Novel BDD-loaded bimetallic phosphide electrodes enable interesting bifunctional seawater electrolysis.

The direct electrolysis of seawater for the production of green hydrogen energy is an economically attractive approach. However, this technique confronts technical problems because to the oxygen evolution reaction (OER) weak stability and inadequate selectivity due to competition with the chlorine evolution process. This work focuses on improving the stability of the electrode and electrolysis efficiency. The phosphating NiCoP active layer with 3D porous morphology was created by electrodeposition on the B-doped diamond (BDD) as an electrode inspired by the bifunctional catalysis strategy. The successfully constructed unique cube-on-nanosheets structure in the NiCoP active layer enables the electrode to exhibit excellent electrocatalytic performance. The porous NiCoP/BDD (Por-NiCoP/BDD) electrodes showed good catalytic activity in alkaline-simulated seawater with the OER and hydrogen evolution reaction (HER) overpotentials of 400 and 261 mV, respectively, at a current density of 100 mA cm−2. More importantly, the electrode exhibits interesting stability of the catalytic performance and structural in alkaline-simulated seawater electrolysis, with the current density decaying by only 1.52 % and 4.06 % after OER and HER processes for 50 h, respectively. This work expands the valuable application scenarios of BDD electrode and provides novel ideas for the development of seawater electrolysis. [Display omitted] • The controllable preparation of Por-NiCoP/BDD electrodes with 3D porous morphology was achieved. • The constructed NiCoP catalytic layer presents an interesting cauliflower-like structure. • The Por-NiCoP/BDD electrodes exhibit interesting bifunctional catalytic performance (OER and HER). • The Por-NiCoP/BDD electrodes exhibited attractive structural stability in alkaline-simulated seawater. [ABSTRACT FROM AUTHOR]