CoPy/C催化剂应用碱性介质氧还原催化的电化学性能(英文)  

Electrocatalytic Activity of CoPy/C Catalyst for the Oxygen Reduction Reaction in Alkaline Electrolyte

作　　者：徐莉[1] 乔锦丽[1] 丁蕾[1] 胡隆宇[1] 刘玲玲[1] 王海江 

机构地区：[1]东华大学环境科学与工程学院,上海201620 [2]加拿大国家研究院,燃料电池创新研究所,温哥华V6T1W5

出　　处：《物理化学学报》2011年第10期2251-2254,共4页Acta Physico-Chimica Sinica

基　　金：supported by the National Natural Science Foundation of China(21173039);Pujiang Foundation of Shanghai,China(08PJ14096);Natural Science Foundation of Shanghai Science and Technology Committee,China(09ZR1433300);Opening Foundation of Zhejing Provincial Top Key Discipline,China(20110927);Scientific Research Foundation for the Returned Overseas Chinese Scholars,Ministry of Education of China(2009(1001));Shanghai Leading Academic Discipline Project Fund,China(B604)~~

摘　　要：利用碳黑(Vulcan XC-72R)中加入硫酸钴和吡啶(Py)作为催化剂前驱体,经溶剂分散热处理构建了一类新型的高效氧还原CoPy/C复合催化剂.并运用循环伏安法(CV)和旋转圆盘电极(RDE)技术研究了不同Co含量的CoPy/C催化剂在碱性介质中对氧还原的电催化活性.结果表明:Co的存在对氧的催化剂活性位的形成有重要影响,800℃下所制备的10%Co30%Py/C(质量分数)复合催化剂表现出最佳的氧还原催化活性.以其制备的气体扩散电极在3.0 mol·L^(-1)KOH电解质溶液(O_2气氛)中0.014 V(相对于标准氧电极(RHE))即可产生明显的氧还原电流.同40%Py/C相比,10%Co30%Py/C催化氧还原的起峰电位正移了71 mV,同时表现出明显的极限扩散电流.在-0.16 V时电流密度达到最大值,电流密度为1.0 mA·cm^(-2),半波电位在-0.07 V.透射电镜分析表明所制备的碳黑载吡啶钴(10%Co30%Py/C)催化剂平均粒径为20 nm.In this communication, we report a novel CoPy/C catalyst for the oxygen reduction reaction （ORR） in alkaline electrolyte using cobalt sulfate heptahydrate （COSO4 · 7H2O） and pyridine （Py） as the Co and N precursors supported on Vulcan XC-72R, followed by heat treatment in an inert atmosphere. Electrochemical performances were evaluated using cyclic voltammograms （CVs） and rotating disk electrode （RDE） technique in terms of its ORR activity as a function of Co content in the catalyst synthesis. Results show that the presence of Co in the CoPy/C catalyst greatly affects the formation of ORR catalytic active sites and that the best performing catalyst is 10%Co%30Py/C, which was synthesized at 800℃. In 3.0 mol. L-1 KOH, 10%Co30%Py/C （in 02） produces an obvious ORR current with an on-set potential at 0.014 V. Compared with the 40% Py/C the on-set potential of the 10% Co30% Py/C for oxygen reduction shifted positively by 71 mV （versus RHE （reversible hydrogen electrode）） and a well-defined limiting current plateau was achieved. Therefore, a maximum current density of 1.0 mA· cm-2 was obtained at-0.16 V with a half-wave potential of-0.07 V. Transmission electron microscopy （TEM） measurements show that the nanoparticles with a diameter of 20 nm are uniformly dispersed on Vulcan carbon （Vulcan XC-72R）.

关 键 词：碱性燃料电池:CoPy/C 热处理:氧还原反应:循环伏安:旋转圆盘电极 

分 类 号：O646.54[理学—物理化学]