【作者】 陈冬梅； 王平渊； 曾珣； 孙艳芝； 朱必学； 潘军青；

【Author】 Dongmei CHEN;Pingyuan WANG;Xun Zeng;Yanzhi SUN;Bixue ZHU;Junqing PAN;Key Laboratory of Macrocyclic and Supramolecular Chemistry,Guizhou University;State Key Laboratory of Chemical Resource Engineering,Beijing University of Chemical Technology;

【机构】 贵州大学大环及超分子化学重点实验室； 北京化工大学化工资源有效利用国家重点实验室；

【摘要】 燃料电池（Fuel Cells）是通过电化学机制将化学能直接转化成电能的装置,具有清洁、高效的特点。相对于氢的阳极氧化反应（HOR）过程来说,氧的阴极还原（ORR）过程的反应速度较阳极反应速率小6-7个数量级,导致阴极过电位更高,相应的阴极催化剂中Pt等贵金属的用量更大^[1,2],因此开发新型高效非贵金属氧还原阴极催化剂已成为这一领域的研究热点。本文采用共沉淀法制备出宽度为20 nm左右,长度为200 nm左右的Ag₄Bi₂O₅棒状晶体,样品的XRD和SEM如图1所示。图2为该催化剂的RDE测试。从图可以看出,样品在氧气氛中显示了较强的氧还原电流,并在考察电位下i^-1与转速ω^-1/2呈很好的线性关系,在-0.8^-0.9 V之间的电子转移数分别为4.3、4.2和4.4,说明Ag₄Bi₂O₅催化还原氧气是按四电子反应历程进行的,同时部分铋酸银在阴极过程也参与了协同还原反应,使得电子转移数略高于4。更多还原

【Abstract】 Nano Ag₄Bi₂O₅ is synthesized by co-precipitation method. The XRD and SEM results show the Ag₄Bi₂O₅ is a nano rod crystal with about 20 nm in width and 200 nm in length. The RDE tests show the sample-has good electro-catalytic activity, and the electron transfer number is 4.3, 4.2and 4.4, respectively. The -i^{-1 ω-1/2} plots present a good linear relationship which indicating Ag₄Bi₂O₅ catalytic is carried by the four-electron reaction mechanism during the ORR process, with the scanning potential ranging from-0.8V to-0.9 V. The results also reveal that the Ag₄Bi₂O₅ is involved in the co-reduction reaction, so the electron transfer number is slightly higher than 4.更多还原