双功能yolk-shell钴@钴氮碳掺杂氧电极催化剂  

York-shell Co@Co-N/C of bifunctional oxygen electrocatalysts

作　　者：水恒心 潘冯弘康 金田 胡军 刘洪来[1] SHUI Hengxin;PANFENG Hongkang;JIN Tian;HU Jun;LIU Honglai(State Key Laboratory of Chemical Engineering,East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]化学工程联合国家重点实验室,华东理工大学,上海200237

出　　处：《化工学报》2018年第11期4702-4712,共11页CIESC Journal

基　　金：国家重点基础研发计划项目(2015BAC04B01);国家自然科学基金项目(21676080,21878076)。

摘　　要：以ZIF-67为模板,通过表面原位聚合多巴胺,与金属Co^(2+)发生强烈螯合,释放出有机配体,得到中空的金属-有机结构材料(Co-PDA)。通过900℃高温处理得到类似蛋黄(yolk-shell)结构的金属氮掺杂碳材料(Co@CoN/C)。这种特殊结构的材料具有优异的氧还原(ORR)和析氧反应(OER)电催化活性,在0.1 mol/L KOH电解液中,其ORR的半波电位为0.81 V,Tafel斜率为60 mV/dec;在电流密度为10 m A/cm^2时,其OER过电位为390 mV,Tafel斜率为71 mV/dec,总的氧电极催化活性为0.82 V,是一种优良的双功能氧电极催化剂。ZIF-67 was used as a template for producing metal and nitrogen doped carbon composite as electrocatalysts.By an in-situ polymerization of dopamine on the surface of ZIF-67,Co2+ions were extracted into the polydopamine shell due to the strong chelation between them and led to the decomposition of ZIF-67,which resulted into a hollow composite of Co-PDA.Subsequently,a yolk-shell structure of metal and nitrogen doped carbon composites(Co@Co-N/C)was obtained by a high temperature pyrolysis at 900℃.The unique structure of Co@Co-N/C provided excellent bifunctional electrocatalysts for both oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),repetitively.For ORR,the half-wave potential was 0.81 V and the Tafel slope was 60 mV/dec.For OER,the overpotential was 390 mV at the current density of 10 mA/cm2,and the Tafel slope was 71 mV/dec.More importantly,the total oxygen electrocatalytic activity was as low as 0.82 V.

关 键 词：电化学 催化剂 纳米结构 钴氮碳掺杂氧电极 ZIF-67 

分 类 号：TQ028.8[化学工程]