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

The novel hybrid Ni/Ni2P nanoparticles with graphitic carbon coating supported by 3D N, S dual modified binder-free macroporous carbon framework (Ni/Ni2P@3DNSC) are reported as an efficient bifunctional electrocatalysts for the production of hydrogen and oxygen. The obtained Ni/Ni2P@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 Ni2P, synergistic effects between the hybrid Ni/Ni2P 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.