Deepening surface reconstruction on anodized nickel mesh boosts oxygen evolution under industrial alkaline conditions

Although the active species induced by surface reconstruction have been extensively studied during oxygen evolution reaction (OER), it is still highly challenging to regulate and promote the reconstruction level to achieve exceptional catalytic activity and stability for realistic alkaline water electrolysis (AWE). Herein, we demonstrated that nickel mesh (NM) treated by a facile electrochemical anodization (ANM) can be easily induced into a deep reconstruction level on surface after activation, attributing to the autologous creation of a porous and amorphous NiOx (OH)y layer. Additionally, the reconstruction level can be promoted by increasing the temperature and alkali concentration of the electrolyte during the activation process. The deeply reconstructed ANM enables excellent OER performance with a low overpotential of 284 mV to achieve 10 mA/cm2, 132 mV lower than that of the NM. When combined with a Raney Ni cathode, the assembled AWE device working under industrial conditions can implement 400 mA/cm2 current at a low cell voltage of 1.79 V with a stable operation for 14 days, showing great potential in practical hydrogen production.