDS-6GSMART,Shanghai).After cooling down nat-urally,the dark brown precipitate was collected by centrifu-gation and washed with ethanol several times before dry-ing in an electrical oven at70°C.The dried solid precursor was annealed in air at400°C for1h to obtain V2O5hol-low microspheres.The temperature ramping rate was0.5°C min−1.Materials characterizationThe crystallographic phases of all the products were in-vestigated by powder X-ray diffraction(XRD,Rigaku D/max2500)with Cu Kα(λ=1.5406Å)radiation.The morphologies of the samples were characterized by field emission scanning electron microscope(FESEM,FEI Nova NanoSEM230),transmission electron microscopy(TEM, JEOL-JEM-2100F)and high resolution transmission electron microscope(HRTEM,TecnaiG2F20).Thermo gravimetric(TG)and differential scanning calorimetry (DSC)analyses were performed on a combined TG and DSC analysis instrument(Netzsch STA449C,Germany).Electrochemical measurementsThe working electrode was prepared by dispersing V2O5, carbon black(Super P-Li)and poly(vinylidene fluoride) (PVDF)binder in N-methylpyrrolidone with a weight ratio of70:20:10to form a slurry,which was coated on an alu-minum foil and dried in a vacuum oven at100°C for20h. The electrode disks were1.2cm in diameter and had an ac-tive material loading of0.6–0.9mg cm−2.Lithium foil was used as the counter and reference electrode,and1.0mol L−1LiPF6in ethyl carbonate/dimethyl carbonate(1:1v/v ratio)was used as the electrolyte.The cyclic voltammetry (CV)measurements were performed on an electrochemi-cal workstation(CHI604E,China)in the voltage range of 2.5–4V vs.Li/Li+under a scan rate of0.1mV s−1.The gal-vanostatic charge/discharge performance of the electrodes was evaluated at room temperature using a Land battery tester(Land CT2001A,China).RESULTS AND DISCUSSIONThe possible formation mechanism of the V2O5hollow spheres is shown in Fig.1.The commercial V2O5powder may experience a dissolution and recrystallization process in the mixed solvents of isopropanol during the solvother-mal process.The V5+from V2O5is partially reduced to V4+ by the organic species and the V2O5particles are converted into V4O9solid microspheres with organic species.In the later annealing process,the organic species in the solid spheres are decomposed,resulting in a volume contraction to create the interior hollow space.At the same time,the vanadium oxide is oxidized into V2O5microspheres. Fig.2a shows the XRD patterns of the solvothermally prepared precursor and its annealing product.Two main broad peaks are detected in the XRD pattern of the solvothermally prepared precursor and the whole pattern is in good agreement of the XRD pattern of V4O9 (JCPDS card23-0720).The broad peaks suggest the low crystallinity or small crystallites of V4O9in the precursor. Moreover,the valence of V5+in V2O5was partially reduced to V4+in the solvothermal process[24,25].After annealing the microsphere precursor in air,orthorhombic V2O5 phase(space group:Pmmn(59),JCPDS card41-1426) can be obtained with high purity.The phase transition from precursor to V2O5crystallites was studied by TG and DSC analysis and the result is shown in Fig.2b.The initial weight loss below279°C can be attributed to the evaporation of physical or chemical bounded water.The detection of a fast weight loss between279and370°C and an exothermal peak at321o C indicate the existence of organic species in the solvothermal prepared precursors.568Figure 1 Schematic illustration of the formation mechanism of the V 2O 5hollow spheres.Figure 2 (a)XRD patterns of the microwave-assisted solvothermally prepared product (black curve)and its annealing product (red curve);(b)TG and DSC results of the solvothermal products from room temperature to 600°C in air.The temperature ramping rate was set to 10°C min −1.As we know,the simple phase changes from V 4O 9to V 2O 5will cause the weight increase during annealing process.However,the large weight loss (about 10%)is related to the large amount of organic species in the vanadium precursor.The slight weight increase above 380°C can be attributed to the oxidation of vanadium species into V 2O 5.According to the TG and DSC analysis result,400°C was selected as the annealing temperature for the calcination process in air.Fig.3shows the structural characterization results of the vanadium precursor and the annealed V 2O 5.Fig.3a shows the SEM image of the solvothermally prepared pre-cursor particles,which are of spherical morphology with a mean diameter of about 1μm.The energy dispersive X-ray spectroscopy (EDS)result (inset of Fig.3b )indi-cates the precursor microspheres are composed of C,V and O.The clear detection of C element in the precursor mi-crospheres suggests the existence of organic species in the precursor microspheres.The result is in good agreement with the TG and DSC results.The TEM image (Fig.3c )reveals the solid interior of the microspheres.The struc-tures of the obtained V 2O 5from the solid vanadium pre-cursor are also characterized.Fig.3d shows the spherical morphology of the obtained V 2O 5with a mean diameter of about 1μm.However,the surface of the microspheres be-comes rough and porous.The surface structural changes can be attributed to the removal of organic species dur-ing the annealing process,which creates the pores on the surface.In general,the spherical morphology is well re-tained.The TEM image of the V 2O 5microspheres (Fig.3e )clearly presents the hollow interiors of the V 2O 5mi-crosphere and the porous feature of the exterior shell.The HRTEM image (Fig.3f )shows the layer fringes of 0.5714nm for V 2O 5hollow microspheres,in good agreement with the planar distance of (200)lattice planes.The selected area electron diffraction (SEAD)pattern (inset of Fig.3f )also confirms the good crystallinity of the obtained V 2O 5hol-low microspheres.It is worth mentioning that the forma-tion of V 2O 5hollow microspheres reported in this work is quite different from the previously reported synthesis strategy [26],such as Ostwald-ripening mechanisms [13]and template-assisted synthesis [20].The formation of the hollow microsphere can be attributed to the volume con-traction of the solid spheres after removing the organic species during the calcination process in air.The removal of organic species creates the porous feature of the exterior shells.In the whole process,the solid microspheres are ro-bust enough and can serve as self-sacrificial templates for the construction of the hollow microspheres.Fig.4a shows the Raman spectra of the V 4O 9solid spheres.The peaks located at 96,140, 191, 282, 403,528,569Figure 3 FESEM images (a and b),the EDS (inset of b)and TEM image (c)of the solvothermally prepared product;FESEM image (d),TEM (e),HRTEM image (f)and the SAED pattern (inset of f)of the calcination product.688and 990cm −1are ascribed to the characteristic peaks of V 4O 9[27,28],which is in good agreement with XRD re-sults.The hierarchical nature of the V 2O 5porous hollow spheres is further evaluated by nitrogen adsorption-des-orption measurement and the results are shown in Fig.4b .The isotherm can be described as type II with a H3hys-teresis loop,which indicates the slit-shaped pores in the V 2O 5porous hollow spheres.The measured Brunauer-Em-mett-Teller (BET)surface area of the sample is about 12.146m 2g −1.Barrett-Joyner-Halenda (BJH)calculations disclose that the pore size distribution is mainly in the range of 1–20nm,which is in good correspondence with the TEM image.The V 2O 5hollow microspheres were assembled into coin cells to evaluate their electrochemical performances,and the results are shown in Fig.5.Fig.5a shows five consec-utive CV cycles for the V 2O 5hollow microspheres.During the cathodic scan,two peaks at 3.3and 3.1V vs .Li/Li +cor-respond to the phase transition from α-V 2O 5to ε-Li 0.5V 2O 5,and then to δ-LiV 2O 5,respectively [29,30].During the an-odic scan,the peaks at 3.26and 3.48V are attributed to the Li +de-intercalation process,corresponding to the phase changes from δ-LiV 2O 5,to ε-Li 0.5V 2O 5and then to α-V 2O 5,in reverse [31–33].The large overlap of the CV curves in-dicates the good reversibility of the V 2O 5hollow micro-spheres.Fig.5b shows the discharge/charge profiles of the V 2O 5hollow microspheres at different C-rates.The multi-ple discharge/charge plateaus at different rates indicate the multi-step Li +ions intercalation/de-intercalation process,in good agreement with the CV result.Even at 4C,the plateaus can be still clearly detected.Fig.5c shows the rate performance of the hollow structured V 2O 5electrodes.A specific discharge capacity of 136mA h g −1can be delivered at 1C,which is quite close to the theoretical capacity of 147mA h g −1for one Li +ion intercalation per formula.The electrodes deliver the capacities of 133.0,129.4and 113.8mA h g −1at 2C,4C and 8C,respectively.Even at 16C,the electrode can release a capacity of 86.8mA h g −1.The re-sults demonstrate the good rate capability of the electrodes.Fig.5d shows the cycling performance ofthe hollow struc-Figure 4 (a)Raman spectra of the V 4O 9solid spheres;(b)nitrogen adsorption-desorption isotherm of the V 2O 5porous hollow spheres,and the pore size distribution of the V 2O 5porous hollow spheres (inset of b).570Figure5 (a)CV curves of the V2O5microspheres at a scan rate of0.1mV s−1;(b)discharge/charge profiles and;(c)rate performance of the V2O5 microspheres at various rates in the voltage range between2.5–4.0V vs.Li/Li+;(d)long-term cycling performance of the V2O5microspheres in the voltage range of2.5–4.0V at5C and10C.Here1C=147mA g−1.tured V2O5microspheres at the rates of5C and10C.The electrodes exhibit an initial discharge specific capacity of 130mA h g−1at5C and retain the capacity of111.8mA h g−1after500cycles,with an average capacity fading rate of0.3%per cycle.The electrodes also show good capacity retention at10C.The capacity fading rate is0.5%per cy-cle.Moreover,the Coulombic efficiency of the electrode is very close to100%.All the electrochemical results indicate the good electrochemical performance of the V2O5hollow microspheres,which can be attributed to their structural advantages:(1)the hollow interiors can better accommo-date the volume change upon cycling;(2)the porous ex-terior shell allow the easy penetration of the electrolyte;(3) the large surface area can increase the contact area between electrode and electrolyte,which ensures the good rate ca-pability of the electrode materials. 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11:1990–199833Qin M,Liang Q,Pan A,et al.Template-free synthesis of vanadium oxides nanobelt arrays as high-rate cathode materials for lithium ion batteries.J Power Sources,2014,268:700–705 Acknowledgments This work was supported by the National Natural Science Foundation of China(51302323),the Program for New Century Excellent Talents in University(NCET-13-0594),and the Natural Science Foundation of Hunan Province(14JJ3018).Author contributions Zeng L carried out the main experiment and wrote the paper;Pan A and Wang J made the research plan and revised the manuscript.Liang S and Cao G participated the data discussion. 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UHMW一PAN中空纤维膜的研制及应用（4）-----UHMW-PAN中空纤维膜的制备工艺沈新元1 ,朱新远2 ,王庆瑞11东华大学材料科学与工程学院、纤维材料改性国家重点实验室，上海(20005)2上海交通大学应用化学系，上海 (200031）摘要：以超高相对分子质量聚丙烯腈(UHMW-PAN)为原料制备中空纤维膜，研究了纺丝方法和工艺条件对中空纤维膜力学性能的影响。

实验表明，凝胶纺丝制备的中空纤维膜的韧性最好，其合适的工艺参数为：聚合物分子量 Mv=1.29×106，纺丝溶液浓度 C=3%，气隙长度 L=3cm，拉伸倍数 R=14。

关键词：超高相对分子质量聚丙烯腈凝胶纺丝中空纤维膜韧性中空纤维膜作为分离膜的主要形式之一，因为具有装填密度高、比表面积大、组件结构简单等优点，自问世后发展很快，并且已在血液透析、水或其它流体的净化、食品或饮料的生产等领域得到越来越多的应用[1，2]。

但同时也给世界膜技术工作者带来了一个问题，即如何进一步提高中空纤维膜的机械强度，以便它们能经受多次反冲洗而重复使用，以降低操作费用和减少废物。

这方面，日本东丽株式会社等已取得了较大的进展，他们采用重均相对分子质量（Mw）为20万的聚丙烯腈（PAN）作为膜材料，制成了机械强度较高的PAN中空纤维膜，并且已成功地应用于水的除浊[3，4]．有人还将这种中空纤维膜进行碳化，制成了一种新型的无机膜--PAN基中空纤维碳膜，可望在高温气体分离等领域发挥重要作用[5]。

作者合成了黏均相对分子质量（Mv）≥80万的超高相对分子质量聚丙烯腈（UHMW-PAN）[6」，并通过将以其制成的中空纤维膜进行氧化和水解，制成了pH响应性多孔中空凝胶纤维[7]。

本文作为这一研究工作中的一部分，在以前研究[6，8－10]的基础上，以自己合成的UHMW-PAN 为原料纺制中空纤维膜。

制备中空纤维膜可以采用湿法纺丝、干法纺丝、干-湿法纺丝和熔体纺丝[11]。

纳米簇羟基磷灰石中空微球纳米簇羟基磷灰石（nanocluster hydroxyapatite）是一种具有广泛应用前景的新型材料。

它具有独特的结构和优异的性能，被广泛应用于医疗领域、材料科学和生物学等领域。

本文将重点介绍纳米簇羟基磷灰石中空微球的制备方法、结构特点和应用前景。

纳米簇羟基磷灰石中空微球的制备方法多样。

一种常用的方法是溶剂挥发法。

通过在有机溶剂中溶解适量的羟基磷灰石前驱体，并添加表面活性剂和模板剂，形成乳液。

随后，通过挥发有机溶剂，形成中空微球。

这种方法制备的纳米簇羟基磷灰石中空微球具有较小的粒径和较大的比表面积，具有优异的生物相容性和生物活性。

纳米簇羟基磷灰石中空微球具有独特的结构特点。

它们呈球形结构，表面光滑，内部空腔呈中空结构。

在纳米尺度下，它们的表面具有丰富的羟基磷灰石簇，这些簇之间通过强烈的静电作用力相互连接，形成稳定的纳米簇结构。

这种结构使纳米簇羟基磷灰石中空微球具有良好的生物相容性和生物活性，能够有效促进骨组织再生和修复。

纳米簇羟基磷灰石中空微球在医疗领域具有广泛的应用前景。

首先，它们可以作为骨修复材料，用于治疗骨折、骨缺损和骨疾病。

由于纳米簇羟基磷灰石中空微球具有类似于骨组织的化学成分和结构，能够与骨组织紧密结合，促进骨组织再生和修复。

其次，纳米簇羟基磷灰石中空微球还可以用于药物递送系统。

通过将药物包裹在中空微球中，可以实现药物的缓释和靶向释放，提高药物的疗效和减少副作用。

纳米簇羟基磷灰石中空微球还在材料科学和生物学领域具有广泛的应用前景。

它们可以用于制备功能性纳米材料和纳米器件，例如纳米传感器和纳米电池。

由于纳米簇羟基磷灰石中空微球具有较大的比表面积和丰富的表面官能团，能够有效吸附和催化反应物质，具有很高的催化活性和选择性。

纳米簇羟基磷灰石中空微球具有重要的科学研究价值和广阔的应用前景。

通过合理的制备方法，可以获得具有优异性能和多功能的纳米簇羟基磷灰石中空微球。

这些中空微球在医疗领域、材料科学和生物学等领域具有重要的应用价值，将为人类健康和科学研究带来新的突破和进展。

第50卷第12期 辽 宁 化 工 Vol.50，No. 12 2021年12月 Liaoning Chemical Industry December，2021基金项目： 四川省水产局水产养殖业污染物产量调查（项目编号：80303-AHW013）。

收稿日期： 2021-09-27 作者简介： 李漂洋（1996-），女，四川省成都市人，在读硕士，2022年毕业于成都理工大学化学专业，研究方向：超交联有机聚合物吸附环境中污染物。

通信作者： 胡晓荣（1965-），女，教授，博士，研究方向：环境分析化学方向。

超交联有机聚合物的合成及其吸附性能应用进展李漂洋，饶丹梅，胡晓荣（成都理工大学材料与化学化工学院， 四川 成都 610059）摘 要： 基于傅克烷基化反应合成的超交联有机聚合物因其具有孔径大小易调控、比表面积大、物理化学性质稳定等优点，因而被广泛用于吸附各种物质。

综述了超交联有机聚合物的三种常用合成方法，并总结了超交联有机多孔材料对二氧化碳、水中有机污染物、重金属离子以及复杂基体中污染物的吸附性能最新研究进展。

关 键 词：超交联；有机聚合物；多孔材料；吸附性能中图分类号：TQ424 文献标识码： A 文章编号： 1004-0935（2021）12-1830-03多孔材料经历了从无机多孔材料，如沸石分子筛和活性炭；到有机-无机杂化多孔材料，如金属有机骨架化合物（MOFs ）[1]；有机多孔材料，如多孔有机聚合物（POPs ）的演变。

其中POPs 是通过共价键连接而成的聚合物网络，具有较高的比表面积与孔隙率[2]，按其合成方法和结构特点可分为：自具微孔聚合物（PIMs ）[3]，超交联聚合物 ( HCPs)[4]，共价有机网络 (COFs)[5]等。

其中超交联聚合物HCPs 是一类基于傅克烷基化反应制备的新型有机多孔材料，其高度交联的特性使HCPs 的孔径不易坍塌，且具有较高热稳定性。

同时，由于超交联反应选择的芳香单体空间体积小，单体间交联后能显出较多的微孔结构，因而具有巨大的比表面积，具有良好的吸附性能[6]。