Thermal-heating CVD synthesis of BN nanotubes from trimethyl borate and nitrogen gas

收稿日期：２００７－１２－２４。

收修改稿日期：２００８－０３－１１。

国家９７３计划（Ｎｏ．２００５ＣＢ６２３６０１）和国家自然科学基金（Ｎｏ．２０４３１０２０）资助项目。

＊通讯联系人。

Ｅ－ｍａｉｌ：ｙｔｑｉａｎ＠ｕｓｔｃ．ｅｄｕ．ｃｎ第一作者：朱永春，女，３０岁，博士后；研究方向：无机纳米材料的合成及性能研究。

"""#"$%%%$"$综述溶剂热法合成碳纳米材料朱永春钱逸泰＊（合肥微尺度物质科学国家实验室，中国科学技术大学化学系，合肥２３００２６）摘要：本文综述了溶剂热法合成多种碳纳米管、纳米电缆、纳米棒、纳米球和纳米空心锥的研究现状。

３５０℃下用金属钾还原六氯代苯，在用不同催化剂时，可分别得到碳纳米管和碳球，碳球的形成可以解释为石墨层的微条卷曲而成。

６００℃下金属镁还原乙醇得到了竹节状和Ｙ－型碳纳米管。

５００℃下还原四氯化碳和碳酸钠可得到平均直径为１００ｎｍ的碳纳米管。

７００℃下金属锌还原乙醚制成了左右螺旋型交织的碳纳米管。

在硫的存在下，２００℃以下二茂铁热解成非晶碳纳米管和Ｆｅ／非晶碳纳米同轴电缆。

关键词：溶剂热法合成；碳纳米材料；碳纳米管；多种形貌中图分类号：Ｏ６１１．４；Ｏ６１３．７１文献标识码：Ａ文章编号：１００１－４８６１（２００８）０４－０４９９－０６ＳｏｌｖｏｔｈｅｒｍａｌＳｙｎｔｈｅｓｉｓｏｆＣａｒｂｏｎＮａｎｏｍａｔｅｒｉａｌｓＺＨＵＹｏｎｇ－ＣｈｕｎＱＩＡＮＹｉ－Ｔａｉ＊（ＨｅｆｅｉＮａｔｉｏｎａｌＬａｂｏｒａｔｏｒｙｆｏｒＰｈｙｓｉｃａｌＳｃｉｅｎｃｅｓａｔＭｉｃｒｏｓｃａｌｅａｎｄＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍｉｓｔｒｙ，ＵｎｉｖｅｒｓｉｔｙｏｆＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇｙｏｆＣｈｉｎａ，Ｈｅｆｅｉ２３００２６）Ａｂｓｔｒａｃｔ：Ｃａｒｂｏｎｎａｎｏｍａｔｅｒｉａｌｓｗｉｔｈｄｉｆｆｅｒｅｎｔｍｏｒｐｈｏｌｏｇｉｅｓｗｅｒｅｆａｂｒｉｃａｔｅｄｂｙｓｏｌｖｏｔｈｅｒｍａｌｒｏｕｔｅ，ｉｎｃｌｕｄｉｎｇｖａｒｉｏｕｓｎａｎｏｔｕｂｅｓ，ｎａｎｏｃａｂｌｅｓ，ｎａｎｏｒｏｄｓ，ｎａｎｏｓｐｈｅｒｅｓａｎｄｎａｎｏｃｏｎｅｓ．Ｔｙｐｉｃａｌｌｙ，ｗｈｅｎｈｅｘａｃｈｌｏｒｏｂｅｎｚｅｎｅｗａｓｒｅｄｕｃｅｄｂｙｐｏｔａｓｓｉｕｍａｔ３５０℃ｕｓｉｎｇｄｉｆｆｅｒｅｎｔｃａｔａｌｙｓｔｓ，ｎａｎｏｔｕｂｅｓｏｒｓｐｈｅｒｅｓｗｅｒｅｐｒｅｐａｒｅｄ．Ｉｔｗａｓａｓｓｕｍｅｄｔｈａｔｔｈｅｆｏｒｍａｔｉｏｎｏｆｓｐｈｅｒｅｓｃｏｕｌｄｂｅｅｘｐｌａｉｎｅｄａｓｃｕｒｖｉｎｇｏｆｍａｎｙｓｍａｌｌｇｒａｐｈｉｔｅｆｒａｇｍｅｎｔｓ．Ｂａｍｂｏｏ－ｓｈａｐｅｄａｎｄＹ－ｊｕｎｃｔｉｏｎｃａｒｂｏｎｎａｎｏｔｕｂｅｓｗｅｒｅｓｙｎｔｈｅｓｉｚｅｄｔｈｒｏｕｇｈｒｅｄｕｃｔｉｏｎｏｆｅｔｈａｎｏｌｂｙｍａｇｎｅｓｉｕｍａｔ６００℃．ＷｈｅｎＮａ２ＣＯ３ａｎｄＣＣｌ４ｗｅｒｅｒｅｄｕｃｅｄｂｙｍａｇｎｅｓｉｕｍａｔ５００℃，ｃａｒｂｏｎｎａｎｏｔｕｂｅｓｗｉｔｈａｖｅｒａｇｅｄｉａｍｅｔｅｒｏｆ１００ｎｍｗｅｒｅｏｂｔａｉｎｅｄ．Ｓｏｍｅｄｏｕｂｌｅ－ｈｅｌｉｃａｌｌｙｃｏｉｌｅｄｃａｒｂｏｎｎａｎｏｔｕｂｅｓｗｅｒｅｄｅｔｅｃｔｅｄｂｙｒｅｄｕｃｉｎｇｅｔｈｙｌｅｔｈｅｒｗｉｔｈｍｅｔａｌｌｉｃｚｉｎｃａｔ７００℃．Ａｓｓｉｓｔｅｄｂｙｓｕｌｆｕｒ，ａｍｏｒｐｈｏｕｓｃａｒｂｏｎｎａｎｏｔｕｂｅｓａｎｄＦｅ／Ｃｃｏａｘｉａｌｎａｎｏｃａｂｌｅｓｆｒｏｍｆｅｒｒｏｃｅｎｅｗｅｒｅｏｂｔａｉｎｅｄａｔ２００℃．Ｋｅｙｗｏｒｄｓ：ｓｏｌｖｏｌｔｈｅｒｍａｌｓｙｎｔｈｅｓｉｓ；ｃａｒｂｏｎｎａｎｏｍａｔｅｒｉａｌｓ；ｃａｒｂｏｎｎａｎｏｔｕｂｅｓ；ｄｉｆｆｅｒｅｎｔｍｏｒｐｈｏｌｏｇｉｅｓ０引言自从碳纳米管［１］被发现之后，碳纳米材料的研究成为一个重要且广泛开展的课题。

《纳米材料与纳米技术》论文水热碳化法制备碳纳米材料摘要：水热碳化法是一种重要的碳纳米材料的制备方法，本文综述了近年来以糖类和淀粉等有机物为原料，采用水热碳化法制备各种形貌可控碳纳米材料的研究现状，并提出了该方法研究中存在的问题以及今后可能的发展方向。

关键词：水热碳化法、碳纳米材料、碳微球、碳空心球、核壳结构复合材料1 引言形态可控的碳纳米材料由于独特的结构和性能而受到研究者的普遍关注[1]，常见的制备方法有化学气相沉积法(CVD)[2]、乳液法[3]和水热碳化法[4]等。

水热碳化法是指在水热反应釜中，以有机糖类或者碳水化合物为原料，水为反应介质，在一定温度及压力下，经过一系列复杂反应生成碳材料的过程[5]。

图1为水热碳化法所制备的各种形貌的碳材料。

与其他制备方法相比，采用水热碳化法所制备的纳米碳材料具有显微结构可调、优良的使用性能、产物粒径小而均匀等特点。

本文综述了水热碳化法制备形态可控碳纳米材料的最新研究进展，概括了工艺因素对碳纳米材料合成过程的影响，最后提出了水热法合成碳纳米材料今后可能的研究方向。

图 1 水热碳化法制备各种形貌碳材料的示意图2 水热碳化法制备碳微球碳微球由于具有大的比表面积、高的堆积密度以及良好的稳定性等，被应用于锂离子电池[6]、催化剂载体[7]、化学模板[8]、高强度碳材料[9]等方面，拥有广阔的应用前景。

Yuan等[10]以蔗糖为碳源，先采用水热碳化法合成碳微球，再使用熔融的氢氧化钾溶液对合成产物进行活化处理，制得粒径为100-150nm的碳微球。

研究表明活化后碳微球的石墨化程度有很大提高，且表现出良好的电化学性能。

其比容量达到382F/g，单位面积电容达到19.2μF/cm2，单位体积容量达到383F/cm。

Liu等[11]以琼脂糖为原料，采用水热碳化制备出粒径范围为100～1400nm的碳微球，研究结果表明碳微球的粒径随琼脂糖的浓度的增加而增大，且所制备的碳微球的表面富含大量的含氧官能团，这些官能团可以很好地吸附金属离子或者其它有机物等，因此该材料在生物化学、药物传输以及催化剂载体等方面具有很好的应用前景。

流量开关（Flow switch）Thermal conductivity FS-T thermal flow switch flow indicator is designed based on the principle of heat exchange, probe the built-in heating module and the heat sensing module, heat flow indicator and the measured velocity is closely related to, if not the medium flow pipe, heat heat received sense module is a fixed value, and when the fluid medium through the flow indicator probe, the heat sensing module receives heat and change the flow velocity of medium, the heat sensing module the temperature signal into electrical signal, then the signal processor output into a 4 ~ 20mA signal and the corresponding flow or set. The thermal flow indicator will be integrated flow probe and signal processor integration, six LED lights provide flow trend display, switching value can easily through the front panel of the potentiometer adjustment screw protection, and can provide a transistor, relay and analog output form.The Gems piston type flow switch works on a fluid passage inside the housing with a piston with a permanent magnet inside. When the piston is pushed by the pressure difference caused by the fluid flow, the magnetic piston will switch the sealing reed of the equipment (the sealing reed can be SPST or SPDT, which is related to the model of the product). The diameter of the piston determines the starting flow. When the flow is reduced, the stainless steel spring pushes the piston back. When the reed switch is started, it can be transmitted by remote warning or indication. Or you can integrate it into automatic controlIn system.Working principle：Thermal conductivity flowmeter is designed based on the principle of heat exchange. The probe is equipped with a heating module and a heat sensitive module. The heat of the indicator is closely related to the flow velocity of the fluid on the side. If there is no medium flow pipe, heat heat received sense module is a fixed value, and when the fluid medium flows through the flow indicator probe, sense received thermal module heat changes with the velocity of medium, the heat sensing module and the temperature signal into electrical signal, then contact signal processor the output is converted into the corresponding 4... 20mADC signal or set flow signal corresponding to the.Combine TF series heat flow switch adopts digital circuit design, the product adopts LED display, and uses advanced magnetic ring rotating settings. High reliable design, advanced digital circuit technology, which makes the product anti-interference ability, high measurement accuracy, stability. The full instrument IP65 is constructed with stainless steel housing so that the instrument can be used in any industrial environment.CharacteristicThe digital circuit, intelligent designThe 18 30VAC/DC power supply, can reverse connection...The probe can be replaced, different types of probes are availableYou can select 4 NPN/PNP output, 20mADC output...The big screen blue LCD, showing the percentage of flow, instantaneous flow display can be customizedThe original rotating ring setting functionThe overall degree of protection IP67technical dataThe measuring range: 250cm/s oil: water: 1... 3... 300cm/sGas: 0.3... 3000cm/sOutput: 0/4 - 20mADC or PNP/NPN relay...The sensor length: 15,20,30,40 (mm) according to the needs of othersThe joint: G1/4 (15mm), the other is G1/2, can be customized specialThe power supply: 24VDC + 20% or 220VACThe power: 70mAThe current switch: 400mAThe protection grade: IP67 (EN60529)The connecting cable of PUR materialsThe ambient temperature of 80 DEG C: -20...The medium temperature: 80 degrees -20...The pressure: 40MpaThe starting time: 8 (2... 15) sThe reaction time: 2 (1... 13) sThe adjustment mode: rotating magnetic ring, Holzer effect sensorThe sensor material: ANSI316L food grade stainless steelThe shell material: /ABS stainless steel, ABS plastic ring setThe flow shows: LED, showing the percentage of flow or instantaneous flow customizationThe cable connection: direct head and elbow joint-----------------------------------------------------------------------------------------------如何看清选购流量控制器的方向热式质量流量控制器的选择方法◆常用热式质量流量控制器的种类§通用热式质量流量控制器价格便宜，反应速度较慢s49-33 4秒，s49-32§高性能热式质量流量控制器价格较高，反应速度快s49-31 2秒，s49-30 1秒§金属密封热式质量流量控制器耐污染，多用于大规模成电路制造§数字式热式质量流量控制器反应速度快，可直联计算机§MEMS热式质量流量控制器反应速速最快，不耐污染§其他FCS等◆模拟式流量控制器在挑选时应该注意的几个问题§死区问题§过冲问题§反应速度及电气特性问题◆汇博隆仪器公司在设计中采用的先进技术§内镜面的毛细管§改厚度为0.1mm的极薄0.05mm的毛细管，使热传导透过的速度增加了一倍。

cvd化学气相沉积法英文CVD (Chemical Vapor Deposition) is a type of chemical reaction wherein a solid material is deposited onto asubstrate surface. This process is used in various industrial applications including electronics, semiconductor, and solar cell manufacturing, as well as in the development of coatings, optical fibers, and nanowires. CVD operates under controlled temperature, pressure, and reactant concentrations to deposit a thin layer of material over a defined area. This article aims to discuss the CVD process, particularly the CVDchemical vapor deposition method, in detail.CVD Chemical Vapor Deposition Method:The CVD process involves the following steps:1. Preparing the substrate. The substrate is the surface onto which the material will be deposited. Typically, the substrate is made of silicon, glass, or metals. The surface must be free of contaminants and prepared to promoteadherence of the deposited material.2. Preparation of the reactant gases. The precursorgases are the source of the material to be deposited. The gases are selected based on the desired characteristics ofthe deposited material. The gases are either supplieddirectly to the substrate surface or decomposed into reactive species using thermal energy.3. Activation of the precursor gases. The gases enter a reaction chamber and are heated to high temperatures,typically between 500°C and 1,200°C. This activates the precursors and causes them to decompose into low molecularweight species that react with the substrate surface.4. Deposition of the material. The reactive species created from the precursor gases, now at high temperatures, react with the substrate surface, forming the solid-state product. The thickness of the deposited material can be controlled by adjusting the exposure time, temperature, or precursor gas concentration.5. Monitoring the deposition process. The CVD process is automatically monitored using sensors and feedback control systems. This helps to ensure a uniform and precise deposition of the material onto the substrate surface.CVD chemical vapor deposition has several advantages over other deposition techniques, such as the capability to deposit high-quality thin films of materials with precisely controlled stoichiometry, thickness, and composition. It also has the potential for large-scale production of materials at low cost.In conclusion, the CVD chemical vapor deposition method is a powerful tool in the creation of novel materials, with its capability of producing high-quality thin films of materials with precise control over their composition and thickness. Its applications span across various industries and continue to expand into new, exciting areas. As the technology advances and matures, the CVD process will continue to be at the forefront of material deposition and synthesis.。

常压CVD法合成铌掺杂少层MoS2申赫;王岩岩【摘要】利用粉体NbCl5作为Nb掺杂源,采用常压CVD方法合成了大尺寸Nb 掺杂的少层MoS2薄膜.通过扫描电子显微镜和原子力显微镜观察获得了该薄膜样品的形貌和厚度信息.拉曼光谱和X射线光电子谱测试证实了Nb被掺入到了MoS2薄膜中,Nb掺杂的MoS2合金薄膜已经形成.最后,对Nb掺杂的少层MoS2薄膜的电学性质进行了测试.【期刊名称】《发光学报》【年(卷),期】2018(039)012【总页数】5页(P1654-1658)【关键词】常压CVD;MoS2薄膜;Nb掺杂【作者】申赫;王岩岩【作者单位】吉林师范大学功能材料物理与化学教育部重点实验室, 吉林长春130103;吉林师范大学物理学院, 吉林四平 136000;吉林师范大学环境友好材料制备与应用教育部重点实验室,吉林长春 130103;吉林师范大学化学学院,吉林四平136000【正文语种】中文【中图分类】O484.41 IntroductionLayered transition metal dichalcogenides(TMDCs) such as MoS2, MoSe2, WS2 and WSe2 have recently emerged as promising materials for low cost, flexible and transparent electronics and optoelectronics applications, owing to their unusual physical, optical, and electrical properties arising from the quantum confinement associated to their ultrathin structure[1-4]. For example, MoS2 demonstrates many “graphene-like” properties including a relatively high carrier mobility(a field effect mobility of ～200 cm2·V-1· s-1 for the monolayer), mechanical flexibility(up to 11% strain), chemical and thermal stability, and moreover when the dimension of MoS2 is reduced from a three-dimensional bulk form into a two-dimensional(2D) sheet, the band gap transforms from an indirect to a direct one (Eg of ～1.8 eV for the monolayer), which makes them a semiconducting alternative to gapless graphene[5-6].Doping is widely used to adjust carrier densities and tailor the electronic characteristics of semiconductors, which is more significant in case of 2D materials. The electrical property of monolayer TMDCs materials can be modified by electrostatic doping and adsorption of dopants[3-4,7]. However, the implementation of these methods cannot enable the permanent or stable doping effects in doped layers and is not convenient for practical device applications. Among TMDCs, the doping of MoS2 has been studied earlier and has more basis in the experiments and theoretical descriptions[8-11].Niobium(Nb) has been considered as most promising p-type dopant of MoS2 by calculating the formation energies and the electronic properties of many possible doping element[12]. And theinclusion of Nb into MoS2 occupies part positions of Mo changes little the bond lengths and also the main density of state. Moreover, Nb doping of MoS2 occurs through a substitutional mechanism has also been speculated by using density-functional theory[13]. Note that experimental studies show that Nb-substituted MoS2 nanoparticles and Nb doped MoS2 thin film can be synthesized, and that they also exhibit p-type character[14]. Reference to these results, p-type few-layered MoS2 may be doped by using Nb related chemicals as dopants.An ambient pressure chemical vapor deposition (CVD) growth method for the synthesis of niobium disulfide(NbS2) nanosheets by reacting Niobium chloride(NbCl5) with sulfur(S) vapor has been reported[15]. Coincidentally, CVD method and S vapor are commonly used in the growth of monolayer MoS2 with molybdenum oxide(MoO3). So Nb doped monolayer MoS2 is very hopeful to be obtained in CVD technique by employing MoO3 powder and S powder as Mo and S sources, NbCl5 precursors as Nb dopant sources. However, no experimental report exists for this speculation, which is necessary for demonstration of substitutional doping in few-layered MoS2.In this letter, the Nb doped few-layered MoS2 has been prepared by using an ambient pressure CVD method. Raman spectroscopy, X-ray photoelectron spectrometer(XPS), scanning electronmicroscope(SEM) and atomic force microscope(AFM) imaging indicated that Nb has been doped into MoS2, the size of the doped MoS2 film is up to several millimeters and the thickness of it is only about 1 nm. The conductivity of the Nbdoped few-layered MoS2 is p type.2 ExperimentsThe samples investigated in this letter were all grown inside a quartz-tube in an ambient pressure CVD technique employing Si/SiO2 (285 nm SiO2) as the substrates, the growth schematic is shown in Fig.1. The MoO3 powders were dispersed into ethanol, and then dropped onto the surface of a quartz plate. S and NbCl5 powders in different quartz plates were used as S source and Nb dopant. The substrate was pre-cleaned and placed in the downstream region inside the quartz tube. The quartz tube were mounted on a furnace. The number of red solid circulars indicates different heating temperature. The quartz tube was first evacuated to a base pressure of 100 Pa(1 mbar), followed by a 20 mL/min flow of Ar argon gas(with H2 5%) as carrier gas. The MoO3 heating zone was ramped to 550 ℃ in 20 min, then to 850 ℃ in 40 min, and the S heating zone wa s ramped to 210 ℃ in 40 min. The temperature of MoO3 and S heating zones maintained at 850 ℃ and 210 ℃ for 40 min and 60 min, respectively. NbCl5 powder was put at the edge of S heating zone far away from the substrates. The furnace was cooled to room temperature naturally after the growth. The morphology and the thickness of the Nb doped MoS2 films were measured in a JEOL JSM-6700F field emission scanning electron microscope(SEM) and a Neaspec Atomic force microscopy(AFM). Raman spectrum at excitation wavelength of 532 nm was analyzed in a Renishaw Invia Raman microscope. An AXIS Ultra ‘DLD’ X-ray photoelectron spectrometer(XPS) was used to collected chemical bonding state in thefilms.Fig.1 CVD setup for the growth of the Nb doped few-layered MoS2 alloy 3 Results and DiscussionFig.2 shows the SEM photograph of the Nb doped MoS2 film. The large-scale film has been obtained and the size of it is up to several millimeters. One can see that there are numerous triangle-shaped crystals at the edge of the film, which are the Nb doped MoS2 crystals have not linked up into a film. The height of this film is determined to be only about 1 nm from AFM measurement as shown in the inset.Fig.2 SEM image of the Nb doped few-layered MoS2 alloy, and the inset shows the AFM height signal of the alloy film.The Raman characterization measurements of the Nb doped MoS2 film and triangle-shaped crystal are shown in Fig.3. We can clearly see that the Raman spectra taken from both the film and the triangle-shaped crystal areas show little difference, the two peaks at 361 cm-1 and 400 cm-1 can be attributed to the mode and A1g mode. The peak positions of these two modes are different from the ones of monolayer MoS2 (at about 384 cm-1 and 404 cm-1) and NbS2 nanosheet(at about 327 cm-1 and 386 cm-1)[5-6,15]. It is rational to speculate from the Raman spectrum that these two peaks are mixed with vibration modes of MoS2 and NbS2. Therefore, it can be inferred that our sample is a Nb doped MoS2 alloy.Fig.3 Raman spectra collected from the Nb doped MoS2 film and triangle-shaped crystal areasTo further prove the above speculation, the XPS measurement was carriedout to different areas of the Nb doped MoS2 film, as shown in Fig.4. We can see from the figure that the Nb 3d spectra change little in different areas, which are all close to the spectra of NbxMo1-xS2nanoparticles(x=0.25)[14]. One can deduce from the above data that Nb has been doped into the MoS2 film, the Nb doped MoS2 alloy has been formed. The electrical properties of the film areas were also measured, the Nb dopedFig.4 XPS spectra of Nb 3d in different areas of the Nb doped MoS2 film MoS2 film shows p-type conductivity, but the mobility of this film is only about 2.5 cm2·V-1·s-1, which is much lower than the expected value for the MoS2 monolayer. The low mobility may be influenced by too much Nb doped and also the crystallization quality, that must be improved in the following work.4 ConclusionIn summary, large-scale few-layered Nb doped MoS2 films have been fabricated in an ambient pressure CVD technique by employing NbCl5 as doping precursor. The form of the Nb doped MoS2 alloy films has been confirmed, the conductivity of the obtained films is p-type. We note that although the mobility of these films is still lower than the expected value, this doping method may provide a way to go for efficient p-type MoS2 doping.References:【相关文献】[1] CHUANG H J, TAN X, GHIMIRE N J, et al.. High mobility WSe2 p- and n-type field-effect transistors contacted by highly doped graphene for low-resistance contacts [J]. Nano Lett., 2014, 14(6):3594-3601.[2] CHAKRAVARTY S, HOSSEINI A, XU X, et al.. Analysis of ultra-high sensitivity configuration in chip-integrated photonic crystal microcavity bio-sensors [J]. Appl. Phys. Lett., 2014, 104(19):4654-4650.[3] BAUGHER B W H, CHURCHILL H O H, YANG Y, et al.. Optoelectronic devices based on electrically tunable p-n diodes in a monolayer dichalcogenide [J]. Nat. Nanotechnol., 2014, 9:262.[4] MOURI S, MIYAUCHI Y, MATSUDA K. Tunable photoluminescence of monolayerMoS2via chemical doping [J]. Nano Lett., 2013, 13(12):5944-5948.[5] YOON J, PARK W, BAE G Y, et al.. Highly flexible and transparent multilayer MoS2 transistors with graphene electrodes [J]. Small, 2013, 9(19):3295-3300.[6] LIN Y C, ZHANG W, HUANG J K, et al.. Wafer-scale MoS2 thin layers prepared by MoO3 sulfurization [J]. Nanoscale, 2012, 4(20):6637-6641.[7] ROSS J S, KLEMENT P, JONES A M, et al.. Electrically tunable excitonic light-emitting diodes based on monolayer WSe2 p-n junctions [J]. Nat. Nanotechnol., 2014, 9:268. [8] FUHR J D, SAL A, SOFO J O. Scanning tunneling microscopy chemical signature of point defects on the MoS2 (0001) surface [J]. Phys. Rev. Lett., 2004, 92(2):026802.[9] HE J, WU K, SA R, et al.. Magnetic properties of nonmetal atoms absorbed MoS2 monolayers [J]. Appl. Phys. Lett., 2010, 96(8):082504.[10] CHENG Y C, ZHU Z Y, MI W B, et al.. Prediction of two-dimensional diluted magnetic semiconductors: doped monolayer MoS2 systems [J]. Phys. Rev. B, 2013, 87(10):1214-1222.[11] ATACA C, CIRACI S. Functionalization of single layer MoS2 honeycomb structures [J]. J. Phys. Chem. C, 2011, 115(27):13303-13311.[12] DOLUI K, RUNGGER I, PEMMARAJU C D, et al.. Possible doping strategies for MoS2 monolayers: an ab initio study [J]. Phys. Rev. B, 2013, 88(7):4192-4198.[13] IVANOVSKAYA V V, ZOBELLI A, GLOTER A, et al.. Ab initio study of bilateral doping within the MoS2 -NbS2 system [J]. Phys. Rev. B, 2008, 78(13):134104-1-7.[14] FRANCIS LEONARD D, HAGAI C, SIDNEY C, et al.. Fullerene-like (IF) NbxMo1-xS2 nanoparticles [J]. J. Am. Chem. Soc., 2007, 129(41):12549-12562.[15] WANYIN G, KENJI K, MASAHARU T, et al.. Large-scale synthesis of NbS2 nanosheets with controlled orientation on graphene by ambient pressure CVD [J]. Nanoscale, 2013,5(13):5773-5778.。

Hydrothermal synthesis of NaA zeolite membrane together withmicrowave heating and conventional heatingAisheng Huang a,⁎,Weishen Yang baDepartment of Chemistry,Tongji University,Shanghai 200092,ChinabState Key Laboratory of Catalysis,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian 116023,ChinaReceived 25January 2007;accepted 2April 2007Available online 19April 2007AbstractUniform and dense NaA zeolite membrane was prepared by hydrothermal synthesis method together with microwave heating and conventional heating.The properties of the as-synthesized zeolite membrane were investigated by XRD,SEM and pervaporation evaluation for dehydration of 95wt.%isopropanol/water mixture at 343K,respectively.After microwave heating,the α-Al 2O 3support surface was covered with homogeneous zeolite nuclei,which facilitated to form uniform,pure and dense NaA zeolite membrane in the following conventional heating process.High quality NaA zeolite membrane,i.e.,with a separation factor (water/isopropanol)of 10,000and a flux of 1.44Kg/(m 2h),could be hydrothermal synthesized together with microwave heating and conventional heating.©2007Elsevier B.V .All rights reserved.Keywords:Composite materials;Crystal growth;Thin film1.IntroductionIn the last two decades,many efforts have been made aiming to synthesis and application of the zeolite membranes for their excellent properties.Several synthesis strategies and methods have been developed,such as in-situ hydrothermal synthesis [1–4],secondary growth [5–7],vapor phase transport [8],dry gel conversion [9]and microwave synthesis [10].The in-situ hydro-thermal synthesis is the best-studied method,in which the porous support is immersed into the synthesis solution,and then the membrane is formed by direct crystallization.However,in this method the quality of the as-synthesized membrane significantly depends on the characteristics of the support surface [11].It is usually difficult to prepare high quality zeolite membrane by in-situ hydrothermal synthesis directly.The secondary growth method,which firstly proposed by Lovallo et al.[5],exhibits many advantages,such as better control over membrane micro-structure (thickness,orientation)and higher reproducibility [7,12].Recently,a new synthesis method named microwave syn-thesis has been developed for synthesis of zeolite membranes.Compared with the conventional hydrothermal synthesis,micro-wave synthesis exhibits many advantages,including a very short synthesis time,uniform and small crystal sizes and broad syn-thesis composition.Up to date,LTA [10,13],Sodalite [14],FAU [15],MFI [16],SAPO-5[17]and AlPO4-5[18]zeolite mem-branes have been synthesized by microwave synthesis method.However,It is not easy to prepare high performance zeolite membranes only by use of microwave synthesis.Recently,It was also proved that in-situ aging is necessary for microwave syn-thesis of LTA zeolite membrane without seeding [13].In this paper,we report a novel synthesis stratagem for hydro-thermal synthesis of NaA zeolite membrane together with micro-wave heating and conventional heating.The effect of microwave heating procedure on the membrane formation and pervaporation properties of the NaA zeolite membrane is investigated.2.Experimental2.1.Synthesis of NaA zeolite membraneSchematic diagram for the synthesis of NaA zeolite membrane together with microwave heating and conventional heating is illustrated schematically in Fig.1.Porous α-Al 2O 3Available online at Materials Letters 61(2007)5129–5132/locate/matlet⁎Corresponding author.Tel.:+8602165988570;fax:+8602165982287.E-mail address:huangash@ (A.Huang).0167-577X/$-see front matter ©2007Elsevier B.V .All rights reserved.doi:10.1016/j.matlet.2007.04.017tube (home-made:11mm in outer diameter,7mm in inner diameter,70mm in length,0.5∼1.0μm pore radius,about 40%porosity)was used as supports.The outer surface of the support was polished with 700grit sand papers and was cleaned several times with deionized water in a Branson SB2200ultrasonic cleaner.Before hydrothermal synthesis,the cleaned support was calcined in air at 673K for 3h.The solution for synthesizing NaA zeolite membrane was prepared according to the procedure reported previously [12].The aluminate solution was prepared by dissolving sodium hydroxide in deionized water,then adding aluminum foil to the solution at room temperature.The silicate solution was prepared by mixing silica sol and deionized water at 333K with vigorous stirring.After 10min of stirring,the preheated aluminate solution was added with stirring to produce a clear and homogenous solution.The molar ratio of this mixture solution was 50Na 2O:Al 2O 3:5SiO 2:1000H 2O.The α-Al 2O 3support was sealed with two Teflon caps at both the ends and placed vertically in a Teflon autoclave.The synthesis solution was poured into the autoclave and the auto-clave was sealed.Before conventional heating,the autoclave was put in a microwave oven (Haier,HR-8801M)with a working frequency of 2450MHz.The synthesis solution was quickly heated to 363K and then held at invariable temperature for 25min.After microwave synthesis,the autoclave was put in an air oven immediately and the crystallization was carried out.After crystallizing 4h at 363K,the solution was decanted off and the membrane was thoroughly washed with deionized water,and then dried in air at 423K for 3h.2.2.Characterization of NaA zeolite membraneThe structure of the as-synthesized zeolite membrane was confirmed by X-ray diffraction (XRD)patterns.XRD was carried out on a Rigaku D max/rB power diffractometer using CuK αradiation operating at 40Kv and 50mA.The morphology and thickness of the as-synthesized zeolite membrane were examined by scanning electron microscopy (SEM).The SEMphotographs were obtained on a JEM-1200E scanning electron microscopy.The pervaporation properties were evaluated for dehydration of 95wt.%isopropanol/water mixtures at 343K.The apparatus used for the pervaporation experiments is illustrated schemat-ically in elsewhere [19].The isopropanol/water mixtures were fed to the out side of the zeolite membrane in the membrane model.The inside of the membrane was evacuated with a vacuum pump.Two cold traps with liquid N 2cooling were used to collect the permeate.The compositions of the feed and the permeate were analyzed by gas chromatogram (HP5890).The total flux (J),the component flux (J i )and the separation factor (α)are defined as respectively:J ¼WD tA J i ¼Jx i ;p a i 1j ¼x i ;p x i ;f d x j ;f x i ;nWhere W is total weight of the permeate (Kg),Δt is collecting time (h),A is separation area of the membrane,x i ,p is the weight fraction of species i in the permeate and x i ,f is the weight fraction of species i in the feed.3.Results and discussionFig.2a and b shows the XRD pattern of the as-synthesized zeolite membrane prepared with 25min microwave heating and with the following 4h conventional heating,respectively.As shown in Fig.2a,the peaks of NaA zeolite appeared besides those of α-Al 2O 3support,indicated purity NaA zeolite layer was formed on support surface after microwave heating.As shown in Fig.2b,It can be seen that the intensity of the peaks of the NaA zeolite increased after the following 4h conventional heating,contributing to a further growth of the NaA zeolite layer.In addition,no peaks other than those of NaA zeolite and α-Al 2O 3support were detected in the as-synthesized membrane,indicating high pure NaA zeolite membrane could be prepared together with microwave heating and conventional heating.One explanation is large numbers of zeolite particles are rapidly produced with microwave heating,thus supplying more nucleus centers on the support surface,which are benefit to restrain from forming impure crystallinephase.Fig.1.Schematic diagram for synthesis of NaA zeolite membrane together with microwave heating and conventional heatingmethod.Fig.2.XRD pattern of the NaA zeolite membrane:(a)XRD pattern of the NaA zeolite membrane:(a)prepared with microwave heating;(b)prepared together with microwave heating and conventional heating;(c)prepared with conventional heating.(n )NaA zeolite,(x )hydroxy-sodalite zeolite,(•)α-Al 2O 3.5130 A.Huang,W.Yang /Materials Letters 61(2007)5129–5132Fig.3a and b show the SEM images of the as-synthesized NaA zeolite membrane after microwave heating.As shown in Fig.3a and b, after microwave synthesis,the support was covered with uniform and small zeolite particles,with crystals size of about2∼3μm,but there were no continuous zeolite membrane formed judged by the image of the cross-section.Fig.3c and d show the SEM images of the as-synthesized NaA zeolite membrane prepared with the following4h conventional heating.As shown in Fig.3c and d,after the following hydrothermal synthesis,the support surface was completely covered with uniform and compact NaA zeolite crystals.The zeolite crystals were found to be highly inter-grown and no observable inter-crystalline gaps presented.The surface of the as-synthesized membrane was very smooth with a thickness of about10μm as revealed from the cross-section.Fig.2c show the XRD pattern of the as-synthesized zeolite membrane directly prepared with4h conventional heating.It can be seen that,some crystal phase other than those of NaA zeolite andα-Al2O3support were detected,which indicated that NaA zeolite crystals transformed to other types crystals.Fig.3e and f show the SEM images of the NaA zeolite membrane directly prepared with4h conventional heating.As shown in Fig.3e and f,the crystals sizes were not uniform, and some of these larger zeolite crystals seem almost detached from the zeolite layer.The growth of zeolite crystals on the support surface seems to be less ordered in the direct hydrothermal synthesis,and the surface of the as-synthesized membrane was very rough and loose. Moreover,it can be seen that cabbage-like spherical crystals as well as octahedral crystals was formed among the cubic NaA zeolite crystals, indicating that NaA zeolite crystals transformed to other typescrystals. Fig.3.SEM images of the NaA zeolite membrane:(a)(b)prepared with microwave heating;(c)(d)prepared together with microwave heating and conventional heating;(e)(f)prepared with conventional heating.5131A.Huang,W.Yang/Materials Letters61(2007)5129–5132This observation was in good agreement with the XRD patterns of the NaA zeolite membrane.Table1shows pervaporation properties of the as-synthesized mem-brane.As shown in Table1,after25min microwave heating at363K, the as-synthesized NaA zeolite membrane exhibit poor pervaporation properties,i.e.,the separation factor(water/isopropanol)was only28.5 although the flux was high to3.16Kg/(m2h).When the following4h conventional heating was carried out,the pervaporation properties of the as-synthesized membrane improved.The separation factor(water/ isopropanol)increases to10,000,and the flux was1.44Kg/(m2h). When the as-synthesized zeolite membrane was directly prepared by hydrothermal synthesis method,there was no dense membrane formed on the support surface and NaA zeolite crystals transformed to other crystals.These resulted in poor pervaporation properties of the as-synthesized membrane compared with that prepared together with microwave heating and conventional heating.The separation factor (water/isopropanol)and flux was171and1.59Kg/(m2h),respectively.4.ConclusionUniform and dense NaA zeolite membranes were prepared on theα-Al2O3support together with microwave heating and conventional heating.Theα-Al2O3support surface was covered with homogeneous zeolite nuclei after microwave heating,and the abundant zeolite nuclei facilitated to form uniform,pure and dense NaA zeolite membrane in the following conventional heating process.The as-synthesized NaA zeolite membrane exhibited good pervaporation properties,i.e.,with the separa-tion factor(water/isopropanol)of10,000and the flux of 1.44Kg/(m2h).AcknowledgementsThis work was supported by the National Science Founda-tion of China(20607015)and Program for Young Excellent Talents in Tongji University(2006KJ057).References[1]Y.Yan,M.E.Davis,G.R.Gavalas,Ind.Eng.Chem.Res.34(1995)165.[2]J.Sterte,S.Mintova,G.Zhang,B.J.Schoeman,Zeolites18(1997)387.[3]T.Sano,H.Yanagishita,Y.Kiyozumi,et al.,J.Membr.Sci.95(1994)221.[4]M.Kondo,M.Komori,H.Kita,K.I.Okamota,J.Membr.Sci.133(1997)133.[5]M.C.Lovallo,M.Tsapatsis,AICHE J.42(1996)3020.[6]i,G.R.Gavalas,Ind.Eng.Chem.Res.37(1998)4275.[7]L.C.Boudreau,J.A.Kuck,M.Tsapatsis,J.Membr.Sci.152(1999)41.[8]J.Dong,T.Dow,X.Zhao,L.Gao,mun.(1992)1056.[9]Y.H.Ma,Y.J.Zhou,R.Poladi,E.Engwall,Sep.Purif.Technol.25(2001)235.[10]X.C.Xu,W.S.Yang,J.Liu,L.W.Lin,Adv.Mater.12(3)(2000)195.[11]V.Valtchev,S.Mintova,Zeolites15(1995)171.[12]A.S.Huang,Y.S.Lin,W.S.Yang,J.Membr.Sci.245(2004)41.[13]Y.Li,H.Chen,J.Liu,W.Yang,J.Membr.Sci.277(2006)230.[14]A.Julbe,J.Motuzas,F.Cazevielle,G.V olle,Sep.Purfi.Technol.32(2003)139.[15]K.Weh,M.Noack,I.Sieber,J.Caro,Microporous Mesoporous Mater.54(2002)27.[16]J.Motuzas,A.Julbe,R.D.Noble,et al.,Microporous Mesoporous Mater.92(2006)259.[17]T.Tsai,H.Shih,S.Liao,K.Chao,Microporous Mesoporous Mater.22(1998)333.[18]S.Mintova,S.Mo,T.Bein,Chem.Mater.10(1998)4030.[19]A.S.Huang,W.S.Yang,Microporous Mesoporous Mater.102(2007)58.Table1Pervaporation properties of the as-synthesized zeolite membrane Codes Synthesis method Properties of the membranesMembrane thickness(μm)αwater/isopropanol Flux(kg/m2h)1MH for25min at363K/28.5 3.162MH for25min+CHfor4h at363K1010,000 1.443CH for4h at363K11171 1.594[12]Secondary growth24h333K1210,000 1.385[19]EPD for6h at363K73281 1.24MH:microwave heating;CH:conventional heating.5132 A.Huang,W.Yang/Materials Letters61(2007)5129–5132。

第53卷第2期2024年2月人㊀工㊀晶㊀体㊀学㊀报JOURNAL OF SYNTHETIC CRYSTALSVol.53㊀No.2February,2024高温高压合成掺杂金刚石研究进展郝敬林1,2,邓丽芬2,王凯悦1,宋㊀惠2,江㊀南2,西村一仁2(1.太原科技大学材料科学与工程学院,太原㊀030024;2.中国科学院宁波材料技术与工程研究所,海洋材料及相关技术重点实验室,浙江省海洋材料与防护技术重点实验室,宁波㊀315201)摘要:金刚石具有超高热导率㊁宽禁带等优点,通过掺杂引入电子和空穴等缺陷,提升载流子浓度,可以使金刚石具有适合半导体应用的电导率,被称为第三代终极宽禁带半导体材料㊂本文首先介绍了金刚石单晶的高温高压合成方法,接着系统综述了基于高温高压法的金刚石掺杂研究现状和发展,然后分析了N㊁B㊁P和S等单元素掺杂及多元素共掺杂对金刚石晶体生长和电学性能的影响,并且对第一性原理计算研究金刚石掺杂进行了分析总结㊂高温高压退火可以有效改变金刚石中掺杂元素与空位等缺陷组合和分布状态,本文明晰了金刚石中含氮色心形成的原因及高温高压退火对色心的调控机制㊂最后对金刚石掺杂以及掺杂后金刚石的光学性能和电学性能研究前景进行了展望,指出可进一步探索多元素共掺杂的理论与实验方法,对提升掺杂金刚石性能具有重要意义㊂关键词:金刚石;高温高压;掺杂;含氮色心;退火;第一性原理计算中图分类号:O78;TQ163㊀㊀文献标志码:A㊀㊀文章编号:1000-985X(2024)02-0194-16 Synthesis of Doped Diamond by High-Pressure andHigh-Temperature:a ReviewHAO Jinglin1,2,DENG Lifen2,WANG Kaiyue1,SONG Hui2,JIANG Nan2,KAZUHITO Nishimura2(1.School of Materials Science and Engineering,Taiyuan University of Science and Technology,Taiyuan030024,China;2.Zhejiang Key Laboratory of Marine Materials and Protective Technologies,Key Laboratory of Marine Materials and Related Technologies,Ningbo Institute of Materials Technology and Engineering,Chinese Academy of Sciences,Ningbo315201,China) Abstract:Diamond possesses an ultra-high thermal conductivity and a wide band-gap.Its electrical resistance could be adjusted for the semiconductor application by increasing the electron and vacancy content introduced by doping different elements.Therefore,diamond is thought to be the final wide band-gap semiconductor materials.This paper firstly introduces the synthesis of diamond by high-pressure and high-temperature(HPHT)method,and then systematically reviews the current status and developments of diamond doping by HPHT.The effects of single-element doping,such as N,B,P,and S,as well as multi-elements co-doping in the diamond crystal growth and its electrical properties are analyzed.In additional,this paper summaries the study diamond doping using first-principle calculation.HPHT annealing could effectively change the combinations of doped elements and the associated vacancies and their distribution.This paper reviews the adjustment of nitrogen-related color centers in diamond by HPHT annealing,elucidating the formation mechanisms of various nitrogen-related color centers.Finally,This paper prospects the potential optical and electrical properties of doped diamonds,highlighting the importance of theoretical calculations and experimental methods for multi-element co-doping investigation to enhance the performance of doped diamonds.Key words:diamond;HPHT;doping;nitrogen-vacancy center;annealing;first-principle calculation㊀㊀收稿日期:2023-08-16㊀㊀基金项目:国家重点研发计划(2022YFB3706602,2021YFB3701801);宁波市重点科技项目(2022Z191);宁波市甬江人才引进计划(2021A-037-C,2021A-108-G);中国科学院青年基金(JCPYJ-22030);宁波市重大科技攻关专项(2021ZDYF020196);中国科学院项目(ZDKYYQ2020001)㊀㊀作者简介:郝敬林(1998 ),男,江苏省人,硕士研究生㊂E-mail:haojinglin@㊀㊀通信作者:邓丽芬,博士,教授级高工㊂E-mail:denglifen@王凯悦,博士,教授㊂E-mail:wangkaiyue8@宋㊀惠,博士,副研究员㊂E-mail:songhui@㊀第2期郝敬林等:高温高压合成掺杂金刚石研究进展195㊀0㊀引㊀㊀言金刚石是一种重要的功能材料,其高硬度(60~120GPa)[1]㊁高热导率(20W㊃K-1㊃cm-1)[2]㊁宽波段透光率和较高的介质击穿场强(5~10MV/cm)[2]等性能使其在大功率半导体热沉片[3]㊁高端光学窗口[4]等领域得到广泛应用㊂纯净的金刚石是良好的绝缘体,晶体内无自由电子,具有宽禁带(5.47eV)[2],因而电阻率很高㊂但是当金刚石中有其他掺杂元素存在时,电阻率会大幅下降,成为半导体材料㊂随着信息产业化的发展,对半导体材料提出了更高的要求,常规的半导体材料已经不能满足市场的需求,金刚石的优异性能使其在半导体领域有广阔的应用前景[3]㊂金刚石的合成方法主要分为高温高压(high pressure and high temperature,HPHT)法[5]和化学气相沉积(chemical vapor deposition,CVD)法[6]㊂其中,高温高压法采用温度梯度(temperature gradient method, TGM)[7]控制碳溶解㊁扩散和再结晶在籽晶上生长㊂高温高压法合成过程中易于添加不同物质,从而将不同元素掺杂进入金刚石晶格,因此成为研究金刚石掺杂的主要方法㊂通过元素掺杂发掘金刚石的功能特性,可拓宽其应用范围㊂除了高温高压法外,其他一些方法也可以实现金刚石的掺杂,比如CVD法㊁电子束辐照法和离子注入法等㊂但是,CVD法的掺杂元素受限,很多元素例如Ge等金属元素由于其自身特性难以被掺入㊂另外,CVD法掺硼通常需要采用有剧毒的硼烷气体,因而掺硼金刚石的应用受到限制㊂离子注入法掺杂则对晶格的破坏较大㊂综合而言,高温高压是一种较为成熟和有效的金刚石掺杂方法㊂为了突破金刚石在电学㊁光学等方面的应用限制,研究人员尝试通过掺杂改变其性质,进而拓展其应用范围,尤其是电学应用,可以分别通过施主杂质和受主杂质掺杂来制造低电阻率n型和p型金刚石㊂金刚石的掺杂元素目前主要有B㊁N㊁S㊁P等,其中,硼原子半径较小,硼掺杂p型半导体金刚石在理论和实验方面都取得了进展,而且随着电学性能的改善,可以利用线切割对其进行加工,为金刚石刀具加工提供了途径㊂对于p型硼掺杂金刚石,掺入0.1%(摩尔分数,下同)的硼源后其电阻率最小已达到10-2Ω㊃cm[8],仅就电阻率而言已达到器件制作的要求㊂然而宽带隙材料难以实现两级掺杂[9],目前电阻率最低的n型金刚石只能达到102Ω㊃cm[10],因而极大地限制了金刚石在电学领域的应用,金刚石的n型掺杂比p型更具挑战性[11]㊂近年来,为了在金刚石的n型掺杂方面取得进展,研究者主要致力于N㊁P㊁S等元素的掺杂研究[12]㊂本文在对高温高压合成金刚石大单晶的基本原理及工艺进行介绍的基础上,对金刚石的元素掺杂及其电学与光学性质等研究进展进行了归纳总结,分析了当前研究的热点问题,以便更好了解行业的发展状况㊂1㊀金刚石合成方法石墨与金刚石都是碳的同素异形体,在碳的压强-温度(pressure-temperature,P-T)相图中都有所表现[13],图1分别展示了金刚石和石墨的稳定区㊂在高温高压条件下,金刚石单晶的生长是通过石墨到金刚石的相变实现的㊂石墨经过高温高压作用后会变成金刚石,并在金刚石种子上沉积形成新的金刚石单晶㊂因此,金刚石单晶的生长需要有适当的种子晶体作为生长的起点㊂1970年,美国通用电气公司(GE)在高温高压下利用温度梯度法合成金刚石大单晶,成为材料领域的重要突破[7]㊂迄今为止,温度梯度法仍然是目前国内外合成金刚石大单晶最为常见和有效的方法㊂石墨作为碳源位于腔体中的高温端,晶种位于低温端㊂由于两者之间存在温差而形成了温度梯度㊂在高温高压下,高温处的碳源转化为金刚石,并在一定温度梯度的生长驱动下从高温端向低温端扩散,并在低温区的晶种处结晶析出(见图2)㊂温度梯度法的生长驱动力与轴向温度梯度成正比,可以通过调整金刚石合成块的组装结构,进而把控温度梯度的生长驱动力,实现对合成金刚石生长速度的控制[14]㊂196㊀综合评述人工晶体学报㊀㊀㊀㊀㊀㊀第53卷图1㊀碳元素的P-T 相图Fig.1㊀P-T phase diagram of carbon element 图2㊀温度梯度法原理示意图[15]Fig.2㊀Schematic diagram of diamond synthesis by temperature gradient method [15]2㊀金刚石单晶的掺杂金刚石单晶掺杂主要分为两种类型:替位式掺杂和间隙式掺杂[16]㊂替位式掺杂是将金刚石中的一些碳原子替换成其他原子,如氮㊁硼㊁硅等㊂目前针对金刚石薄膜的掺杂在国内外研究较多,而对高温高压下金刚石大单晶的掺杂研究较少㊂金刚石常见的掺杂形式有单元素掺杂和多元素协同掺杂,其中,单元素掺杂的掺杂剂可以使是单质,也可以是化合物,而多元素掺杂有双掺或三掺,主要以双掺为主㊂2.1㊀金刚石单一掺杂2.1.1㊀硼掺杂硼原子半径小,容易进入金刚石内部,因此在掺杂p 型半导体金刚石薄膜[17]的研究中有大量关于掺杂硼的文献并获得了实际应用[18]㊂对于掺硼金刚石单晶来说,硼的添加会对金刚石单晶的形貌和电学性能产生影响㊂2005年,张健琼等[19]通过加入无定形硼粉,在高温高压下成功合成出掺硼金刚石单晶,并且晶体中硼的含量随着合成温度的升高而降低㊂在合成过程中硼元素优先从金刚石的{111}扇区进入晶体,在扇区内部金刚石的生长速度逐渐减小,硼元素扩散逃离可用时间越来越长,最终导致硼元素含量不均匀,呈内多外少的分布规律[20]㊂掺硼金刚石单晶的晶体特征如表1所示㊂表1㊀掺硼宝石级金刚石单晶的晶体特征[20]Table 1㊀Crystal characteristics of boron-added gem-quality diamond single crystals [20]SampleGrowth crystal phase Boron (mole fraction)/%Growth time /h Crystal weight /mg Crystal size /mm a {100} 1.03 1.1 1.3b{100} 2.51032.2 3.4c {111} 1.03128.5 5.4d {111} 2.51071.9 4.4在(100)面生长掺单质硼的金刚石单晶时,晶体表面呈现出黑色三角形的对称区域,不同区域的硼含量存在差异㊂随着硼添加量的增加,{111}面的生长区域变宽,而{100}面的生长区域变窄直至几乎消失[21]㊂此外,在{100}㊁{111}和{311}扇区内也存在不均匀性㊂通过PL 光谱可以发现,与硼和氮有关的缺陷以及与空位相关的缺陷集中分布在与生长区边界相交的辐照区㊂在{311}扇区发现了在富B 和富N 生长之间交替的带,639㊁651和658.5nm 处的B 相关中心在{311}扇区中比在{100}或{111}扇区中更强㊂648nm 中心在富B 的{111}扇区中最强,在{311}扇区中较弱,在{100}扇区中更弱(见图3)[22]㊂硼掺杂金刚石单晶的掺杂效果主要表现为导电性的改变㊂在高温高压下,硼原子取代金刚石单晶中的碳原子,形成硼掺杂金刚石单晶㊂硼原子的加入使金刚石单晶中的空穴浓度增加,从而提高了材料的导电性㊂硼掺杂金刚石单晶的导电性与硼的浓度和掺杂方式有关,通过控制硼源的含量和反应条件,可以实现不㊀第2期郝敬林等:高温高压合成掺杂金刚石研究进展197㊀同浓度和不同类型的硼掺杂金刚石单晶㊂高温高压技术可以实现高表面积㊁低材料电阻和多孔电极结构,通过循环伏安法(cyclic voltammetry)可以证明掺硼金刚石的电极具有比非多孔电极更高的双层电容[23]㊂使用密度泛函理论(DFT)对重掺杂硼金刚石进行电子结构计算,结果表明B中心之间的相互作用直接决定了空穴的密度,对费米能级的位置和电子行为有着重要影响㊂当温度降到临界温度时,理论计算显示出向超导体转变的趋势,而且临界温度和B的浓度相关[24]㊂虚拟晶体近似法也正确地预测了硼掺杂金刚石中电子-声子耦合的主要特征,为这种材料的超导性提供了一个非常简单和直观的解释,提出了通过具有强共价键的空穴掺杂材料寻找高温超导体的有用的新途径[25]㊂Shakhov等[26]使用Ni-Mn催化剂在高压高温条件下合成的掺硼金刚石室温电导率可达1Ω-1㊃cm-1,但是由于硼对金刚石生长的阻碍作用和杂质化合物的存在而未实现超导电性㊂重掺硼金刚石单晶的超导性能研究前景广阔,值得深入研究㊂图3㊀488nm激发下的PL光谱[22]Fig.3㊀PL spectra under488nm laser excitation[22]2.1.2㊀氮掺杂氮是金刚石中最为常见的杂质元素,根据金刚石中氮含量的不同可以将其分为I型金刚石和II型金刚石,如表2所示㊂表2㊀金刚石的分类及性质[27]Table2㊀Classification and properties of diamond[27]Type Nature diamond Nitrogen impurities/10-6Color Resistance/(Ω㊃cm) Ia98%2ˑ103aggregate state Colorless,yellow104~1016Ib0.1%10~103dispersive state Yellow,brown104~1016IIa1%~2%<1Colorless104~1016IIbʈ0%<1,B-doped Blue10~104氮在金刚石晶体中有多种存在形式,氮原子与由辐射损伤引入的空位形成了多种缺陷中心,从而导致金刚石呈现不同颜色,所以通常被称为色心,如表3所示㊂杂质引起的色心主要包括:C中心(孤氮中心)[28-29]㊁A中心和B中心[28,30]㊁N3-N2中心[31-32]㊂其中A中心和B中心不直接影响金刚石的颜色,又称为198㊀综合评述人工晶体学报㊀㊀㊀㊀㊀㊀第53卷 间接色心 ㊂辐射损伤引起的色心主要包括:GR1中心[28,33]㊁595中心[28-29]㊁H3和H4中心[28-29]㊁3H中心[29,34]㊁N-V中心[28]㊁NDl中心[35]㊁S1中心[35]等㊂其中,部分色心(如孤氮中心)直接成为金刚石颜色的诱导因素,有些色心组合的形成致使金刚石呈色㊂表3㊀金刚石氮杂质中心Table3㊀Diamond N impurity centersDefect centerλmax/nm Color ReasonC-center560Yellow Caused by impurities[28-29]N3-center415.5Yellow Caused by impurities[31-32]N2-center478Yellow Radiation damage[31-32]GR1-center741Blue,green Radiation damage[28,33]595-center425Yellow High temperature annealing600~800ħafter radiation damage[28-29] H3-center503Yellow,brown High temperature annealing800ħafter radiation damage[28-29] H4-center496Yellow,brown High temperature annealing800ħafter radiation damage[28-29] 3H-center504Yellow Heat treatment after radiation damage350~400ħ[29,34]NV0-center575Pink Radiation damage[28]NV--center637Pink,red Radiation damage[28]NDl-center388 Radiation damage[35]S1-center515~520Blue-green,yellow-green Radiation damage[35]氮在常温下以气体形式存在,所以氮的化合物常用来作为掺杂所用的氮源㊂常见的氮源有NaN3㊁C3H6N6和Fe3N等㊂通过向石墨和铁粉中添加叠氮化钠(NaN3),成功地将氮掺杂到了金刚石中,合成了氮浓度高达(1000~2200)ˑ10-6的金刚石单晶,其氮含量与天然金刚石相同[36]㊂金刚石中的氮浓度随着NaN3含量的增加而增加,但是当NaN3的含量增加到0.7%~1.3%(摩尔分数,下同)时,金刚石中的氮浓度几乎保持在1250ˑ10-6至2200ˑ10-6的范围内㊂同样,使用C3H6N6合成的金刚石的最高氮含量为2300ˑ10-6,其分解的氮效应降低了金刚石的生长速率并将其颜色改变为绿色[37]㊂NaN3和C3H6N6掺杂含量与氮含量的对应关系如图4所示,NaN3的掺杂含量在0.5%之前阶段氮含量持续增高,0.5%~0.7%阶段氮含量降低,1.0%前后变化趋势也存在此类情况㊂而C3H6N6则是随着掺杂含量的增加,氮含量稳步升高到2300ˑ10-6,仍未见饱和平台区出现㊂根据以上情况,若是合成高氮金刚石单晶,则选择C3H6N6作为掺杂剂可实现更高的氮含量㊂合成压力和退火时间不足导致氢不被金刚石吸收,随着C3H6N6含量的增加,金刚石的颜色由黄色变为绿色㊂拉曼光谱表明,以C3H6N6为掺杂剂合成的金刚石晶体缺陷较少,实验结果如表4所示㊂为了研究氮浓度对金刚石结晶过程和金刚石晶体结构的影响,Palyanov等[38]在Fe-Ni系统中加入Fe3N和CaCN2两种不同的氮浓度增长体系㊂在金刚石的热力学稳定性范围内,随着金属熔体中氮浓度的增加,位错㊁孪晶片层和内部应变的密度增加㊂当氮浓度高于某一临界值(0.4%)时,金刚石的成核和生长终止,石墨结晶㊂表4㊀掺杂C3H6N6金刚石在5.6GPa作用下处理11h的实验结果[37]Table4㊀Experimental results of doped C3H6N6diamond treated for11h in the presence of5.6GPa[37]Sample Temperature/K C3H6N6/%Morphology Growth rate/(mg㊃h-1)a15130(100)+(111)+(110)8.72b15130.05(100)+(111)+(110) 6.11c15130.10Twin crystal 2.57d15130.15(100)+(111) 1.80e15130.20(100)+(111) 1.65f15130.25(100)+(111) 1.06a 15530(100)+(111)+(110)7.93b 15530.05(100)+(111)+(110) 6.53c 15530.10Twin crystal 5.88d 15530.15(100)+(111) 3.69e 15530.20(100)+(111) 2.33f 15530.25(100)+(111) 1.15㊀第2期郝敬林等:高温高压合成掺杂金刚石研究进展199㊀图4㊀NaN3和C3H6N6掺杂含量与氮含量的关系[36-37]Fig.4㊀Relationship between NaN3and C3H6N6doping content and nitrogen content[36-37]由于高氮含量金黄色金刚石的稀有和广受欢迎,以及色心NV-的量子效应,金刚石的氮掺杂研究一直是热点,高温高压退火可以改变金刚石中氮状态㊂高氮金刚石((1500~1700)ˑ10-6)在退火后1h内,由于金刚石晶格中氮的聚集,晶体的颜色明显由绿色变到无色(见图5)[39]㊂含氮施主原子在(1500~1600)ˑ10-6的金刚石晶体退火后使原来以单取代态(C中心)排列的氮原子转变为对取代态(A中心),一小部分氮原子仍以C中心形式存在,而一些A中心形式的氮原子进一步转变为N3和H3中心结构[40]㊂退火降低了高氮金刚石中NV-中心的浓度㊂相反,低氮含量的金刚石退火后可产生较高浓度的NV-色心㊂尽管高温高压条件下金刚石中存在许多缺陷的NV色心影响,但低氮含量金刚石在高温高压条件下直接退火是合成NV色心的一种简便方法[41]㊂这些发现对了解氮原子以聚集形式存在的天然Ia型金刚石的形成机制有很大帮助㊂图5㊀高浓度掺氮金刚石晶体的光学图像[39]Fig.5㊀Optical images of highly concentrated nitrogen-doped diamond crystals[39]通过第一性原理计算发现,金刚石中氮以C中心的形式存在会使带隙值(5.5eV)稍有降低,并预测由于C中心引起的光吸收在3eV左右[42]㊂理论上氮掺杂可以引入杂质能级,改变金刚石的导电性和光学吸收性能,从而提高其光学发光效率㊂但是氮在金刚石晶格中能级深,位于导带最小值以下1.7eV处,因而掺氮金刚石电阻率高,难以获得符合要求的n型金刚石半导体材料[43]㊂200㊀综合评述人工晶体学报㊀㊀㊀㊀㊀㊀第53卷2.1.3㊀硫掺杂硫的原子半径大,进入到金刚石晶格中有一定的困难,但硫是研究合成n型半导体金刚石的重要掺杂剂之一㊂通过第一性原理计算对掺杂浓度为3.12500%㊁1.56000%和0.78125%(摩尔分数,下同)的硫掺杂金刚石的能带结构和电子结构的研究发现,不同浓度下能带结构和电子结构的变化基本类似,硫杂质缺陷的电离能为0.3eV,表现为n型导电[44]㊂2011年,周林等[45]在NiMnCo催化体系中成功合成掺杂硫金刚石单晶,合成的金刚石晶体具有完整的{100}和{111}面,内部有少量的包裹体㊂Chen等[46]在Fe-Ni-C体系中加入高纯硫粉合成了硫掺杂的IIa型金刚石单晶,随着硫含量的增加生长速率明显降低㊂合成体系中的硫会促进NV0和NV-中心出现在金刚石晶格中㊂在该系统下合成的硫掺杂Ib型金刚石单晶在沿{111}面生长更容易出现氮空位(NV)中心,氮杂质浓度如表5所示㊂与NV-中心相比,在不添加硫的情况下,Ib型金刚石晶格中不容易生成NV0中心㊂虽然在添加0.25%硫的情况下同时生成NV0和NV-中心,但NV-峰的强度明显高于NV0峰[47],氮空位的光致发光光谱如图6所示㊂表5㊀FeNi-S-C体系合成Ib型金刚石及氮杂质的浓度[47]Table5㊀Synthesis of Ib-type diamond and concentration of nitrogen impurities by FeNi-S-C system[47]Sample S/%Growth face Growth rate/(mg㊃h-1)Nitrogen content/10-6a0{100}0.280151b0.10{100}0.157201c0.25{100}0.070144d0{111}0.186180e0.10{111}0.153230f0.25{111}0.062154图6㊀FeNi-S-C系金刚石晶体的光致发光光谱[47]Fig.6㊀PL spectra of FeNi-S-C system diamond crystals[47]使用四探针和霍尔效应法可以表征掺硫金刚石单晶的电学性能㊂研究发现,随着硫含量的增加(1.0%~4.0%),所合成金刚石单晶的半导体性能也有所提高㊂当金刚石晶胞中的硫含量达到4.0%时,金刚石的电阻为9.628ˑ105Ω㊃cm,为进一步合成n型半导体金刚石提供了依据[48]㊂同样,使用FeS和NiS作为硫源也可以制备出n型半导体金刚石单晶,合成样品的半导体性能也随着硫含量的增加而增强,如表6所示㊂二者制备出的样品最低电阻率分别为8.131ˑ105和11.630ˑ105Ω㊃cm,可见FeS掺杂得到的金刚石单晶电阻率最小[49-50]㊂表6㊀不同硫源掺杂金刚石的电学性能Table6㊀Electrical properties of diamond after doping with different sulfur sourcesSulfur source Doping method Minimum resistivity/(Ω㊃cm)CharacteristicSulfur powder[48]Substitute9.628ˑ105n-typeFeS[49]Substitute8.131ˑ105n-typeNiS[50]Substitute11.630ˑ105n-type㊀第2期郝敬林等:高温高压合成掺杂金刚石研究进展201㊀2.1.4㊀磷掺杂磷的原子半径较大,很难进入金刚石晶格中㊂当磷原子在金刚石晶格中取代一个碳原子时,将会引起晶胞的膨胀,晶格会发生畸变,对金刚石晶胞的构型㊁键型和电荷的空间分布都会产生一定的影响㊂聂媛等[51]选用Fe3P作为磷源进行磷掺杂金刚石单晶的合成,磷源含量和晶体形貌如图7所示㊂随着Fe3P的含量增加,金刚石晶体中氮含量上升,说明磷的进入诱使氮原子更容易进入金刚石晶格中㊂同时,金刚石晶体的颜色逐渐变深,包裹体的数量逐渐增加,晶形由板状转变为塔状直至骸晶,在拉曼光谱下可以看到其半峰全宽变大,晶格畸变增加㊂在FeNiMnCo-C体系中掺入单质磷合成了片状金刚石晶体[52],随着磷含量的增加,金刚石晶体的生长速率逐渐降低,温度区间也明显增大㊂并且通过四点探针和霍尔效应法测试发现磷掺杂金刚石大单晶的最小电阻率为3.561ˑ106Ω㊃cm㊂同样,研究人员以Mn3P2作为掺杂剂在FeNi体系下合成了金刚石晶体㊂Mn3P2的加入改变了催化剂的催化性能,使金刚石晶体生长的V形区在1230~1245ħ明显向右上方移动[53]㊂掺杂后的样品通过电学性能测试表明其电阻率为0.516ˑ106Ω㊃cm,霍尔系数为负,与前者相比电学性能得到了极大的提高,对n型半导体的研究很有帮助㊂图7㊀沿(111)面合成磷掺杂金刚石显微光学照片[51]Fig.7㊀Micro-optical photograph of P-doped diamond synthesized along(111)surface[51]通过第一性原理的方法计算了磷掺杂浓度的金刚石晶格的电子结构[54]㊂不同浓度磷原子取代碳原子前后的杂质激活能及总能量差的变化如表7所示,一个磷原子取代一个碳原子所引起的能量差值(ΔE=E2-E1)随着掺杂磷原子浓度的增加而降低,可能是由于掺杂元素浓度的升高使得晶格膨胀加剧,原子间的松弛引起了一部分电子和原子核之间的相互作用减弱㊂杂质原子的掺杂浓度越高金刚石晶格的膨胀越严重,晶体里的sp3杂化的碳键就越不稳定,越容易向sp2碳键转化㊂虽然高掺杂时可以获得合适的电导率,但会严重损伤金刚石晶格[54]㊂磷掺杂的n型金刚石半导体材料的载流子浓度和电子迁移率相对较低,导致其电阻率较高,因此需要进一步研究以获得具有良好电学性能的n型金刚石半导体材料㊂掺磷金刚石单晶的合成研究较少,尤其是磷与其他元素共掺杂合成方面的研究需要加强㊂表7㊀磷掺杂金刚石晶格的能量变化[54]Table7㊀Energy variation of P-doped diamond lattice[54]Number of cell atom Total energy before doping,E1/eV Total energy after doping,E2/eV Energy difference,ΔE/eV 16-2.478ˑ103-2.498ˑ103-0.0195ˑ10324-3.717ˑ103-3.737ˑ103-0.0193ˑ10332-4.957ˑ103-4.976ˑ103-0.0191ˑ10348-7.435ˑ103-7.454ˑ103-0.0190ˑ10364-9.913ˑ103-9.932ˑ103-0.0188ˑ10372-1.115ˑ103-1.117ˑ103-0.0189ˑ10396-1.487ˑ103-1.489ˑ103-0.0187ˑ103 2.1.5㊀其他单元素掺杂除了上述的四种常见的元素外,还有很多元素可以进行掺杂㊂Sittas等[55]在高温高压条件下首次合成掺硅金刚石单晶,并且只有在IIa型金刚石中才能发现掺杂的硅空位㊂对{001}㊁{111}㊁{113}生长区进行202㊀综合评述人工晶体学报㊀㊀㊀㊀㊀㊀第53卷光谱分析,发现硅中心的分布很不均匀,硅中心的发射强度不依赖于生长扇区㊂硅粉加入到镍基金属催化剂后,随着硅含量的增加,金刚石内部夹杂物从点状到片状再到串状分布,最终难以生长出完整的晶体[56]㊂硅的加入不仅增加了晶体内部的应力,使金刚石的结晶质量变差,而且也降低了金刚石中氮的浓度㊂同时,生长体系中的氮杂质也阻碍了金刚石中硅的有效掺杂㊂同样,在Ni-Mn-C体系中也可以将镁作为掺杂剂来评价其对晶体生长机制和缺陷的影响㊂如表8和图8所示,当Mg的含量为2%(摩尔分数,下同)时,金刚石晶体表面平整,有利于其在刀具中应用㊂添加3%和4%Mg的样品没有出现任何明显的变化,添加量为5%时晶体出现了夹杂物,这表明镁的添加量确实影响这些晶体表面缺陷的数量㊂在所用的高温高压参数下,晶体结构普遍为八面体㊂当Mg的含量为2%时,晶体产率较高,3%~5%的成核速率较小,生长速率降低[57]㊂表8㊀掺Mg样品在(1250ʃ50)ħ条件下的晶体参数[57]Table8㊀Crystal parameters of Mg-doped samples at(1250ʃ50)ħ[57]Sample Mg/%Crystal weight/mg Growth rate/(mg㊃h-1)a10.223 4.46b20.124 2.48c30.052 1.04d40.099 1.98e50.278 5.56图8㊀不同镁掺杂量金刚石晶体的SEM照片[57]Fig.8㊀SEM images of diamond crystals with different amounts of Mg doping[57] Palyanov等[58]在Mg-Ge-C体系下成功地合成了Ge掺杂单晶金刚石,在光致发光光谱中存在大量的2.06eV的Ge-V中心,如图9(a)所示㊂在该体系中加入的Ge抑制了金刚石自发成核的强度,从而可以通过晶种生长出相对较大(2~3mm)的金刚石单晶㊂在不同的合成条件下,合成的金刚石晶体从2.06eV中心到一级拉曼散射线的光致发光强度范围可达几个数量级,证明了Mg-Ge-C体系生长同位素修饰锗掺杂的块体低应变金刚石晶体的可行性,为进一步研究金刚石中锗相关色心的性质及其作为单光子源的可能应用提供了依据㊂2019年,相关研究人员在FeSnAl-C㊁Sn-(Ti,Al,Zr)-C和Sn-Mg-C三种条件下进行锡的掺杂对比实验[59]㊂研究发现,由Fe-Sn-Al组成的Fe基催化剂合成的金刚石没有与Sn相关的光学中心,在Sn-C系统中证实了在生长过程中Sn原子在金刚石晶格中的掺入原则上是可能的,但是生长系统中的氮杂质阻碍了Sn的有效掺杂,而且这些氮杂质很难用除氮剂消除㊂用Sn-Mg催化剂合成的金刚石单晶在光致发光光谱中显示出明显的Sn-V色心特征,如图9(b)所示㊂高温高压下成功合成了Sn掺杂金刚石,在量子技术应用中取得进一步进展㊂。

氮化硼纳米片的制备及其应用研究进展杜淼;李阳;张光荣【摘要】近些年,氮化硼纳米片越来越受到人们的重视.与石墨烯相比,氮化硼纳米片具有耐高温、宽带隙以及更好的抗氧化性等优异的性能.这些优异的力学、电学和光学等性质使氮化硼纳米片在某些领域比石墨烯具有更好的应用前景.结合近几年国内外研究现状,综述了机械剥离法、化学气相沉积法和液相插层剥离法等3种制备氮化硼纳米片的方法,并分析了各种方法的优点和不足之处.介绍了氮化硼纳米片的应用研究进展,并对其未来的发展做了展望.【期刊名称】《无机盐工业》【年(卷),期】2019(051)002【总页数】4页(P8-10,34)【关键词】氮化硼;纳米片;石墨烯;化学气相沉积法【作者】杜淼;李阳;张光荣【作者单位】齐鲁师范学院化学与化工学院,山东济南250200;山东师范大学化学化工与材料科学学院;齐鲁师范学院化学与化工学院,山东济南250200;齐鲁师范学院化学与化工学院,山东济南250200【正文语种】中文【中图分类】TQ128.1氮化硼（boron nitride，BN）是由Ⅲ族的硼原子和Ⅴ族的氮原子组成的一种重要的Ⅲ-Ⅴ族化合物。

因为硼原子与氮原子采用不同的混合方式，所以形成了几种不同的晶型，比较常见的有2 种杂化方式：sp2 杂化和sp3 杂化。

sp2 杂化的BN 主要包含六方氮化硼（h-BN）和三方氮化硼（r-BN）；sp3 杂化的BN 主要包含立方氮化硼（c-BN）和纤锌矿氮化硼（w-BN）。

氮化硼纳米片（boron nitride nanosheets，BNNSs）是由多个六元环的硼吖嗪（borazine）所构成，与石墨烯互为等电子体［1］。

由于BNNSs 的颜色为白色，所以也称为“白石墨烯”或“硼墨烯”。

BNNSs 的上下层之间存在较弱的范德华力，层间的叠加属于AA′堆积，即硼原子和氮原子沿c 轴依次交错排列，而石墨烯层间则是半六边形的叠加属于AB 堆积，如图1所示［2］。

热丝化学气相沉积金刚石膜温度场的仿真模拟与应用黎韩琪;栗正新;苑执中【摘要】热丝化学气相沉积( HFCVD)是大面积生长金刚石膜的有效方法，在生长过程中衬底温度的高低和均匀性是影响金刚石膜生长的关键因素。

本文综述了国内外学者针对HFCVD法沉积金刚石膜的温度场模拟和优化工艺参数的研究成果，指出了目前存在的问题，提出了下一步的发展方向。

%Hot-filament chemical vapor deposition ( HFCVD) is an effective method for large area diamond film growth. In the process of growing,the uniformity of temperature and the temperature of the substrate are the key factors. The progress of research for thermal field simulation and parameter optimization on large area diamond film growth by HFCVD is summarized in this article. Moreover, the existing problems and development on it are put forward in this pa-per.【期刊名称】《中原工学院学报》【年(卷),期】2015(000)003【总页数】5页(P64-67,79)【关键词】热丝化学气相沉积;金刚石膜;温度场;模拟;综述【作者】黎韩琪;栗正新;苑执中【作者单位】河南工业大学材料科学与工程学院，郑州450001;河南工业大学材料科学与工程学院，郑州450001;台钻科技有限责任公司，郑州450016【正文语种】中文【中图分类】TQ164热丝气相化学沉积(HFCVD)是最早采用的生长金刚石膜的方法之一，生产成本低、设备简单、生产过程容易控制、产品膜层质量好，是金刚石薄膜产业化发展与应用的最有效的方法之一[1]。

第34 7期2018年7月无机化学学报CHINESE JOURNAL OF INORGANIC CHEMISTRYVol.34 No.71327-1332纳米锰基普鲁士白的制备及电化学储钠性能陈新1徐丽1沈志龙2刘双宇1李慧1王博1谢健!，2姜银珠2刘海镇1盛鹏1赵广耀1全球能源互联网研究院有限公司，先进输电技术国家重点实验室，北京1022117(2浙江大学材料科学与工程学院，杭州3100277摘要：采用高温共沉淀法制备锰基菱方相的普鲁士白正极材料，研究合成温度对产物微结构和电化学性能的影响。

研究发现，随着合成温度的提高，产物的结晶度、颗粒尺寸和嵌钠容量明显提高。

当合成温度为90 "时，产物在M m A j-1下首次充放电容量分别达到142和U A m A lv i-1。

在30和'O m A.g-1分别循环300和600次时，容量仍保持在111和SAm Ah.g-1。

关键词：钠离子电池（正极材料（普鲁士白（电化学性能中图分类号：TB34 文献标识码：A 文章编号！1001-4861(2018)07-1327-06DOI：10.11862/CJIC.2018.177Preparation and Electrochemical Performance of theNanostructure Mn-Based Prussian WhiteCHEN Xin1XU Li1SHEN Zhi-Long2LIU Shuang-Yu1LI Hui1WANG Bo1XIE Jian!，2JIANG Yin-Zhu2LIU Hai-Zhen1SHENG Peng1ZHAO Guang-Yao1(^State Key Laboratory of A dvanced Transmission Technology, Global Energy InterconnectionResearch Institute Co. Ltd” Beijing 102211, China)(^School of M aterials Science and Engineering, Zhejiang University, Hangzhou310027, China) Abstract：Rhombohedral phase Mn-based Prussian white materials were synthesized by high-temperature coprecipitation method and the effect of synthesis temperature on the microstructure and electrochemical performance of the products was investigated. It is found that the crystallinity，particle size and Na-insertion capacity increase obviously with the increasing synthesis temperature. At a synthesis temperature of 90 "，the first charge and discharge capacities of the product reach 142 and 139 mAh'g-1at 15 mA'g-1.After 300 cycles at 30 mA'g-1 and 600 cycles at 50 mA'g-1，the discharge capacities are kept at 111 and 89 mAh'g-1，respectively. Keywords：sodium-ion batteries; cathode materials; Prussian white; electrochemical performance0引言随着能源和的日重，开发清洁、可持续能已成为球的研究[16。

吸附束缚(cvd法)硅烷气中的硅英文回答：CVD (Chemical Vapor Deposition) is a widely used technique for the synthesis of silicon films. In CVD,silicon is deposited from a gas phase onto a substrate, forming a thin film. One of the commonly used precursorsfor silicon deposition is silane gas (SiH4). Silane gas is introduced into a reaction chamber, where it undergoes thermal decomposition to produce silicon atoms. Thesesilicon atoms then adsorb onto the surface of the substrate, leading to the formation of a silicon film.The adsorption of silicon atoms from silane gas ontothe substrate surface is a crucial step in the CVD process. It involves the interaction between the silicon atoms and the substrate surface, which can be influenced by various factors such as temperature, pressure, and the nature ofthe substrate. The adsorption process can be described by the Langmuir adsorption isotherm, which relates the surfacecoverage of adsorbates to the gas pressure.The adsorption of silicon atoms onto the substrate surface is a reversible process. Once the silicon atoms are adsorbed, they can also desorb back into the gas phase. The balance between adsorption and desorption determines the coverage of silicon atoms on the substrate surface. By controlling the process parameters, such as temperature and pressure, it is possible to optimize the adsorption and achieve the desired coverage of silicon atoms.中文回答：化学气相沉积（CVD）是一种广泛应用的合成硅薄膜的技术。

碳化硅纳米颗粒增强环氧树脂付新【摘要】SiC nanoparticles were prepared by the carbon thermal reduction method,in which furfuryl alcohol and tetraethoxysilane (TEOS) were respectively employed as carbon and silica precursors. Polym-ethylhydrosiloxane (PMHS) was employed as pore-adjusting agent.XRD,TEM, DLS were used to characterize the SiC samples. The results showed that the SiC nanoparticles with dimensions in the range of 10 ~50 nm can be finally obtained. The SiC nanoparticles with smaller size have better reinforcement effect in epoxy resin.%以糠醇为碳源,正硅酸乙酯为硅源,含氢硅油为结构助剂,通过碳热还原的方法制备出碳化硅纳米颗粒,采用XRD、TEM、DLS对样品进行表征.结果表明,所得碳化硅纳米颗粒尺度分布在10～50nm,其增强的环氧树脂,拉伸强度和压缩强度均有明显提高.【期刊名称】《应用化工》【年(卷),期】2012(041)008【总页数】3页(P1479-1481)【关键词】碳化硅纳米颗粒;碳热还原;环氧树脂【作者】付新【作者单位】渭南师范学院化学与生命科学学院,陕西渭南714000【正文语种】中文【中图分类】TQ050.4碳化硅(SiC)是一种性能优异的半导体材料，具有很多优异的性能，例如禁带宽度大、热传导率高、热稳定性强、抗氧化及耐腐蚀等。

博览I 成果简报Review Achievements二维纳米防护薄膜材料研制取得进展石墨烯具有大的比表面积、高的化学惰性以及优异的阻隔性，被认为是已知最薄的防护材料，采用化学气相沉积（CVD ）法制备的石墨烯薄膜可直接用于 金属的腐蚀防护，逐渐成为制备石墨烯防护薄膜最主 要的方法。

但石墨烯薄膜在制备过程不可避免会引入 空位、晶界等结构缺陷，将其长时间暴露在空气中，腐蚀介质容易通过这些缺陷与基底金属发生反应，且高导电的石墨烯薄膜将促进界面处的电化学反应进而 加速基底金属的腐蚀。

近期，中国科学院宁波材料技术与工程研究所海 洋新材料与应用技术重点实验室研究员王立平团队利 用CVD 技术在多晶铜衬底上成功制备了一系列的氮掺图1氮掺杂石墨烯薄膜的长效腐蚀防护机理Monolayer 另一方面，六方氮化硼（h-BN ）纳米片作为一种 石墨烯类似物，也具有很好的抗渗透性。

王立平团队通过CVD 法在多晶铜衬底上生长出不同层数的h-BN 薄膜，由于h-BN 自身的绝缘特性，无论是单层或是多层h-BN 薄膜，将其包覆在铜衬底表面都表现出优异的大 气长效防护性能。

在高温加热条件下（200C ），单层h-BN 薄膜包覆铜箔的氧化主要发生在薄膜晶界和缺陷 处，而多层h-BN 的氧化主要集中在薄膜的褶皱区；相 比于单层h-BN 薄膜，多层h-BN 薄膜能够有效阻碍氧 气的横向扩散，显著提高了基底铜的抗氧化性能（图2 ）。

相关结果发表在ACS Applied Materials & Interfaces （2017, 9, 27152-27165）上。

以上研究工作得到中科院前沿科学重点研究项目（QYZDY-SSW-JSC009）、国家自然科学基金 （41506098）、青岛海洋科学与技术国家实验室开放 基金（QNLM2016ORP0409 ）等的资助。

杂石墨烯薄膜，通过调节NH3的气流量获得不同氮浓 度的氮掺杂石墨烯薄膜。