WxC/GC的离子交换-碳化制备及其载铂电化学性能

WxC/GC synthesized By an Ion-exchange Carbonaization method and its Electrochemical Performance

摘要:

本文以离子交换树脂为碳源，偏钨酸铵（AMT）为钨源和亚铁氰化钾（K4Fe(CN)6·3H2O）为催化剂，采用离子交换法制备树脂基前躯体，在氮气气氛下高温还原同步碳化制备碳化钨/石墨碳（WxC/GC）复合物。以WxC/GC为载体，采用微波加热乙二醇还原法负载纳米铂（Pt）颗粒制备了Pt/WxC/GC催化剂。通过XRD、TG和SEM等测试技术分析了WxC/GC的形成过程及其形貌。并在酸性介质中测试Pt/WxC/GC的电催化性能。实验结果表明：制备的WxC/GC复合物颗粒细小，分散均匀，WxC粒径为2-30 nm左右。载质量分数10%Pt的Pt/WxC/GC在酸性介质中具有较好的电催化活性和稳定性，对甲醇的氧化电流密度峰值为39 mA·cm-2。

Abstract:

A simple approach was proposed to fabricate tungsten carbides/graphitic carbon（WxC/GC） composites by using ion-exchange resin as carbon resource，ammonium metatungstate(AMT) as tungsten source and the potassium ferrocyanide（K4Fe(CN)6·3H2O）as catalyst. The resin-based precursor was prepared via the ion-exchange method and underwent reduction and synchronous carbonization at high temperature under N2 atmosphere to fabricate WxC/GC composites. Furthermore, the WxC/GC supported platinum nanoparticle (Pt/WxC/GC) was prepared by microwave-assisted polyol method. The crystalline phase，structure and morphology of samples were characterized with X—ray diffraction(XRD)，transmission electronic microscope(TEM)，and energy dispersive X-ray spectroscopy(EDS)．The electro-catalytic activity of Pt/WxC/GC in acidic media was investigated using cyclic voltammetry. The results indicated that WxC particles were uniformly distributed in the as-synthesized WxC/GC composites with the size of 2～30nm. Pt/WxC/GC with 10wt% Pt exhibits attractive catalytic activity and stability, the oxidation current density of methanol can reach 39mA·cm-2.