One-Pot Synthesis of W2C/WS2 Hybrid Nanostructures for Improved Hydrogen Evolution Reactions and Supercapacitors

Abstract

Tungsten sulfide (WS₂) and tungsten carbide (W₂C) are materialized as the auspicious candidates for various electrochemical applications, owing to their plentiful active edge sites and better conductivity. In this work, the integration of W₂C and WS₂ was performed by using a simple chemical reaction to form W₂C/WS₂ hybrid as a proficient electrode for hydrogen evolution and supercapacitors. For the first time, a W₂C/WS₂ hybrid was engaged as a supercapacitor electrode and explored an incredible specific capacitance of ~1018 F g^-1 at 1 A g^-1 with the outstanding robustness. Furthermore, the constructed symmetric supercapacitor using W₂C/WS₂ possessed an energy density of 45.5 Wh kg^-1 at 0.5 kW kg^-1 power density. For hydrogen evolution, the W₂C/WS₂ hybrid produced the low overpotentials of 133 and 105 mV at 10 mA cm^-2 with the small Tafel slopes of 70 and 84 mV dec^-1 in acidic and alkaline media, respectively, proving their outstanding interfaced electrocatalytic characteristics. The engineered W₂C/WS₂-based electrode offered the high-performance for electrochemical energy applications.