Binary FeNi phosphides dispersed on N,P-doped carbon nanosheets for highly efficient overall water splitting and rechargeable Zn-air batteries

Hybridization of non-precious metals with advanced carbon monolith provides a promising approach to substitute noble metal catalysts for various electrochemical reactions. The structural and electronic properties of non-precious metals significantly affect electrocatalytic performance, which depends on the physicochemical structure of carbon substrates and the types of metal components. Herein, binary FeNi phosphide nanoparticles coupled with N,P-modified carbon nanosheets were fabricated through an universal carbonization-phosphorization approach. Besides the structural advantage of 2D nanosheets, the electronic structure change of bimetallic FeNi phosphides via modulating Fe/Ni ratio is another reason responded for the exceptional activities with reduced overpotentials of this hybridized catalyst for both hydrogen evolution, oxygen evolution and oxygen reduction reactions. Furthermore, by employing the fabricated materials as electrode catalysts for overall water splitting and rechargeable Zn-air batteries with liquid and solid-state electrolytes, excellent performances are achieved in these energy conversion and storage devices, revealing the significant feasibility for practical applications.