Photocatalytic activity of mesoporous microbricks of ZnO nanoparticles prepared by the the
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第29卷第2期 硅 酸 盐 通 报Vo.l 29 N o .22010年4月 B U LLET I N OF THE CH I N ESE CERAM IC SOC I ETYA pr i,l 2010直接沉淀法制备纳米氧化锌晶体及其光催化降解性能研究郭志峰,田 硕,王凌勇,张丽霞,宋彩瑜(河北大学化学与环境科学学院教育部药物化学与分子诊断实验室,保定 071002)摘要:以乙酸锌(Zn(CH 3COO )2)和草酸(H 2C 2O 4)为原料,采用直接沉淀法,分别在水相和有机相中,制备出两份纳米氧化锌。
以它们作为光催化剂,考察了酸性红G 水溶液在可见光下的褪色实验和N,N 二甲基乙酰胺(DMA C)水溶液紫外光催化降解实验。
实验结果表明:(1)直接沉淀法制备的两份样品,经X 衍射和扫描电镜分析是纳米氧化锌;以它们作为光催化剂,都能使酸性红G,在可见光下褪色,褪色速率与Zn O 纳米粒度有关。
(2)加入纳米氧化锌能够提高DMA C 水溶液的紫外降解速率;降解过程中发生了去甲基化反应,产物是N,N 二甲基甲酰胺。
关键词:氧化锌晶体;酸性红;紫外光降解;N,N 二甲基乙酰胺中图分类号:O 78文献标识码:A文章编号:1001 1625(2010)02 0329 05Preparati on of N ano Zn O Crystallizati on by the D irect Preci p itationand Its Characteristic PhotodegradationGUO Zhi feng,TI AN Shuo ,WANG L ing yong,Z HANG L i x ia,SONG Cai yu(Key Laboratory ofM ed i cal Che m istry and M olecu l ar D i agnosis ,M inistry of E du cati on ;C ollege of Ch e m istry and E nvironm ental S ci ence ,H ebeiUn i versity ,Baod i ng 071002,Ch i na)Abst ract :N ano zi n c ox i d e crystallisati o n w as prepared usi n g zinc acetate and oxalic ac i d as ra w m aterials by the d irect precipitation .To study of the capability of photocata l y tic deg radati o n of zi n c ox idecrysta llisation obta i n ed in aqueous and organic so lvents ,the deg rada ti o n o f azorub i n e G w as carr i e d ou t under t h e sunlight in cond ition o f u ltrav i o let light avo i d ance .In add iti o n,w e a lso researched the ro le o f zi n c ox ide cr ystallisations as a photo catalyst i n degradation of the N,N m ethy l aceta m i d e solution under u ltrav io l e t ligh.t The resu lt sho w ed tha:t (1)the t w o piece of sa mp le are nano zi n c ox i d e crysta llisations by X difference and SE M;As a photo cata l y s,t it can have azorubine G so lution faded under v isi b le ligh t and the fad i n g rate depends on the size of the zi n c ox i d e prepared .(2)It can i m prove t h e deg radati o n rate ofN,N m ethy l aceta m i d e to add the zi n c ox i d e and it happened the de m ethy l reacti o n then N,N di m etyl w ere produced .K ey w ords :zinc ox i d e crysta lli s ati o n ;azorubine ;ultrav i o let photodegradation ;N,N di m ethylaceta m i d e作者简介:郭志峰(1955 ),男,研究员.主要从事材料分析研究.E m ai:l gzfvg @ .cn1 引 言光催化降解是一种以半导体金属氧化物作催化剂,利用光能的降解技术。
宫璐等:c12A7.O。
纳米材料的制备及抗茵活性个笼中自由移动,称为自由氧离子,C12A7晶体中笼的负离子浓度为2.1×1021cm一.在氧气气氛条件下制备得到的C12A7具有存储离子O一的能力,这种含有大量氧负离子(O一)的C12A7被称为C12A7.O一氧负离子储存材料【3’6],在材料内部的笼中发生的离子一分子电荷交换反应形成氧负离子:02一+02一O一+O;(2)EPR方法可以测量样品内部具有孤电子物种(如O一和Of等离子)的信号,并且可以得到不同离子的浓度.图2给出采用溶胶一凝胶法在1150℃的氧气气氛中焙烧6h所得样品的EPR图谱.由图2可见,EPR谱图可以由2种氧负离子的信号叠加得到,即O一(乳=g。
=2.043,g。
=1.997)和Of(g。
=2.001,g。
=2.010,&=2.070),这些谱峰的位置均与用固相粉末法合成的样品的标识结果一致口’2川.为了将叠加在一起的信号分开,采用下式拟合了不同离子的谱图口¨:1,2口一,(日)=言【【以耳一日,△日)sin口dp如(3)其中,珥=警(薪lsin2佻。
s2妒+g乞sin2口sin2妒+g毛c。
s2口)。
1/2八Hf—H,胡、)△尼/2仃式中,,(日)为磁场日处的信号强度,口和9是极化角,/是拟合时采用的线型(洛伦兹线型),△Ⅳ是峰间距,乳(江l,2,3)为离子在3个轴上的g值,Ill为普朗克常数,%为测量时的微波频率,卢为玻尔磁子.以CuSO。
・5H:O作为绝对浓度参照标准,通过上述拟合计算出制备的C12A7.O一材料中的O一和Of离子的浓度.结果表明,材料中所含的O一和0f离子的浓度与焙烧温度和焙烧时间相关.于900℃焙烧6h制备的C12A7.O一材料中O一和Of离子的浓度仅有约1017cm。
3量级,1150℃焙烧4h制备的材料中所含O一和Of离子浓度只有约1×10埽cm~,而1150℃焙烧6h时O一和Of离子浓(4)(5)310320330Magne6c6eldintcnsity,mT№.2期’icaIEPRp舭眦打咖the鲫pIesinteredino珂窖蛐砒11鼬℃f打6h口.FittiIlg;6.calcIlltated0一;c.ca】hha士耐Of;d.蛳删red.度大幅度提高到了1.2×10加cm一,进一步提高焙烧温度和延长焙烧时间没有发现O一和Of离子浓度有明显增加.采用固相粉末合成法制备c12A7一O一材料时,需要在1350℃下煅烧16h才能使材料中的O一和Of离子浓度达到10加cm。
高温热解ZIF-8制备系列Ce-ZnO 及其光催化性能研究吴梦瑶,吴佳琳,王卉,吴圣姬(杭州电子科技大学材料与环境工程学院,浙江杭州310018)[摘要]以2-甲基咪唑、醋酸锌与硝酸铈为原料,在常温下制备了系列掺入Ce 的ZIF-8金属有机框架材料,然后通过高温焙烧制得表面有缺陷的Ce-ZnO 微纳米材料。
利用XRD 、TG 、SEM 等对制备的Ce-ZnO 进行了表征,并以高压汞灯为光源,以有机染料罗丹明B 为目标污染物,考察了Ce-ZnO 的光催化活性。
结果表明,相比于ZIF-8高温热解制得的ZnO ,Ce-ZnO 具有更好的光催化活性和稳定性,当Ce 掺杂量为1.0%时,其性能最佳。
[关键词]ZIF-8;水处理;Ce 掺杂ZnO ;光催化[中图分类号]X703[文献标识码]A[文章编号]1005-829X (2019)10-0063-04Preparation of Ce-ZnO catalysts by high ⁃temperature pyrolysisof ZIF-8and analysis on the photocatalytic propertiesWu Mengyao ,Wu Jialin ,Wang Hui ,Wu Shengji(College of Materials and Environmental Engineering ,Hangzhou Dianzi University ,Hangzhou 310018,China )Abstract :A series of Ce ⁃doped ZIF-8metal-organic framework materials were prepared from 2-methylimidazole ,zinc acetate ,and cerium (Ⅲ)nitrate at normal temperature ,and then were roasted under high ⁃temperature to obtain the surface defected Ce-ZnO micro ⁃nanometer materials.The Ce-ZnO catalysts were characterized by XRD ,TG ,SEMand EDS.High pressure mercury lamp as light source ,the photocatalytic activities of Ce-ZnO catalysts were investi ⁃gated by the degradation of the soluble organic dye rhodamine pared with ZnO catalyst prepared by high ⁃tem ⁃perature pyrolysis of ZIF-8,Ce-ZnO catalyst had better photocatalytic activity and stability.Moreover ,the best per ⁃formance of Ce-ZnO catalyst was found at the Ce doping amount of 1.0%.Key words :ZIF-8;water treatment ;Ce ⁃doped ZnO ;photo ⁃catalysis 据统计〔1〕,我国染料年产能约为130万t ,占全球产能的60%以上,居世界首位。
无机材料的乙醇溶剂热合成及应用无机材料的乙醇溶剂热合成及应用SOOCHOW UNIVERSITY博士学位论文论文题目无机材料的乙醇溶剂热合成及应用研究生姓名廉锁原指导教师姓名康振辉专业名称无机化学研究方向无机材料化学论文提交日期 2013 年 3 月无机材料的乙醇溶剂热合成及应用中文摘要中文摘要本论文探索了用乙醇作为溶剂, 通过低温溶剂热合成一些无机材料 ,包括过渡金属氧化物、碳微球材料、金属氧化物/ 碳复合材料等。
乙醇是除水外最便宜的溶剂 , 所以在合成化学 , 特别是溶剂热合成上被广泛的用作溶剂 ,但是在本论文中除作溶剂外, 还可以在碘的催化下低温碳化, 作为碳源。
在本论文中所用的反应容器是普通的内衬聚四氟乙烯的不锈钢反应釜 , 这种反应釜在使用时一般不超过 200 ?。
所以在本论文中的合成都是属于中低温溶剂热合成。
溶剂热具有简单、反应物与温度都易调控的特点。
合成的无机材料主要有以下表征手段 : 扫描电子显微镜 (SEM ) 、能谱 (EDS ) 、透射电子显微镜 (TEM)、X 射线粉末衍射(XRD)、氮气吸附脱附 (BET ) 、红外 (IR ) 、紫外-可见 (UV-Vis ) 、拉曼(Raman)、X 射线光电子能谱 (XPS ) 及电化学工作站等。
最后根据所合成的无机材料的各自性质的不同分别对其应用做了初步研究。
具体工作包括以下几部分:1、以乙醇为溶剂, 以 FeCl ? 6H O 为溶质, 高温下令其醇解可以得到形态不同3 2氧化铁材料, 包括核-壳有分层结构的α-Fe O 。
具体研究了时间、浓度、2 3温度等条件对所合成的α-Fe O 材料形态和结构的影响。
通过对反应时间2 3的研究给出了可能的形成机理。
以核-壳结构的α-Fe O 为催化剂,研究2 3了苯甲醇氧化制备苯甲醛的催化反应, 研究发现以此氧化铁为催化剂同时 3+ 可以提高反应的选择性和转化率。
若以 Fe 为催化剂时转化率高, 但是选择性很低,主要生成苯甲酸,若以商业α-Fe O 或 Fe O 为催化剂,则转 2 3 3 4 化率很低。
Vol.53 No.1Jan.,2021第 53 卷 第 1 期2021年1月无机盐工业INORGANIC CHEMICALS INDUSTRYDoi:10.11962/1006-4990.2020-0064]开放科学(资源服务)标志识码(OSID)片状铋/钒酸铋复合催化剂的制备及其光催化性能冯 飞「,李书文1,汪铁林1,2,王为国匕王存文1'2(1.武汉工程大学化工与制药学院,湖北武汉430205 ; 2.武汉工程大学绿色化工过程教育部重点实验室)摘要:用溶剂热法合成了一系列不同铋含量的片状铋/钒酸铋(Bi/BiVO 4)复合光催化剂。
采用X 射线衍射 (XRD)、X 射线光电子能谱(XPS)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、紫夕卜-可见漫反射光谱(UV-vis DRS)、电感耦合等离子发射光谱(ICP-OES)、氮气吸附脱附和光电流响应等技术对所制备的催化剂进行了表征。
通过氙灯下光催化降解亚甲基蓝的性能来评价样品的光催化活性,实验结果表明铋的自掺杂能显著提高钒酸铋的光催化活性。
最后,通过自由基捕获实验对铋/钒酸铋光催化机理进行了探讨。
关键词:钒酸铋;复合半导体;光催化;染料降解中图分类号:0643.36 文献标识码:A 文章编号:1006-4990(2021)01-0107-06Synthesis and photocatalytic performance of sheet -like Bi/BiVO 4 composite catalystFeng Fei 1, Li Shuwen 1, Wang Tielin 1,2, Wang Weiguo 1,2, Wang Cunwen 1,2(1.School of Chemical Engineering and Pharmacy , Wuhan Institute of Technology , Wuhan 430205,China ;2.Key Laboratory of Green Chemical Engine e ring Proces s of M inistry ofEducation , Wuhan Institute of Technology )Abstract : A series of sheet-like Bi/BiVO 4 composite photocatalysts with different Bi contents were synthesized using solvo thermal method.The prepared catalysts were characterized by using X-ray diffraction (XRD ), X-ray photoelectron spectro-scopy ( XPS ), scanning electron microscopy (SEM ), transmission electron microscopy ( TEM ), ultraviolet-visible diffuse reflec tion spectroscopy (UV -Vis DRS ), inductively coupled plasma optical emission spectroscopy (ICP-OES ), nitrogen adsorp tion-desorption analysis and photocurrent response measurements.The photocatalytic performance of the sample was assessed by photodecomposition of methylene blue (MB ) under xenon lamp irradiation.The results showed that the photocatalytic ac tivity of BiVO 4 was enhanced significantly with Bi self-doping.Finally , the photocatalytic reaction mechanism of Bi/BiVO 4composite was discussed by free radical capture experiments.Key words : bismuth vanadate 曰 composite semiconductor ; photocatalysis 曰 dye degradation单斜相钒酸铋(BiV04)具有价廉、无毒等优点咱1],是一种优良的光催化材料。
Bi2O3-ZnO复合材料的制备及其性能陈庆国;顾菲菲;程雪芬;晋晓峰【摘要】以Bi2O3纳米棒为前驱体,通过溶剂热法合成了一维Bi2O3-ZnO复合材料光催化剂.XRD物相分析,复合材料光催化剂为六方纤锌矿结构的ZnO和四角形结构的Bi2O3;SEM 形貌观察,复合材料光催化剂为棒状Bi2O3,平均直径为(450±50) nm,长度为(5±1)μm,以及少量的ZnO纳米粒/片生长在Bi2O3的表面.在可见光照射下,分别以纯的Bi2O3、ZnO 和Bi2O3-ZnO为光催化剂,通过降解染料亚甲基蓝(MB)和苯酚进行光催化性能研究.%One-dimensional Bi2O3-ZnO composite materials have been successfully synthesized by solvothermal method using Bi2O3 nanorods as precursors.XRD pattern shows that the as-prepared composite was hexagonal ZnO with wurtzite structure andBi2O3 with quadrangle structure.SEM image indicates that the ZnO as-prepared composite was consisted of rod-like Bi2O3 and some ZnO nanoparticles/nanosheets grown on the surface of Bi2O3.The rod-likeBi2O3photocatalyst has (450±50) nm average diameter and (5±1) μm ing pure Bi2O3, ZnO and Bi2O3-ZnO as photocatalyst individually, the property of photocatalyst under UV-Vis was researched by degradation methylene blue (MB) and phenol.【期刊名称】《功能材料》【年(卷),期】2017(048)008【总页数】5页(P155-159)【关键词】Bi2O3-ZnO;复合材料;可见光;光催化活性;降解【作者】陈庆国;顾菲菲;程雪芬;晋晓峰【作者单位】国家铜铅锌及制品质量监督检验中心,安徽铜陵 244000;国家印制电路板质量监督检验中心(安徽),安徽铜陵 244000;国家铜铅锌及制品质量监督检验中心,安徽铜陵 244000;国家印制电路板质量监督检验中心(安徽),安徽铜陵244000;国家铜铅锌及制品质量监督检验中心,安徽铜陵 244000;国家印制电路板质量监督检验中心(安徽),安徽铜陵 244000;国家铜铅锌及制品质量监督检验中心,安徽铜陵 244000;国家印制电路板质量监督检验中心(安徽),安徽铜陵 244000【正文语种】中文【中图分类】TQ050.4Bi2O3是一种带隙能为2.8 eV的重要间隙半导体金属氧化物,它被广泛应用于可见光催化剂材料[1]。
Chinese Journal ofCatalysis 36[2o15)742—749 催化学报2015年第36卷第5期1 wn,w.chxb.cn ava.1 abIe at www.s ciencedi re ct.com ScienceDiIreCt jou rnaI homepage:www.eIsevie r.com/Io cate/ch rlj c Article Photocatalytic activity of mesoporous microbricks of ZnO nanoparticles Drepared bV tIIe tIiermal decomD0Sltlon Ot 一■ ’ 1 1 一・ 一’ 1 ■ ■・■ bis(2-aminonicotinato)zinc(II)
Keyvan Bijanzad aj Azadeh Tadjarodi a。Omid Akhavan b,c, ResearchLaboratoryofInorganicMaterialsSynthesis,DepartmentofChemistry,lranUniversityofScienceandTechnology,Narma ̄Tehran 16846—13114,Iran b DepartmentofPhysics,SharifUniversi ofTechnology,P.O.Box 11155—9161.Tehran,Iran Institute厂0rNanoscienceandNanotechnology,SharVUniversityofTechnology, D Box14588-8969 ̄Tehran,Iran
A R T I C L E I N F 0 Article history: Received 12 December 2014 Accepted 22 January 2015 Published 20 May 2015 Keywords: Znic oxide Bis(2-aminonicotinato]zinc(1I) Mesoporous Photocatalyst Nanoparticle 1.Introduction A B S T R A C T Hollow microblocks of[Zn(anic)2],as a novel coordination compound,were synthesized using 2一aminonicotinic acid(Hanic)and zinc fII1 nitrate tetrahydrate.The chemical composition of the zinc complex,ZnCl2H10N404,was determined by Fourier transform infrared(FTIR)spectroscopy and elemental analysis.The synthesized zinc complex was used as a precursor to produce ZnO nanostructures by calcination at 550。C for 4 h.M0rph0lo gjcal studies by scanning electron micros— copy and transmission electron microscopy revealed the formation of porous microbricks of ZnO nanoparticles.N2 adsorption.desorption analysis showed that the obtained ZnO microbricks pos. sess a mesoporous structure with a surface area of8.13 m /卫and a pore size of22.6 nm.The X.ray djffraction pattern of the final product proved the formation of a pure Zn0 composition with a hex. agonal structure.Moreover,FTIR analyses showed that the 2-aminonicotinic acid ligand peaks were absent after the calcination step.Difluse reflectance spectroscopy was used to determine the band gap energy of the produced ZnO and it was about 3.19 ev.To investigate the photocatalytic activity 0f the porous ZnO nanos七ructure,a series of photocatalytic tests were carried out to remove Congo red,as a representative toxic azo dye.from aqueous solution.The results show that the product can be used as an efficient photocatalyst for waste water treatment with high degradation emciency. @2015,Dalian Institute of Chemical Physics.Chinese Academy of Sciences. Published by Elsevier B.V.A1l rights reserved.
Recently,considerable attention has been given to the syn。 thesis of diverse zinc oxide nanostructures because of their broad range of applications in science and technology such as in rubbers[1】,antibacterial nanomaterials[2,3】,LEDs[4】, transparent transistors【5】,solar cells[6】,photocatalytic re— ductants[7],memory devices[8】,graphene semiconductors [9],organic reactions catalysts[10,11]and photocatalysts [12—14].ZnO is a wide band gap(ca.3.37 eV)n—type semicon— ductor with a hexagonal wurtzite structure.The production of porous Zn0 with a high specific surface area will add to its many advantages.In the mesoporous structure of a semicon— ductor.the channels can act as a light.transfer path for the in— troduction of incident photons onto the inner surface of the photocatalyst and this enhances its activity【151.Additionally, the degradation efficiency of a porous photocatalyst might be enhanced by its adsorption ability because of an jncrease in the probability of a surface reaction with pollutant molecules『161. Additionally,the morphology of nanomaterials also has a great
c0rresponding author.Tel/Fax:+98-21-66022711;E—mail:oakhavan@sharif.edu DOh 10.1016/S1872—2067(14)60305-3 I http://www.sciencedirect.com/science/journal/18722067 I Chin.J.Cata1.,Vo1.36,No.5,May 2015
, , 、、 ● KeyvanB ̄anzadeta1./ChineseJournalofCatalysis36(2015)742—749 impact on their properties and hence their applications[17]. Contrary to expectations,a large shrinkage of the porous mate— rials obtained from the template--directed method occurs dur-- ing heat treatment.This phenomenon causes the collapse of mesoporous structures『18].Therefore,new methods are Fe— quired for the preservation of the mesoporous framework of materials and for a repeatable route to fabricate mesoporous structures. A suitable method for the fabrication of metal oxide nanostructures is the thermal decomposition of metal corn— plexes.To date,difierent architectures of 2一aminonicotinic acid (Hanic]coordination compounds have been synthesized as a consequence of its specific topology_【Tb(anic)3]・0.5Hanic’7H20 with photoluminescence properties 【19], [Ag2- 一O,O (anic)2(NO3)2]n with high antibacterial activity【20】 and【TlMe2(anic)]“21】are examples of coordination com— pounds that contain 2-aminonicotinic acid.To the best of our knowledge,coordination compounds between zinc and 2-aminonicotinic acid have not been reported. It has been reported that ZnO nanoparticles could be gener— ated from solvothermally prepared zinc(11)coordination pol— ymers containing aromatic dicarboxylic acids[22].A zinc ter・ ephthalate metal・organic framework has been reported to give porous cubic—shaped ZnO particles via pyrolytic conversion [23].The mechanochemical process,as a green solid state syn— thetic method,was used to prepare Zn(C204)・2H20,which was then calcined to give ZnO porous nanostructures【241.Zinc hydroxide carbonate was obtained with the assistance of gly. cine and polyvinyl pyrrolidone to produce a nest—like 3D ZnO nanoporous material using post heat treatment[25].Further— more.ZnO nanostructures were synthesized by pulsed laser deposition[26]and radio frequency magnetron sputtering 【27]. Congo red(CR)is one of the most popular secondary diazo dyes and it may cause cancer in humans because of its toxic metabolite benzidine.Its highly colored effluents have low bio— logical oxygen demand and high chemical oxygen demand and they also contain high quantities of dissolved solids【28].In this research,[Zn(anic)2】was synthesized by chemical precipitation and used as a precursor to prepare ZnO nanoparticles after heat treatment.We investigated its photocatalytic activity to— ward the ph0tOdegrada七i0n 0f C Rl 2.Experimental 2.1.Chemicals andsynthesis All the reagents were purchased from the Merck Company in Germany and used without further purification.Congo red (sodium 3,3’一([1,1’一bipheny1]一4,4 diy1)bis(4一aminonaphtha・ lene一1一sulfonate)was used as a model azo dye.Deionized wa一 z圳:… /COOH KOH(aq)heat/stir jIl EtOH/H,o 743 ter was used to prepare all the solutions.For the synthesis,a 3 mmol ethanolic solution of 2一aminonicotinic acid(30 mL)and 3 mmol KOH aqueous solution were mixed until the pH of the solution was 7.as measured by a Metrohm pH meter.1.5 mmol Zn(NO3)2・4H20 aqueous solution(20 mL)was then added dropwise to this mixture while stirring for 20 rain.The result— ant white precipitate of the zinc coordination compound(with a decomposition temperature>350。C1 was filtered.washed and dried at room temperature overnight.Ultimately,it was calcined at 550。C for 4 h to give the ZnO nanostructures.A schematic reDresentation of the reaction is shown in Scheme 1. Commercially available particulate Zn0(particle size:200 nm) and TiOz powder(anatase,particle size:30 rim)were also in— vestigated to compare their photocatalytic activity with that of the synthesized Zn0 nanoparticles.