Oxygen　evolution　reaction　(OER)　is　one　of　the　most　important　components　of　various　electrochemical　systems　such　as　water　splitting,　metal　air　batteries,　and　carbon　dioxide　reduction.　However,　the　four-electron　process　of　OER　suffers　from　intrinsically　sluggish　kinetics,　which　contributes　to　significant　overpotential　in　the　electrochemical　system.　Herein,　highly　defective　NiFeV　layered　triple　hydroxide　(LTH)　catalyst　was　efficiently　prepared　using　a　one-step　hydrothermal　method.　The　crystal　structure,　electronic　structure,　and　surface　composition　of　NiFeV　LTH　were　characterized　by　X-ray　diffraction　and　photoelectron　spectroscopy.　Moreover,　NiFeV　LTH　demonstrated　a　superior　OER　catalytic　performance　with-low　overpotential　(158　mV　@10　mA·cm-2),　related　small　Tafel　slope　(102.3　mV·dec−1),　and　long-term　stability　at　a　high　current　density　of　100　mA·cm-2.　In　situ　Raman　spectroscopy　was　applied　to　investigate　the　surface　reconstruction　during　the　OER　process.　It　is　revealed　that　Ni　species　were　the　most　active　sites　at　low　overpotential,　with　the　potential　increasing　subsequently　Fe　and　V　gradually　participates　in　the　catalytic　reaction,　the　Fe　and　Ni　species　as　OER　catalytic　active　sites　lead　to　the　excellent　OER　catalytic　activity　of　NiFeV　LTH,　and　inhibited　the　further　dissolution　of　high-valence　NiOOH　at　high　overpotential.　The　mechanism　induced　the　outstanding　activity　and　stability　at　high　current　densities　in　NiFeV　LTH　system.　Dissolution　of　vanadium　excited　the　active　sites　of　NiFeV　LTH　synthesized　by　hydrothermal　method　which　promoted　both　activity　and　stability,　while　the　changes　of　surface　species　at　different　OER　potentials　were　detected　by　in　situ　Raman　spectroscopy.　Copyright　©　2024　Li,　Xu,　Wang,　Yan,　Feng　and　Li.