Nanostructure Architectures of Tungsten Carbide for Methanol Electrooxidation Catalyst

作者:Jiang, Yekun; Shi, Meiqin*; Tong, Xue; Chu, Youqun; Ma, Chunan*
来源:Chinese Journal of Chemistry, 2016, 34(6): 624-630.
DOI:10.1002/cjoc.201500907

摘要

We reported a novel protocol to efficiently synthesize tungsten carbide (WC) nanomaterials with pure crystal structure and certain specific morphology. The key step in this protocol is the preparation of the catalyst precursor W18O49 with surface oxygen vacancies. The existence of large quantities of oxygen vacancies gives plenty channels for diffusion and keeps the specific morphology of WC in the carbonization process. Efforts to build WC blocks with well-defined geometrical shapes (e.g., rods, wires, spheres and flakes) have further expanded its possibility to be the support for methanol electrooxidation catalyst. The platinum supported on pure phase WC materials served as an effective CO tolerant electrocatalyst for methanol oxidation. Electrochemical experiments indicated that the improved catalytic activity was related to the special morphologies of WC supports. Its sea urchin like feature leads to substantial interfaces between WC and Pt by preparing more anchor points for Pt loading and also the barriers for the subsequent crystal growth, which enhances the synergistic effect between WC and Pt.