Co3Se4 nanosheets embedded on N-CNT as an efficient electroactive material for hydrogen evolution and supercapacitor applications

Abstract Co 3 Se 4 on nitrogen doped carbon nanotube (N-CNT) with applications for supercapacitor and hydrogen evolution reaction (HER) is synthesized by pyrolysis and solvothermal processes. The catalyst due to improved electrical conductivity and increased rate of removal of H 2 liberated, delivers a high HER activity, by reaching η 10 at 174 mV and 240 mV, Tafel slope of 73.2 and 43.8 mV dec −1 in alkaline and acidic medium respectively. Co 3 Se 4 /N-CNT as supercapacitor electrodes, yields a capacitance of 114 F g −1 at a 2 mV s −1 scan rate, with an excellent capacitive retention of 96% of the initial capacitance after 5000 cycles.