Bifunctional Fe-doped CoP@Ni2P heteroarchitectures for high-efficient water electrocatalysis

It is important to develop economical and durable electrocatalysts for sustainable energy conversion technology. However, the current catalysts still suffer from insufficient hydrogen adsorption energy. Herein, we report a kind of novel bi-phosphide catalyst through constructing heterogeneous structures and cation doping. The obtained sample delivers an outstanding hydrogen evolution reaction (HER) performance at all pH range. As oxygen evolution reaction (OER) electrocatalyst, Fe-CoP@Ni2P samples show an overpotential of 237 mV at 50 mA·cm−2 in alkaline solution. For electrolysis of water, Fe-CoP@Ni2P catalysts deliver a cell voltage of 1.59 V at 50 mA·cm−2 and long durability. Furthermore, density functional theory (DFT) calculation further confirms that the doped heterostructure promotes Gibbs free energy for hydrogen adsorption. And the significant increase in the density of total states (DOS) also enhances the catalytic activity of HER.