Modulation of the electronic structure of CoP by surface and interface codoping boosts electrocatalytic oxygen evolution reaction

It is of great significance to develop economical, stable and abundant non-precious metal OER catalysts to replace the precious metal for the application and generalization of electrocatalytic overall water splitting technology. Herein, advanced Ni-doped CoP encapsulated by B, N co-doped carbon (Ni-CoP/BNC) electrocatalysts were prepared by using simple hydrothermal synthesis and calcination. The optimized Ni-CoP/BNC showed exhibits OER electrocatalytic performance with only need 247 mV to achieve 10 mA cm-2, outperforming the commercial RuO2. Combining various characterizations and DFT calculations, the excellent electrocatalytic performance mainly comes from three aspects: (1) Ni doped into CoP can significantly regulate the electronic structure of Co3+, and B doped into carbon layer can slightly regulate the electronic structure of Co3+, so that the electronic structure of Co3+ can be accurately regulated, resulting in the optimal OOH* adsorption energy; (2) Ni and B can be favor in oxidizing Co0 to Co3+, which is beneficial to persistently provide a catalytic active center for oxygen evolution reaction; (3) the B, N codoped carbon layer can effectively reduce the damage of strong alkali solution to the catalytic active center as armor. This work opens up fresh opportunities in the accurate regulation of electronic structure by surface and interface double doping for efficient oxygen evolution in water applications.