Facile synthesis of NiCo2S4@Ni3Se2 nanocomposites for supercapacitor and electrocatalytic H2 production

In this work, NiCo2S4@Ni3Se2 nanocomposites were fabricated with facile hydrothermal + electrodeposition method on Ni foam and the performances of energy storage and hydrogen evolution reaction were systematically investigated. As the electrode material for supercapacitor, NiCo2S4@Ni3Se2 demonstrated a specific capacitance of 9.82F cm-2 at 3 mA cm-2. The corresponding asymmetric supercapacitor exhibited the specific capacitance of 5.18F cm-2 at 3 mA cm-2 and retained 66.6% with current density increasing to 20 mA cm-2. Moreover, NiCo2S4@Ni3Se2-1.0-5 exhibited an outstanding electrocatalytic activation with low potential of 1.396 V for urea electrooxidation reaction (UOR) and 1.415 V for ethanol oxidation reaction (EOR) at current density of 10 mA cm-2 and the corresponding two-electrode overall water splitting potential reached at 1.566 V in 1 M KOH + 0.1 M urea. Thus, this study demonstrates the promising practical applications of NiCo2S4@Ni3Se2 nanocomposites for energy storage and hydrogen evolution reaction.