PEDOT decorated CoNi2S4 nanosheets electrode as bifunctional electrocatalyst for enhanced electrocatalysis

Developing stable and highly efficient bifunctional electrocatalyst is very important for sustainable energy conversion technology. However, conventional electrocatalytic materials often show high overpotentials and low chemical activities. Conductive polymers anchored is thought an effective strategy to solve this problem. In this work, we report a kind of novel nanosheet arrays through a facile hydrothermal and subsequent electrodeposition process. The as-obtained CoNi2S4@PEDOT-150 products possess an overpotential of 270 mV for oxygen evolution reaction (OER) at 50 mA cm−2 and 90 mV for hydrogen evolution reaction (HER) at 10 mA cm−2 in 1.0 M KOH electrolyte. In addition, the electrode can be used as both anode and cathode for overall water splitting. It only requires a cell voltage of 1.75 V at 50 mA cm−2, which is superior to previous reports.