协同Ni_(3)N/Ni异质结构核和超薄Ni_(3)N表面壳实现自适应的表面重构和高效析氧  

Synergizing In-grown Ni_(3)N/Ni Heterostructured Core and Realizing Self-adaptive Surface Reconfiguration and Efficient Oxygen Evolution Reaction on Ultrathin Ni_(3)N Surface Shell

作　　者：高晓蕊 刘西蒙 董慧龙 庞亚俊 寇宗魁 王鹏颜 潘争辉 魏孙睿 木士春[4] 王家功 GAO Xiaorui;LIU Ximeng;DONG Huilong;PANG Yajun;KOU Zongkui;WANG Pengyan;PANG Zhenghui;WEI Sunrui;MU Shichun;WANG Jiagong(School of Electronic and Information Engineering,Changshu Institute of Technology,Changshu 215500,China;School of Materials Engineering,Changshu Institute of Technology,Changshu 215500,China;Department of Materials Science and Engineering,National University of Singapore,117574 Singapore,Singapore;State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070;College of Physics and Optoelectronic Engineering,Shenzhen University,Shenzhen 518060,China)

机构地区：[1]常熟理工学院电子信息工程学院,江苏常熟215500 [2]常熟理工学院材料工程学院,江苏常熟215500 [3]新加坡国立大学材料科学与工程系,新加坡117574 [4]武汉理工大学材料复合新技术国家重点实验室,武汉430070 [5]深圳大学物理与光电学院,深圳518060

出　　处：《常熟理工学院学报》2021年第2期18-20,共3页Journal of Changshu Institute of Technology

基　　金：国家留学基金委访问学者项目(201808320091)。

摘　　要：寻找高活性、碱性稳定且具有极低过电位的非贵金属基析氧反应(OER)催化剂有巨大的价值,但由于OER缓慢的动力学,使其商业化面临相当大的挑战.本文中,我们通过一种自适应的表面重构方法设计了一种强耦合核壳纳米结构的预催化剂.该预催化剂由内部生长的Ni_(3)N/Ni异质结构核和超薄Ni_(3)N壳(Ni_(3)N/Ni@Ni_(3)N)组成,通过逐步的热氮化路径合成.Ni_(3)N/Ni@Ni_(3)N样品在电流密度10 mA·cm^(-2)下展现出超低的过电位(229 mV),其在过电位270 mV下,电流密度为单独的Ni_(3)N、Ni以及商业RuO_(2)催化剂的17,37和20倍,同时具有较低的塔菲尔斜率(55 mV·dec^(-1)).在OER过程中,Ni_(3)N/Ni@Ni_(3)N样品的表面发生了重构,生成了高活性的NiOOH.原位拉曼光谱和非原位电子显微镜的研究证实了这一点.密度泛函理论(DFT)计算结果表明,NiOOH到Ni_(3)N的界面电子转移产生了带正电的Ni阳离子,大大降低了OER中间产物吸附/脱附的能垒.Searching for highly active,alkaline-stable and low-cost non-noble metal-based oxygen evolution reaction(OER)catalysts with disruptively low overpotential and outstanding overall performance is of great value and yet faces considerable challenge,due to the sluggish OER kinetics reported for almost all known materials systems.To accelerate the sluggish OER kinetics by a self-adaptive surface reconfiguration approach,we have purposely designed a strongly coupled core@shell nanostructured precatalyst consisting of an in-grown Ni3N/Ni heterostructured core and an ultrathin Ni3N shell(Ni3N/Ni@Ni3N)via a step-by-step thermal nitridation route.The Ni3N/Ni@Ni3N thus-obtained delivers an ultralow overpotential(η)of 229 mV at 10 mA·cm-2,with the remarkable 17-,37-and 20-fold enhancements in catalytic current density per active surface area atη=270 mV,compared favorably to the individual Ni3N and Ni alone as well as the commercial RuO2,respectively,together with a much reduced Tafel slope of 55 mV dec-1.A self-adaptive surface reconfiguration in Ni3N/Ni@Ni3N takes place,by forming highly active NiOOH during the OER process.It is confirmed by the studies of both the in-situ Raman spectrometry and ex-situ electron microscopy.The density functional theory(DFT)calculations demonstrate that the interfacial electron transfer from NiOOH to Ni3N produces positive-charged Ni cations as the highly active sites to substantially lower the energy barriers for adsorption/desorption of the OER intermediates.

关 键 词：Ni3N/Ni@Ni3N 核壳结构 析氧反应 表面重构 

分 类 号：O643.36[理学—物理化学]