直接乙醇燃料电池阳极催化剂Pt-Rh-SnO2/C的制备与表征

用交替微波法制备了SnO2/C复合材料,以该材料为载体制备了不同Pt∶Rh比例的Pt-Rh-SnO2/C催化剂,应用透射电镜（TEM）及X射线衍射（XRD）方法对所制备催化剂的微观结构进行了表征,通过循环伏安法和计时电流法测试了催化剂对乙醇的催化氧化性能.结果表明,微波辅助多元醇法利用SnO2/C作为催化剂载体可以制备具有良好分散度的Pt-Rh-SnO2/C催化剂,不同比例的Pt-Rh-SnO2/C催化剂金属粒子的平均粒径都小于4nm,且粒径分布较窄;该系列催化剂中Pt具有面心立方结构,随着Pt含量不断增加,粒径逐渐增加.当Pt∶Rh比例为3∶1时,对乙醇的催化氧化具有最好的稳定性和活性.

Preparation and Characterization of Pt-Rh-SnO2/C for Direct Ethanol Fuel Cell

SnO2/C composites were prepared by an intermittent microwave in heating method and used as the support to prepare Pt-Rh-SnO2/C with different Pt∶Rh atomic ratio.The results of X-ray diffraction（XRD）and transmission electron microscopy（TEM）measurements show that the as-prepared catalysts were composed of well-dispersed Pt-Rh-SnO2 nanoparticles with an average particle size less than 4 nm.All the as-prepared catalysts have face-centred cubic（fcc）crystalline structure.With an increase of Pt∶Rh molar ratio,the particle sizes are increasing.Electrochemical studies are carried out using cyclic voltammetry and chronoamperometry.The results show that the highest electrocatalytic activity and the best stability for ethanol electro-oxidation were obtained at Pt∶Rh molar ratio with 3∶1.