水滑石前体法制备CoAl₂O₄/石墨烯气凝胶作为双功能电催化  

CoAl2O4/Graphene Aerogel by Hydrotalcite Precursor Method as Bifunctional Electrocatalysts

作　　者：张聪 孟格 

机构地区：[1]北京化工大学化工资源有效利用国家重点实验室,北京

出　　处：《物理化学进展》2017年第3期113-120,共8页Journal of Advances in Physical Chemistry

摘　　要：研究氧还原(ORR)和氧析出(OER)反应的双功能电催化剂,对于新能源电池的探索和应用有着重要意义。本文利用水滑石前驱体法水热合成了钴铝水滑石/石墨烯气凝胶(CoAl-LDH/GA),再经过高温煅烧过程,得到钴铝氧化物/石墨烯气凝胶(CoAl2O4/GA)。采用SEM、TEM以及XRD对材料的表面特征及微观结构进行了表征,并考察了该电极材料的电化学性能。结果表明,CoAl2O4/GA复合材料具有双功能电催化特性,在碱性电解质中其对OER和ORR都具有优异的催化活性。CoAl2O4/GA对ORR的催化活性可与商业Pt/C (20 wt%)相媲美,且循环稳定性远高于后者,同时其对OER的循环稳定性也优于商业Ir/C (20wt%)。Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are critical paired reac-tions for both energy conversion and storage. Recently, the research on electrocatalysts for OER/ ORR has been focused on the study of easy, cost-effective, and highly active composites as potential alternatives to the precious metal materials (such as Pt, Ru, Ir). In this work, cobalt-aluminum hydrotalcite/graphene aerogels (CoAl-LDH/GA) were fabricated via a facile hydrothermal process, using the electrostatic interaction of single cobalt aluminum hydrotalcite (CoAl-LDH) and graphene oxide (GO). After high temperature calcination process, the cobalt aluminum oxide/gra- phene aerogel composites (CoAl2O4/GA) were obtained. The surface properties, microstructure pore size, element content and crystalline phase of the prepared products had been characterized by means of SEM, TEM and XRD, respectively. Results showed that the best catalyst exhibited high activity, which was close to commercial Pt/C and Ir/C catalysts, while the cycle stability was much higher than the commercial one. Therefore, the CoAl2O4/GA composite material was a perfect bifunctional electrocatalyst materials.

关 键 词：钴铝水滑石 钴铝氧化物 石墨烯气凝胶 ORR/OER双功能催化剂 

分 类 号：O64[理学—物理化学]