燃料电池中催化剂的稳定性是影响其实际应用的关键问题之一。本研究合成了锐钛矿型纺锤状TiO2纳米材料，并负载纳米Pt制备了TiO2-Pt双组分复合催化材料。将其制作成电极材料后，进行了TEM、XRD、拉曼光谱、电化学特性分析。结果表明：TiO2-Pt材料中Pt纳米颗粒的TEM形貌与TiO2的表面亲和力有关；该双组分催化剂呈现出两个单独的氧还原反应（ORR）峰；在负载Pt后，材料电荷传输电阻明显减小，使得TiO2-Pt中TiO2纺锤体组分上的ORR性能明显增强；紫外光可同时促进TiO2-Pt中两组分的ORR性能；TiO2-Pt比炭黑负载Pt具有更好的稳定性。
The long-term stability of the catalysts for fuel cell reactions is one of the obstacles that limit their practical application. Herein, anatase TiO2 nanospindles were synthesized as a support for the growth of Pt nanodots to obtain a TiO2-Pt catalyst for oxygen reduction reaction (ORR). TEM, XRD, Raman spectrum, and electrochemical testing were employed to characterize the properties of TiO2-Pt catalyst. Results showed as following: the morphology of Pt nanodots on TiO2-Pt catalyst was dependent on the surface affinity of TiO2 nanospindles; there were two individual ORR peaks of the dual-component catalyst; after Pt deposition, the ORR performance of the catalyst was enhanced, which was ascribed to the accelerated surface charge transport through the Pt nanodots; the oxygen reduction performance on both components of TiO2-Pt catalyst were promoted by ultraviolet light illumination; the long-term stability of TiO2-Pt nanospindle was better than that of commercial carbon black supported Pt catalyst.
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