Porous Oxygen-doped NiCoP Nanoneedles for High Performance Hybrid Supercapacitor

Abstract The preparation of electrode materials with high performance is of great significance to the practical application of supercapacitors. Here, O-doped NiCoP (O-NiCoP) electrode material with porous nanoneedle structure was synthesized in-situ on carbon cloth by hydrothermal process and subsequent phosphorization treatment with high mass loading of 5.07 mg cm−2. The electrode combined the large specific surface area of porous nanoneedle, the high electronic conductivity of phosphide and the electronic structure regulation of oxygen element, which finally showed excellent electrochemical performance. The optimized O-NiCoP electrode delivered a high specific area capacity of 3457 mC cm−2 at a current density of 1 mA cm−2 and a high specific mass capacity of 621 C g−1 at a current density of 1 A g−1. The hybrid supercapacitor composed of O-NiCoP positive electrode and commercial activated carbon negative electrode exhibited a high energy density of 30.52 Wh kg−1 at a power density of 749.36 W kg−1.