A highly-efficient oxygen evolution electrode based on defective nickel-iron layered double hydroxide  

基于富缺陷镍铁水滑石材料的高效析氧电极(英文)

作　　者：Xuya Xiong Zhao Cai Daojin Zhou Guoxin Zhang Qian Zhang Yin Jia Xinxuan Duan Qixian Xie Shibin Lai Tianhui Xie Yaping Li Xiaoming Sun Xue Duan 熊旭亚;蔡钊;周道金;张国新;张倩;贾茵;段欣旋;谢启贤;赖仕斌;谢添慧;李亚平;孙晓明;段雪(State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology;Department of Chemistry and Energy Sciences Institute, Yale University, 810 West Campus Drive;College of Electrical Engineering and Automation, Shandong University of Science and Technology;College of Energy, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology)

机构地区：[1]State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China [2]Department of Chemistry and Energy Sciences Institute, Yale University, 810 West Campus Drive, West Haven CT 06516, USA [3]College of Electrical Engineering and Automation, Shandong University of Science and Technology, Tsingtao 266590, China [4]College of Energy, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China

出　　处：《Science China Materials》2018年第7期939-947,共9页中国科学（材料科学（英文版）

基　　金：supported by the National Natural Science Foundation of China,National Key Research and Development Project (2016YFC0801302, 2016YFF0204402);the Program for Changjiang Scholars and Innovative Research Team in the University;the Fundamental Research Funds for the Central Universities;the longterm subsidy mechanism from the Ministry of Finance;the Ministry of Education of China

摘　　要：Exploring efficient and cost-effective electro- catalysts for oxygen evolution reaction （OER） is critical to water splitting. While nickel-iron layered double hydroxide （NiFe LDH） has been long recognized as a promising non- precious electrocatalyst for OER, its intrinsic activity needs further improvement. Herein, we design a highly-efficient oxygen evolution electrode based on defective NiFe LDH na- noarray. By combing the merits of the modulated electronic structure, more exposed active sites, and the conductive elec- trode, the defective NiFe LDH electrocatalysts show a low onset potential of 1.40 V （vs. RHE）. An overpotential of only 200 mV is required for 10 mA cm-2, which is 48 mV lower than that of pristine NiFe-LDH. Density functional theory plus U （DFT＋U） calculations are further employed for the origin of this OER activity enhancement. We find the introduction of oxygen vacancies leads to a lower valance state of Fe and the narrowed bandgap, which means the electrons tend to be ea- sily excited into the conduction band, resulting in the lowered reaction overpotential and enhanced OER performance.探索低成本高效率的析氧电极对于工业电解水技术的发展至关重要.尽管镍铁水滑石已被公认为是一种高效析氧的非贵金属催化剂,但其本征活性还有待进一步提高.本研究通过将氧空位缺陷引入镍铁水滑石,设计出一种低成本高效率的析氧电极.通过精确电子结构调控,暴露更多活性位点,提高电极导电性,富缺陷镍铁水滑石电极展现出1.40 V(vs.RHE)的低起峰电位.同时,它仅需200 m V过电势就能达到10 m A cm^(-2)的电流密度,这相比未经处理的镍铁水滑石降低了48 m V.我们进一步通过密度泛函理论计算发现,氧空位缺陷的引入使Fe的价态降低,带隙减小,使得催化过程中电子更容易被激发到导带中,从而降低反应过电势并使析氧活性增强.

关 键 词：oxygen evolution reaction layered double hydroxide oxygen vacancy ELECTROCATALYSIS 

分 类 号：O646.5[理学—物理化学] TQ116.2[理学—化学]