Vertically aligned Ni/NiO nanocomposites with abundant oxygen deficient hetero-interfaces for enhanced overall water splitting

作     者：Hongxia Wang Meiyan Cui Gaoliang Fu Jiaye Zhang Xingyu Ding Irene Azaceta Matthew Bugnet Demie M.Kepaptsoglou Vlado K.Lazarov Victor Ade la Peña O’Shea Freddy E.Oropeza Kelvin H.L.Zhang 

作者机构：State Key Laboratory of Physical Chemistry of Solid SurfacesCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key Laboratory of Structural ChemistryFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Henan Provincial Key Laboratory of Nanocomposites and ApplicationsInstitute of Nanostructured Functional MaterialsHuanghe Science and Technology CollegeZhengzhou 450006China Department of PhysicsUniversity of YorkHeslingtonYorkYO105DDUK SuperSTEM LaboratorySciTech Daresbury CampusDaresbury WA44ADUK School of Chemical and Process EngineeringUniveristy of LeedsLeeds LS29JTUK Univ LyonCNRSINSA LyonUCBLMATEISUMR 551069621 VilleurbanneFrance Photoactivated Processes UnitIMDEA Energy InstituteParque Tecnológico de MóstolesAvda.Ramón de la Sagra 328935 MóstolesMadridSpain 

出 版 物：《Science China Chemistry》 (中国科学（化学英文版）)

年 卷 期：2022年第65卷第10期

页      面：1885-1894页

核心收录：

学科分类：081702[工学-化学工艺] 081705[工学-工业催化] 08[工学] 0817[工学-化学工程与技术] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：the National Natural Science Foundation of China(21872116) F.E.Oropeza and V.A.de la Peña O’Shea are grateful for the funding supported by the EU(ERC CoG HyMAP 648319)and Spanish AEI(NyMPhA PID2019-106315RB-I00) Also,this work has been funded by the regional government of Comunidad de Madrid and European Structural Funds through their financial support to FotoArt-CM project(S2018/NMT-4367) Besides,Fundación Ramon Areces funded this work though ArtLeaf project.Kelvin H.L.Zhang also acknowledge the Sino-German Mobility Program(M-0377) SuperSTEM is the National Research Facility for Advanced Electron Microscopy,funded from the Engineering and Physics Research Council(EPSRC) M.Bugnet is grateful to the SuperSTEM Laboratory for microscope access,and to the School of Chemical and Process Engineering at the University of Leeds for a visiting associate professorship and financial support 

主　　题：water splitting hydrogen evolution reaction electronic structure heterostructure vertically aligned nanocomposites 

摘      要：The design of heterostructured transition metal-based electrocatalysts with controlled composition and interfaces is key to increasing the efficiency of the water electrolysis and the elucidation of reaction *** this work,we report the synthesis of well-controlled vertically aligned Ni/NiO nanocomposites consisting of Ni nanoclusters embedded in NiO,which result in highly efficient electrocatalysts for overall water *** show that such a high catalytic efficiency toward both the hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER)originates from a synergetic effect at Ni/NiO interfaces that significantly reduces the energy barrier for water dissociation,and favours the formation of reactive H*intermediates on the Ni side of the interface,and OH_(ads) on the NiO side of the interface.A study of water chemisorption based on near-ambient pressure photoelectron spectroscopy indicates that the abundant hetero-interfaces in Ni/NiO nanocomposite promote the dissociation of water with a three-fold increase in the surface concentration of OH_(ads) compared with pure *** functional theory calculations indicate that Ni/NiO interface leads to the reduction of the water dissociation energy barrier due to a high concentration of oxygen vacancies at NiO side of the interface,whereas the formation of highly active metallic Ni sites with an optimal value of Gibbs free energy of H*(ΔG_(H*)=−0.16 eV)owes to a favourable adjustment of the electron energetics at the interface,thus accelerating the overall electrochemical water splitting.