Oxygen defect-rich double-layer hierarchical porous Co3O4 arrays as high-efficient oxygen evolution catalyst for overall water splitting  

作　　者：Puxuan Yan Meilin Huang Benzhi Wang Zixia Wan Mancai Qian Hu Yan Tayirjan Taylor Isimjan Jianniao Tian Xiulin Yang 

机构地区：[1]Guangxi Key Laboratory of Low Carbon Energy Materials,School of Chemistry and Pharmaceutical Sciences,Guangxi Normal University,Guilin 541004,Guangxi,China [2]School of Material Science and Engineering,Guilin University of Electronic Technology,Guilin 541004,Guangxi,China [3]Saudi Arabia Basic Industries Corporation(SABIC)at King Abdullah University of Science and Technology(KAUST),Thuwal 23955-6900,Saudi Arabia

出　　处：《Journal of Energy Chemistry》2020年第8期299-306,I0011,共9页能源化学（英文版）

基　　金：supported by the National Natural Science Foundation of China (no.21965005);Natural Science Foundation of Guangxi Province (2018GXNSFAA294077, 2018GXNSFAA281220);Project of High-Level Talents of Guangxi (FKA18015, 2018ZD004);Innovation Project of Guangxi Graduate Education (XYCSZ2019056, YCBZ2019031)。

摘　　要：Construction of oxygen evolution electrocatalysts with abundant oxygen defects and large specific surface areas can significantly improve the conversion efficiency of overall water splitting.Herein,we adopt a controlled method to prepare oxygen defect-rich double-layer hierarchical porous Co3O4 arrays on nickel foam(DL-Co3O4/NF)for water splitting.The unique array-like structure,crystallinity,porosity,and chemical states have been carefully investigated through SEM,TEM,XRD,BET,and XPS techniques.The designated DL-Co3O4/NF has oxygen defects of up to 67.7%and a large BET surface area(57.4 m2g-1).Electrochemical studies show that the catalyst only requires an overpotential of 256 mV to reach 20 mA cm-2,as well as a small Tafel slope of 60.8 mV dec-1,which is far better than all control catalysts.Besides,the catalyst also demonstrates excellent overall water splitting performance in a two-electrode system and good long-term stability,far superior to most previously reported catalysts.Electrocatalytic mechanisms indicate that abundant oxygen vacancies provide more active sites and good conductivity.At the same time,the unique porous arrays facilitate electrolyte transport and gas emissions,thereby synergistically improving OER catalytic performance.

关 键 词：Metal-organic frameworks Array-like structure Oxygen defects Oxygen evolution Water splitting 

分 类 号：TQ116.2[化学工程—无机化工] TQ426