Cobalt–manganese sulfide hybridized Fe-doped 1T-Vanadium disulfide 3D-Hierarchical core-shell nanorods for extreme low potential overall water-splitting

Abstract

The cobalt manganese sulfide [CoMnS2] hybridized with Fe-doped (1T)-phase vanadium disulfide [VS2] 3D-hierarchical core-shell nanorods arrays electrocatalyst on nickel foam [NF] (CoMnS2@1T-Fe-VS2@NF) has been fabricated for overall water-splitting in the present study. The CoMnS2@1T-Fe-VS2@NF performs superior activities through the interface engineering between 1D cobalt manganese sulfide (CoMnS2) core and Fe-doped metallic (1T)-phase VS2 (1T-Fe-VS2) shell due to the modulation of surface electronic structure, hence, leading to enhancement of the intrinsic conductivity of the whole core-shell structure. The CoMnS2@1T-Fe-VS2@NF having plentiful heterointerfaces, requires a low overpotential of 89 mV to deliver 10 mA/cm2- for hydrogen evolution reaction (HER) and 260 mV to deliver 20 mA/cm2- for oxygen evolution reaction (OER). The CoMnS2@1T-Fe-VS2@NF (+, -) alkaline electrolyzer requires a low cell voltage of 1.51 V at 10 mA/cm2- for overall water splitting and demonstrates outstanding long-term stability during hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) over 30 h of continuous operation. The outstanding performance of CoMnS2@1T-Fe-VS2@NF can be ascribed to the synergistic catalysis of CoMnS2 core with the activated basal planes and edge sites of 1T-Fe-VS2 shell.