Synergistic insights into the electrocatalytic mechanisms of ZIF-derived Co3S4 on 1T-WS2/WO3 for electrochemical water splitting

Abstract

Designing a highly effective bifunctional electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is a sensible approach for generating enormous hydrogen fuel by electrochemical water splitting. Herein, a high performance of ZIF-derived Co₃S₄ on WS₂-WO₃ electrocatalyst was developed for overall water splitting reactions. For developing the mixed phase of WS₂-WO₃, thioacetamide (TAA) played a crucial role as a sulfur source and acted as intercalating agent for expanding the layers of 1T WS₂ via the possible generation of NH₄⁺ ion. The high electrocatalytic performances is attained by the homogeneous incorporation and tunable properties of nano-sized Co₃S₄ on WS₂-WO₃. The electrocatalyst showed remarkable HER performance with an overpotential of only 73 mV and good OER efficiency with an overpotential of 307 mV at 10 mA/cm². The long term chronopotentiometry and CV cycles performances convinces the stability of the electrocatalysts. A reasonable two-electrode overall water splitting performance was achieved by the WS₂-WO₃/Co₃S₄ electrocatalyst in an asymmetric device, paving the path for more developments in the design and optimization of electrocatalysts for renewable energy conversion.