Lattice oxygen activation enabled by high-valence metal sites for enhanced water oxidation

Abstract Anodic oxygen evolution reaction (OER) is recognized as kinetic bottleneck in water electrolysis. Transition metal sites with high valence states can accelerate the reaction kinetics to offer highly intrinsic activity, but suffer from thermodynamic formation barrier. Here, we show subtle engineering of highly oxidized Ni 4+ species in surface reconstructed (oxy)hydroxides on multicomponent FeCoCrNi alloy film through interatomically electronic interplay. Our spectroscopic investigations with theoretical studies uncover that Fe component enables the formation of Ni 4+ species, which is energetically favored by the multistep evolution of Ni 2+ →Ni 3+ →Ni 4+ . The dynamically constructed Ni 4+ species…

• CU
  City University of Hong Kong

  Award: 9610461
• NN
  National Natural Science Foundation of China

  Award: 51801075
• HK
  Hong Kong Polytechnic University

  Awards: JCYJ20180507183424383, N_PolyU540/17, G-YW2A
• NS
  National Synchrotron Radiation Laboratory
• SM
  Shenzhen Municipal Science and Technology Innovation Council