Bifunctional Hybrid Ni/Ni2P Nanoparticles Encapsulated by Graphitic Carbon Supported with N, S Modified 3D Carbon Framework for Highly Efficient Overall Water Splitting

Abstract The novel hybrid Ni/Ni 2 P nanoparticles with graphitic carbon coating supported by 3D N, S dual modified binder‐free macroporous carbon framework (Ni/Ni 2 P@3DNSC) are reported as an efficient bifunctional electrocatalysts for the production of hydrogen and oxygen. The obtained Ni/Ni 2 P@3DNSC electrode exhibits an excellent catalytic activity with a low overpotential of 231 mV for oxygen evolution reaction (OER) and 92 mV for hydrogen evolution reaction (HER) due to the strong coupled interface of Ni and Ni 2 P, synergistic effects between the hybrid Ni/Ni 2 P core and the graphitic carbon shell, the unique porous structure, and the heteroatoms doped effect. When both are used as cathode and anode, only a low cell voltage of 1.55 V is needed to achieve the current density of 10 mA cm −2 . This work demonstrates a new avenue for the development of bifunctional nonprecious electrocatalysts for the sustainable energy utilization.