碳载Pt-Cr合金催化剂的制备及其性能比较  

Preparation and characteristic of carbon-supported Pt-Cr alloy catalysts

作　　者：蔡庆华[1] 黄慧萍[1] 史玉芳[2] 张萍[1] 

机构地区：[1]中国地质大学材料科学与化学工程学院,湖北武汉430074 [2]中国地质大学地质过程与矿产资源国家重点实验室,湖北武汉430074

出　　处：《电源技术》2007年第10期782-785,共4页Chinese Journal of Power Sources

基　　金：国家自然科学基金资助项目(20576129)

摘　　要：用铬作掺杂元素,通过液相均相沉淀——气/固高温还原两段反应方法制备了碳载Pt-Cr合金催化剂,采用热分析方法(TG-DSC)、扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)技术测试了合金催化剂的晶体结构和表面形貌。结果表明,用VulcanXC-72作载体,N(Pt)∶N(Cr)为1∶1,热处理温度为950℃,催化剂的电化学活性表面积最大,催化活性最好。在电解液为0.5mol/dm3硫酸溶液和2mol/dm3甲醇/硫酸溶液中用循环伏安法测试,自制的碳载Pt-Cr合金催化剂比商业Pt/C催化剂甲醇氧化活性低,因为Cr的存在,降低了Pt活性点旁三个相邻Pt存在的概率,从而降低了甲醇的氧化活性。Carbon-supported Pt-Cr alloy catalysts were prepared by two-step reaction containing liquid depositing and gas-solid reducing. The physical property of the alloy catalysts was tested by TG and DSC, SEM and XRD techniques. The results show that when Vulcan XC-72 is used as carrier, the Pt ： Cr atomic ratio is 1 ： 1, and heat-temperature is 950℃, it has preferable catalytic characteristic and the largest electrochemical surface. In 0.5 mol/dm^3 H2SO4 and 2 mol/dm^3 CH3OH/H2SO4 solutions , alloy electrocatalysts are less active than the commertial Pt/C for methanol oxidation, this is attributed to its low activity for methanol oxidation due to the smaller probability for presenting three Pt neighboring Pt active site.

关 键 词：直接甲醇燃料电池:两步反应法 Pt—Cr/C催化剂 甲醇氧化 

分 类 号：TM911.4[电气工程—电力电子与电力传动]