Heptanuclear brucite disk with cyanide bridges in a cocrystal and tracking its pyrolysis to an efficient oxygen evolution electrode

作     者：Jian-Qiang Zhao Dandan Cai Jun Dai Mohamedally Kurmoo Xu Peng Ming-Hua Zeng 

作者机构：Key Laboratory for the Chemistry and Molecular Engineering of Medicinal ResourcesDepartment of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China Hubei Collaborative Innovation Center for Advanced Organic Chemical MaterialsMinistry of Education Key Laboratory for the Synthesis and Application of Organic Functional MoleculesCollege of Chemistry and Chemical EngineeringHubei UniversityWuhan 430062China Institut de Chimie de StrasbourgCNRS-UMR7177Universite de Strasbourg67070 Strasbourg CedexFrance 

出 版 物：《Science Bulletin》 (科学通报（英文版）)

年 卷 期：2019年第64卷第22期

页      面：1667-1674页

核心收录：

学科分类：07[理学] 070304[理学-物理化学(含∶化学物理)] 0703[理学-化学] 

基　　金：supported by the National Natural Science Foundation of China for Distinguished Young Scholars (21525101) the BAGUI Talent Program and Scholar Program (2014A001) the National Natural Science Foundation of China (21805074 and 21661008) the Natural Science Foundation of Hubei Province (2017CFA006 and 2018CFB151) the Natural Science Foundation of Guangxi Zhuang Autonomous Region (2017GXNSFDA198040) supported by the Centre National de la Recherche Cientifique (CNRS, France) 

主　　题：Cobalt disk clusters Thermogravimetry-mass spectrometry Pyrolysis tracking Core-shell nanostructure Oxygen evolution reaction 

摘      要：The development of efficient oxygen evolution reaction(OER)catalysts is still lacking in exploration of the mechanism of controlled pyrolysis of precursors among new material platforms.Here,a novel Co-based coordination molecular cluster has been first introduced as precursor to obtain metallic cobalt core shelled by N-doped carbon(Co@NC)structure which operates as an oxygen evolution electrode.Specifically,a new cocrystal compound,[Co7II(l3-CN)6(mmimp)6][CoIICl3N(CN)2]á3CH3OH(Co7+1,mmimp=2-methoxy-6-((methylimino)-methyl)phenol),was isolated consisting of Brucite disks of cobalt where the usual bridging l3-OH is replaced by l3-CN produced by the in-situ decomposition of dicyanamide(NC-N-CNà).The cobalt atoms are bonded through the nitrogen atom of the cyanide.Remarkably,time dependent thermogravimetric-mass spectrometry(TG-MS)analysis was utilized to track its pyrolysis process.It allowed us to propose a possible formation process of the Co@NC structure from Co7+1.Interestingly,an extremely superior OER electrode is optimized for Co@NC-600 having the lowest overpotential of257 m V at 10 m A/cm2in 1 mol/L KOH solution.The present study pins down the importance of clusters of transition metals on realizing distinct nanostructures operating as highly efficient OER electrocatalyst.