Ultralow Ru-assisted and Vanadium-doped Flower-like CoP/Ni2P Heterostructure for Efficient Water Splitting in Alkali and Seawater

High cost performance catalysts are urgently required for hydrogen production from electrochemical water electrolysis by the hydrogen evolution reaction (HER) and slow oxygen evolution reaction (OER). Herein, by means of phosphating CoV-LDH impregnated with Ru (Ru-CoV-LDH/NF), a Vanadium (V)-doped flower-like CoP/Ni2P heterostructure coupled with ultralow Ru (RuV-CoNiP/NF) is constructed. The electronic modulation caused by V doping effectively stimulates the activity of the CoP /Ni2P heterostructure assisted with ultrasmall Ru nanoparticles, thus the formed RuV-CoNiP/NF effectively drives the HER (η10=28 mV) and OER (η20=214 mV) in alkaline media. Impressively, during the overall water decomposition, it requires only an overpotential of 1.469V to achieve 10 mA cm-2, demonstrating almost the most remarkable catalytic performance compared to the past literature. Notably, the catalyst can still positively promote the electrolysis of alkaline seawater: when achieving 20 mA cm-2, the required overpotential is only 1.538 V, which is almost the best experimental result at present. This work provides an idea for achieving high cost performance bifunctional catalysts toward hydrogen production from water and seawater splitting.