WC/TiO_2纳米复合材料的微结构及性能研究  

Microstructure Characterization and Electrocatalytic Properties of WC/TiO_2 Nanocomposites

作　　者：郑遗凡[1,2] 陆月萍[1,2] 莫卫民[1,2] 李国华[2] 赵娜[1,2] 

机构地区：[1]浙江工业大学分析测试中心,杭州310014 [2]浙江工业大学化学工程与材料学院,杭州310014

出　　处：《无机材料学报》2010年第11期1139-1144,共6页Journal of Inorganic Materials

基　　金：浙江省自然科学基金(Y4080209;Y406094);浙江省科技计划项目(2007F70039)~~

摘　　要：以纳米TiO2为载体,偏钨酸铵为钨源,经机械球磨后制备成WC/TiO2前驱体,将前驱体在900℃,甲烷/氢气气氛下碳化还原,获得了系列WC/TiO2纳米复合材料.采用XRD、SEM、HRTEM、STEM-Z衬度像、EDS-Mapping方法对样品的晶相、微观结构、化学成份及空间分布进行了系统表征;采用三电极体系粉末微电极方法测试了样品在碱性溶液中的电化学催化活性,结果表明:随着碳化还原时间的延长,样品中钨的物相由WO3→WO2→W→W2C、WC发生变化;碳化钨晶粒在20 nm以下且分布于载体TiO2表面;还原碳化6h样品电化学性能最佳,此时活性相以WC和W2C为主,晶粒最细且均匀分布于稳定的金红石载体表面.WC/TiO2 precursor was fabricated by ball-milling a mixture of titania and ammonium metatungstate, then WC/TiO2 nanocomposites were obtained after carbonization under CH4/H2 atmosphere at 900℃. The as-prepared samples were characterized by XRD, SEM, HRTEM, STEM and EDX, and their electrocatalytic activities were measured by microelectrode approach with three electrodes in basic solution. The results show that the crystal phase of tungsten species in the samples changes according to the following order： WO3→WO2→W→W2C or WC in the carbonization process. The tungsten carbide nanoparticles, which are decorated on the surface of titania, generally have a diameter less than 20 nm. The sample carbonized for 6h mainly have two catalytic active phases of very small size, namely WC and W2C, which are uniformly dispersed on the surface of TiO2 particles. The electrocatalytic measurement shows the sample is most active.

关 键 词：碳化钨 二氧化钛 纳米复合材料 微结构表征 

分 类 号：TQ174[化学工程—陶瓷工业]