Tungsten carbide-reduced graphene oxide intercalation compound as co-catalyst for methanol oxidation

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• 作者：Meiqin Shi ; Wentian Zhang ; Yingying Li ; Youqun Chu ; Chun'an Ma ; ^{science@zjut.edu.cn}
• 关键词：Tungsten carbide-reduced graphene oxide ; Intercalation compound ; Thiourea ; Anchoring ; Methanol oxidation
• 刊名：Chinese Journal of Catalysis
• 出版年：2016
• 出版时间：November 2016
• 年：2016
• 卷：37
• 期：11
• 页码：1851-1859
• 全文大小：1052 K
• 卷排序：37

文摘

Highly dispersed tungsten carbide (WC) nanoparticles (NPs) sandwiched between few-layer reduced graphene oxide (RGO) have been successfully synthesized by using thiourea as an anchoring and inducing reagent. The metatungstate ion, [H2W12O40]6−, is assembled on thiourea-modified graphene oxide (GO) by an impregnation method. The WC NPs, with a mean diameter of 1.5 nm, are obtained through a process whereby ammonium metatungstate first turns to WS2, which then forms an intercalation compound with RGO before growing, in situ, to WC NPs. The Pt/WC-RGO electrocatalysts are fabricated by a microwave-assisted method. The intimate contacts between Pt, WC, and RGO are confirmed by X-ray diffraction, scanning electron microscope, transmission electron microscope, and Raman spectroscopy. For methanol oxidation, the Pt/WC-RGO electrocatalyst exhibited an electrochemical surface area value of 246.1 m2/g Pt and a peak current density of 1364.7 mA/mg Pt, which are, respectively, 3.66 and 4.77 times greater than those of commercial Pt/C electrocatalyst (67.2 m2/g Pt, 286.0 mA/mg Pt). The excellent CO-poisoning resistance and long-term stability of the electrocatalyst are also evidenced by CO stripping, chronoamperometry, and accelerated durability testing. Because Pt/WC-RGO has higher catalytic activity compared with that of commercial Pt/C, as a result of its intercalated structure and synergistic effect, less Pt will be required for the same performance, which in turn will reduce the cost of the fuel cell. The present method is facile, efficient, and scalable for mass production of the nanomaterials.