热处理温度对钴卟啉负载碳黑电催化剂的结构及氧还原性能的影响  

Effect of Heated-treating Temperature on the Electrocatalysis of Oxygen Reduction for Carbon Black-supported CoTMPP/BP2000

作　　者：王爱琴[1] 任奇志[1] 刘双艳[1] 麻晓霞[1] 谢先宇[1] 

机构地区：[1]上海交通大学化学化工学院,上海200240

出　　处：《高等学校化学学报》2009年第4期752-756,共5页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:20871082;20471037和20776085);上海市自然科学基金(批准号:03ZR14061)资助

摘　　要：制备了钴卟啉负载碳黑催化剂（CoTMPP／BP2000）用于燃料电池阴极氧还原反应．利用循环伏安法研究了200～900℃热处理温度对催化性能的影响．研究结果表明，热处理能够提高CoTMPP／BP2000的催化活性，热处理温度为900℃时，催化剂的氧还原能力最好．利用紫外-可见光谱、透射电镜、红外光谱、热重分析及X射线光电子能谱等手段研究了热处理温度对催化剂结构的影响．结果表明，热处理改变了催化剂的活性中心结构，400℃以上热处理使催化剂中钴卟啉环的结构坍塌，Co—N4键断裂；900℃高温下形成了稳定的Co-Nx-C结构，新的活性位使催化剂的氧还原能力得到提高．Carbon black-supported cobalt tetramethoxyphenylporphyrin CoTMPP/BP2000 was prepared as cathode electrocatalyst for the oxygen reduction in proton exchange membrane fuel cell（PEMFC）. The effect of various heated-treating temperature from 200 ℃ to 900 ℃ on the electroeatalytie activities for oxygen reduction of CoTMPP/BP2000 were investigated by cyclic vohammogram（CV） and Koutecky-Levich plot. Results show that the heat-treatment can enhance the catalytrie activity and stability of the catalyst, 900 ℃ is found to be the most suitable temperature. The influence of heate-treating temperature of CoTMPP/BP2000 was analyzed by UV-Vis, TEM, IR, TG and XPS methods. Results reveal that heated-treatment can change the central structure of catalyst, the porphyrin ring and Co-N4 band of the catalyst can not exited with and after 400 ℃ heattreatment. The most stable Co-Nx-C structure was formed with 900 ℃ heat-treatment, this new active site can efficiently improve the catalytic ability of oxygen reduction of CoTMPP/BP2000.

关 键 词：热处理 钴卟啉负载碳黑催化剂 循环伏安 氧还原 燃料电池 

分 类 号：O643[理学—物理化学] O614[理学—化学]