Manipulating electronic structure of nickel phosphide via asymmetric coordination interaction for anion-exchange membrane based seawater electrolysis

Alkaline seawater electrolysis faces serious problems such as low catalytic activity of bifunctional catalysts and vulnerability to Cl - corrosion. Hence, Ru-doped nickel phosphide asymmetric structure (Ru-Ni 2 P/Ni 5 P 4 ) has been synthesized as highly efficient and corrosion resistant electrocatalysts for alkaline seawater electrolysis at high current density. In -situ characterization technique and DFT calculations reveal that compared with the monophase nickel phosphide, the construction of Ni x P asymmetric structure manipulate the electronic structure and dband center, promoting the adsorption of intermediates, as well as accelerate phase transition of the OER process. Moreover, the weak adsorption energy of Cl - on the surface of the Ru-Ni 2 P/Ni 5 P 4 catalyst avoids the corrosion of Cl - in seawater. Consequently, Ru-Ni 2 P/Ni 5 P 4 achieve 1000 mA cm -2 with overpotentials of only 128 and 450 mV for HER and OER, respectively. After assembling the Anion -exchange -membrane water electrolyzer (AEMWE), Ru-Ni 2 P/Ni 5 P 4 shows high average efficiency and economic value at different current densities, and demonstrates its corrosion resistance to Cl - and potential for industrial applications.