物理化学学报 >> 2015, Vol. 31 >> Issue (5): 998-1006.doi: 10.3866/PKU.WHXB201503191

材料物理化学 上一篇    

碳化钨与蒙脱石纳米复合材料的制备与电催化活性

潘剑明1, 杨威2, 孙海标2, 郑翔2, 李国华2,3   

  1. 1 浙江省贵金属催化材料与技术重点实验室, 杭州310011;
    2 浙江工业大学化学工程学院, 杭州310014;
    3 浙江工业大学, 绿色化学合成技术国家重点实验室培训基地, 杭州310012
  • 收稿日期:2014-11-24 修回日期:2015-03-18 发布日期:2015-05-08
  • 通讯作者: 李国华 E-mail:nanozjut@zjut.edu.cn
  • 基金资助:

    国家自然科学基金(21173193, 213001154)及浙江省贵金属催化材料与技术重点实验室开放基金项目资助

Preparation and Electrocatalytic Activity of Tungsten Carbide-Montmorillonite Composite

PAN Jian-Ming1, YANG Wei2, SUN Hai-Biao2, ZHENG Xiang2, LI Guo-Hua2,3   

  1. 1 Key Laboratory of Noble Metal Catalytic Materials and Technology of Zhejiang Province, Hangzhou 310011, P. R. China;
    2 School of Chemical Engineering, Zhejiang University of Technology, Hangzhou 310014, P. R. China;
    3 State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology, Zhejiang University of Technology, Hangzhou 310032, P. R. China
  • Received:2014-11-24 Revised:2015-03-18 Published:2015-05-08
  • Contact: LI Guo-Hua E-mail:nanozjut@zjut.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21173193, 213001154) and Key Laboratory of Noble Metal Catalytic Materials and Technology of Zhejiang Province, China.

摘要:

具有类铂催化性能的碳化钨(WC)催化材料是当前研究的热点与难点. 本文以六氯化钨为钨源, 用剥离后的蒙脱石片层为载体, 将化学浸渍法与原位还原碳化法技术相结合制备了碳化钨与蒙脱石纳米复合材料; 复合材料由碳化钨、碳化二钨(W2C)和蒙脱石(MMT)组成, 碳化钨呈颗粒状分散或呈层状负载于MMT外表面; 样品的晶相组成与其还原碳化时间有关; 样品的微结构特征与前驱体中钨与蒙脱石的比例有关. 采用三电极体系和循环伏安法测试了样品在酸性溶液中对甲醇的电催化氧化性能, 结果表明, 碳化钨与蒙脱石复合之后对甲醇的电催化性能明显提升, 并具有类铂电催化活性; 当钨与蒙脱石质量比为4 的前驱体经5 h 还原碳化后, 样品中WC占绝对主导, WC和W2C的质量分数分别为82%和18%, 两者的比值为4.556, 且在MMT外表面形成均匀的负载层. 此时样品的电催化活性最高. 这为制备具有类铂催化活性的高性能碳化钨催化材料奠定了坚实基础.

关键词: 碳化钨, 蒙脱石, 纳米复合材料, 电催化活性, 类铂催化性能

Abstract:

The tungsten carbide catalyst is a hot research topic because its catalytic properties are similar to those of platinum. In this paper, a tungsten carbide-montmorillonite (MMT) nanocomposite was fabricated by combining chemical immersion with reduction and carbonization in situ using tungsten hexachloride as the tungsten source and an exfoliated MMT layer as the support. The crystal phase of the sample is composed of monotungsten carbide (WC), bitungsten carbide (W2C), and MMT, and tungsten carbide is distributed on the outer surface of MMT with a granular or lamellar manner. The components of the crystal phase of the sample are related to the reduction and carbonization time during preparation. The microstructure of the sample is related to the ratio of tungsten to MMT in the precursor used to prepare the sample. The electrocatalytic activity of the sample for methanol oxidation was measured by cyclic voltammetry with a three-electrode system in acidic solution. The results show that the electrocatalytic activity of the sample is improved by compositing tungsten carbide on the surface of MMT, and the electrocatalytic activity is similar to that of platinum. After 5 h reduction and carbonization, a precursor with a 4:1 ratio of tungsten to MMT transformed into a sample with 82%and 18% of WC and W2C, respectively (ratio of WC to W2C 4.556). The WC phase forms a uniform loaded layer on the surface of MMT. The electrocatalytic activity of this sample is the highest of the compositions considered. This outline a method to fabricate a tungsten carbide electrocatalyst with similar electrocatalytic activity to platinum.

Key words: Tungsten carbide, Montmorillonite, Nanocomposite, Electrocatalytic activity, Catalic property similarity of platinum

MSC2000: 

  • O643