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Transition metal and transition metal sulfides have been widely used as electrode materials in the field of energy storage and conversion. In this work, we fabricate uniform and compact NiCu film on the surface of nickel foam (NF) by a facile filtered cathodic vacuum arc technique (NiCu/NF). Then the electrode is sulfurized via electrochemical process (NiCu2S2/NF), which possesses abundant electroactive sites. Both the electrodes display good electrochemical performance in methanol electrooxidation and supercapacitors, simultaneously. NiCu2S2/NF electrode exhibits higher electrocatalytic activity of 825 mA mg−1 for methanol oxidation in KOH solution. In supercapacitors, NiCu2S2/NF electrode delivers a superior specific capacity of 1975.2 C g−1 at 0.5 mA cm−2 and better rate capability. NiCu2S2/NF electrode exhibits an improved electrochemical activity. Particularly, NiCu/NF electrode displays a higher cycle stability (76.8% retention) after 3000 cycles at 10 mA cm−2, owing to the stable adhesion of NiCu film. Hopefully, filtered cathodic vacuum arc technique can be applied to prepare binary transition metal, which can be simultaneously applied in fuel cells and supercapacitors.

In this work, a facile and unique electrode is fabricated by ion implantation and hydrothermal sulfurization methods for the first time. A spicules-like Ni3S2 shell is directly grown on the molybdenum nanoparticles doped nickel foam (MoNPs/NF@Ni3S2), which exhibits a special hierarchical structure. It is employed as the electrode of supercapacitor, exhibiting good electrochemical performance with high areal capacity of 1.06 C cm−2 (361 C g−1) at 1 mA cm−2, good rate capability, and long cycling life (168% of the initial capacity) for 7000 cycles at 20 mA cm−2. Compared with Ni3S2/NF, the electrode possesses better performance, which is attributed to the doped MoNPs, special morphology of Ni3S2, the hierarchical structure, as well as the synergistic effect between Ni3S2 and MoNPs. A symmetric supercapacitor based on MoNPs/NF@Ni3S2 electrodes maintains 108% of the original capacity after cycling for 7000 cycles at 0.5 mA cm−2. The results mean that MoNPs/NF@Ni3S2 could be used as a battery-type electrode for supercapacitors.