Coulomb Repulsion Strategy Synergizes Electronic Effects to Facilitate Efficient H2 Production from Alkaline Seawater

Abstract

Aiming at the two technical bottlenecks of severe chloride corrosion and sluggish reaction kinetics faced by seawater electrolysis for hydrogen (H2) production, this work utilizes a combination of coulomb repulsive interaction and electronic structure optimization to electrodeposit Bi-doped Ni-S nanoparticles on superhydrophilic/underwater superaerophobic properties Cu nanowire arrays (Bi,Ni-S/CuNW/CM). In situ Raman spectroscopy shows that sulphate-rich microenvironment can be constructed by sulfur species on the catalyst surface and a protective shield can be formed based on coulomb repulsion to protect the electrode from corrosion by chloride ions (Cl-) and hypochlorite ions (ClO-). Density functional theory (DFT) calculations further demonstrate that Bi doping leads to a downward shift of the d-band center (εd) of Ni, effectively weakening the overly strong adsorption of hydrogen intermediate (H*), thereby enhancing its catalytic activity. Furthermore, based on the unique design of nanowire array structure, not only the rapid desorption of bubbles on the catalyst surface can be accelerated, but also the cathodic salt deposition can be effectively prevented. Overall, this work combines the coulomb repulsion strategy with the electronic effect to provide a new method for H2 production via seawater electrolysis.

Keywords: electrolysis