摘要：制备一种具有高氧还原电催化活性的Pt-TiO₂-还原氧化石墨烯复合材料;采用X射线衍射、扫描电镜、透射电镜、高分辨透射电镜和拉曼光谱分析手段对催化剂的组成和微观结构进行表征。结果表明:氧化石墨烯在复合材料的合成过程中被还原为还原氧化石墨烯,纳米Pt与TiO₂颗粒均匀地附着在还原氧化石墨烯的片层上形成Pt-TiO₂-还原氧化石墨烯复合材料;该复合材料氧还原起始电位为-0.20 V左右,通过Koutecky-Levich方程计算得到电催化过程中复合材料的交换电流密度为10^-6~10^-5m A/cm²,16 000 s的计时电流测试后其相对电流值高达起始值的88%以上。

关键词：二氧化钛;氧化石墨烯;纳米复合材料;氧还原反应

Abstract： Pt -TiO₂ -reduced graphene oxide composite materials with high oxygen reduction catalytic activity were prepared. Composition and structure of the composite materials were characterized by XRD， SEM， TEM， HRTEM and RM. The results show that the graphene oxide is reduced， and Pt and TiO₂ nano-particles are evenly distributed on the reduced graphene oxide to form Pt -TiO₂ -reduced graphene oxide composite materials. The onset potential of oxygen reduction under the Pt-TiO₂-reduced graphene oxide composite materials is about -0.20 V， the exchange current density obtained by Koutecky-Levich theory is 10^-6~10^-5m A/cm². The current still remains more than 88% of their initial after chronoamperometric test for 16 000 s. 

Keywords: titania； graphene oxide； nano-composite materials； oxygen reduction reaction