化学气相淀积制备Si3N4超细粉末

本文研究了ＳｉＣｌ４－ＮＨ３－Ｎ２－Ｈ２系统平衡热力学，确定了Ｓｉ３Ｎ４合成的最佳热力学条件。采用电阻炉化学气相淀积法制备了Ｓｉ３Ｎ４超细粉末，并考察了工艺条件对颗粒形貌的影响。     

CVD金刚石薄膜(111)与(100)取向生长的热力学分析

用非平衡热力学耦合模型计算了CVD金刚石薄膜生长过程中C2H2与CH3浓度之比[C2H2]/[CH3]随衬底温度和CH4浓度的变化关系,从理论上探讨了金刚石薄膜（111）面和（100）面取向生长与淀积条件的关系。在衬底温度和CH4浓度由低到高的变化过程中,[C2H2]/[CH3]逐渐升高,导致金刚石薄膜的形貌从（111）晶面转为（100）晶面。添加氧后C2H2与CH3浓度都将下降,但C2H2下降得更多,因而添加氧也使[C2H2]/[CH3]下降,从而有利于生长（111）晶面的金刚石薄膜。     

超细粉末的制备技术

超细粉末是新材料的重要组成部分,研制超细粉末是发展现代高科技的需要。本文综述了当今世界各国用于制备超细粉末的固相法、气相法和液相法的特点和分类。     

湿法制备羟基磷灰石生物活性陶瓷粉末的热力学分析

本文对制备羟基磷灰石的Ｃａ（ＮＯ３）２－（ＮＨ４）２ＨＰＯ４－ＮＨ４ＯＨ－Ｈ２ＯＬ体系进行热力学分析。计算求得ＨＡ沉淀最宜ｐＨ条件为１０．６－１２．４，热力学计算与实验结果和文献报告数据结果一致。     

气相还原法制备α—Fe超细粉末

本文介绍了气相还原法制备α－Ｆｅ超细粉末的原理及过程，对α－Ｆ超细粉末特性进行了初步表征。     

气相还原法制备α—Fe超细粉末试验工艺研究

探讨了气相还原法制备超细α－Ｆｅ粉末的工艺过程，经过试验研究和理论分析给出了一组较低佳的工艺参数。     

气相还原法制备α－Fe超细粉末

本文介绍了气相还原法制备α－Ｆｅ超细粉末的原理及过程，对α－Ｆｅ超细粉末物性进行了初步表征。     

Preparation of nanocrystalline SnO2 thin film coated Al2O3 ultrafine particles by fluidized chemical vapor deposition

Fluidized chemical vapor deposition (FCVD) technology was developed for coating SnO₂ thin film on Al₂O₃ ultrafine particles. TEM and HREM analysis found that SnO₂ films with different structures were deposited by controlling the coating temperature, reactant concentration, etc. Nanocrystalline SnO₂ film was coated at 573.15 K by gas phase reaction of SnCl₄ with H₂O. EPMA and EDS studies indicated that the distribution of SnO₂ inner and outer of the agglomerates was uniform. Nucleation and film deposition were coexisted mechanism during the FCVD coating process. The fraction of SnO₂ in the composite particles increased with increasing coating temperature, SnCl₄ concentration, and coating time. The mass fraction of SnO₂ in the composite particles increased strongly with the ratio of P_H2O and P_SnCl4 at low mole ratio of H₂O with SnCl₄, but increased little under the conditions of excess H₂O with respect to SnCl₄.     

金刚石薄膜中晶粒尺寸的研究

扫描电子显微研究表明，化学汽相沉积的金刚石薄膜中晶粒大小比较均匀。但随着沉积时间和薄膜厚度的增加，晶粒逐渐变大，且每一层内，存在少量的大金刚石颗粒，讨论了晶粒尺寸变化和大晶粒形成的原因和机制。     

Preparation and electrochemical properties of nitrogen-doped multi-walled carbon nanotubes

High yield bamboo-shaped N-doped multi-walled carbon nanotubes (MWNTs), containing 2.27 at.% N, were fabricated by pyrolysis of pyridine at 800 °C in an Ar atmosphere. The electrochemical capacitive performances of this type of carbon fiber were evaluated in 6 M KOH aqueous solution. The specific capacitance of N-doped MWNT electrode is measured to be 44.3 F/g at the charge/discharge current of 1 mA, which is two times greater than that of the undoped one (19.9 F/g). The measurements also reveal that the N-doped MWNT electrode possesses lower equivalent series resistance (0.24 Ω) and higher knee frequency (1995 Hz) than the undoped one. This improvement is attributed to the unique morphology and electronic properties of N-doped MWNTs.     

Thermodynamic study on co-deposition of ZrB2-SiC from ZrCl4-BCl3-CH3SiCl3-H2-Ar system

Thermodynamics phase diagram of ZrB₂-SiC co-deposited from precursors of ZrCl₄-BCl₃-CH₃SiCl₃ (methyltrichlorosilane, MTS)-H₂-Ar has been investigated in detail by using the FactSage code and its embedded database (130 species being involved). The yields of condensed phases in the co-deposition process have been examined as the functions of the inject reactant ratios of BCl₃ / (BCl₃ + MTS) and H₂ / (ZrCl₄ + BCl₃ + MTS), and the temperature at a fixed pressure of 5 kPa. The results show that their yields strongly depend on the molar ratios of the inject reactants and the temperature. Consequently, the pure ZrB₂-SiC composite without free C, B₄C, ZrC and ZrSi can be co-deposited under the ideal condition by adjusting the reactant ratios and the temperature. The gas-phase equilibrium concentration distribution shows that the high input amount of H₂ is favorable for the co-deposition of ZrB₂ and SiC at a fixed ratio of ZrCl₄:BCl₃:MTS:Ar. In the end, the theoretical results can lay down guidelines for increasing the experimental yields of ZrB₂ and SiC.     

化学气相沉积制备钼钨合金

以MoF6、WF6以及H2为原料,用化学气相共沉积的方法,成功地在铜基片表面沉积出钼钨合金.实验分析表明:沉积层结构为单相均匀固溶体.在钼含量高时沉积层显微组织呈细晶层状结构,在钼含量较低时沉积层显微组织呈柱状晶生长.改变反应气体中WF6、MoF6相对含量可实现膜层成分可控.采用化学气相沉积法沉积钼钨等难熔金属合金,沉积纯度高,设备简单,沉积速率快,在高温抗烧蚀涂层及耐腐蚀涂层方面具有广泛的应用前景.     

乙炔催化裂解制备碳纳米带及其结构表征

以乙炔（C2H2）为碳源,铁为催化剂,通过化学气相沉积技术在单晶硅衬底上制备了碳纳米带.采用场发射SEM、TEM、激光Raman光谱等先进分析手段对其形态和结构进行了表征.研究发现：碳纳米带是一种准二维材料,厚度约30nm,宽度在几百纳米,长度在100μm量级.碳纳米带的碳层沿着与其生长轴方向一致的（002）晶向排列,碳层的边缘都弯曲折叠成封闭结构.碳纳米带中碳层的排列不很平直,其中存在大量的层错.由此认为碳纳米带可用于能源等领域.     

化学气相沉积法制备碳纳米管

碳纳米管（CNTs）是一种具有独特理化性能和结构的一维纳米材料,也是当今纳米材料研究的焦点之一．在化学、生物、医药、能源、电子元件等诸多领域具有极高的应用价值．本文以有机溶剂环己烷为碳源．利用化学气相沉积法（CⅥ））在管式电阻炉内,以氩气为栽气,二茂铁为催化剂,一定温度条件下,制备了直径约为50nm,长度达几十微米以上的多壁碳纳米管（MWNTs）．采用拉曼光谱、扫描电镜、透射电镜、X-射线粉末衍射等测试手段,表征了碳纳米管的微观形貌和结构特征．通过对实验结果的分析和讨论,对CVD制备法中碳纳米管的生长机理进行了尝试性探讨。     

Preparation and characterization of carbon molecular sieves from chestnut shell by chemical vapor deposition

In this study, carbon molecular sieves (CMS) were produced from chestnut shell by chemical activation process followed by chemical vapor deposition (CVD) of methane. The influences of deposition temperature (800–900?°C), time (15–60?min) and flow rate of CH₄ (100–300?mL/min) on pore development of carbon molecular sieve were investigated. The produced CMSs were characterized by several techniques such as N₂ adsorption, CO₂ adsorption, CH₄ adsorption, elemental analysis, FTIR analysis and SEM analysis. The textural analysis of the CMS samples showed the successful deposition of methane on pores of the produced activated carbon derived from chestnut shell to yield a microporous CMS with a narrow pore size distribution. The deposition temperature, time and flow rate of CH₄ were shown to strongly affect the pore structure of the CMS. The maximum CO₂ adsorption capacity (525.7?mg/g) was obtained at a deposition temperature of 850?°C, time of 30?min, and CH₄ flow rate of 100?mL/min.     

毫米级长定向碳纤维阵列的制备

本文通过在固体二茂铁前驱体中添加少量硫粉,利用浮动催化化学气相沉积法制得了高纯度,直径和长度均一、且笔直定向、长达数毫米的碳纤维阵列.研究了反应温度和硫在碳纤维形成过程中的作用.用扫描电子显微镜和透射电子显微镜分析了碳纤维的结构.