WC/CNT纳米复合材料制备及其对甲醇氧化的电催化性能

采用表面修饰技术将碳纳米管(CNT)表面羧基化, 通过羧基将钨离子基团修饰到碳纳米管的外表面, 再通过原位还原碳化技术, 将钨离子基团还原成碳化钨(WC)纳米微粒, 制备出WC/CNT纳米复合材料. 采用FTIR、XRD、SEM、HRTEM和N2吸附等分析测试手段对样品的形貌、晶相组成和微观结构特征进行了表征. FTIR和N2吸附结果表明, 硝化后, 在碳纳米管表面羧基化的同时比表面积增加; XRD结果表明, WC/CNT样品由碳纳米管、WC以及非化学计量比的氧化钨组成; SEM和HRTEM结果表明, WC纳米颗粒均匀地分散于碳纳米管的外表面,并与碳纳米管构成了复合材料. 采用循环伏安法测试了样品在碱性条件下对甲醇氧化的电催化性能, 结果表明, 复合材料对甲醇氧化的电催性能明显强于WC 和碳纳米管, 并在实验结果的基础上探讨了复合材料催化性能提高的原因.

Preparation and Electrocatalytic Property for Methanol Oxidation of WC/CNT Nanocomposite

In order to fabricate WC/CNT nanocomposite,carbon nanotubes(CNTs)were first surface decorated by carboxy groups,and tungsten ionic groups were decorated on the surface of carbon nanotube through carboxy groups, then the tungsten ionic groups were reduced into tungsten carbide by an approach of in situ reduction and carbonization.The samples were characterized by FTIR,XRD,SEM,HRTEM,and N_2 adsorption.FTIR and N_2 adsorption results showed that the decorated carbon nanotube was of carboxylation,while its specific surface area increased.XRD results showed that the sample was composed of tungsten carbide(WC),carbon nanotube and non- stoichiometric tungsten oxide.SEM and HRTEM results showed that the tungsten carbide nanoparticles with irregular granular laid on the outer surface of carbon nanotube homogenously.The electrocatalytic activity of the samples was tested by powder-microelectrode,and the results showed that the electrocatalytic activity of the sample for methanol oxidation in basic solution was higher than that of hollow microsphere tungsten carbide with mesoporosity and purified carbon nanotube.