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Electrocatalysts for hydrogen evolution made from earth’s rich elements are key to a sustainable and clean hydrogen economy. Now, using a straightforward way to make valid catalysts with preferable catalytic activity from inexpensive raw materials in large scale remains challenge. The preparation of nickel-sulfur hybrid nanoplate electrocatalyst has a deep consideration because of its ordinary preparation process, outstanding property, and fine stabilization. In this work, employing an improved chemical vapor deposition (CVD) synthesis method to fabricate a highly efficient and stable NiS2/NiS electrocatalyst prepared by changing the mass of nickel-sulfur ratios of 8:1 (NiS2/NiS-8), 4:1 (NiS2/NiS-4), 2:1 (NiS2/NiS-2), and 1:1 (NiS2/NiS-1), applied to hydrogen evolution reactions (HER). The acquired NiS2/NiS-4 showed excellent HER performance with an overpotential of 202 mV to drive 100 mA/cm2 in 1 M KOH solution with a Tafel slope of 69.0 mV/dec, also with 30 h stability testing. This vigorous catalyst, fabricated from commercial Ni foam, has a potential for industrialization of hydrogen economy and will stimulate the industrial development of nonprecious metal catalyst.

Ammonium vanadate (NH4V3O8) materials have attracted considerable attention due to their low cost, high discharge capacity, and simple synthesis process. However, the further application of NH4V3O8 materials as cathode for lithium-ion batteries is hindered by the low electronic conductivity and lithium-ion diffusion coefficient. Herein, intersperse Super P nanoparticles between NH4V3O8 microsheets to increase the Li+ diffusion coefficient of NH4V3O8 electrodes. Compared with pure NH4V3O8, the cycling stability of NH4V3O8/Super P composites improved obviously. At a current density of 15 mA g−1 after 200 cycles, the reversible capacity of composites (110 mAh g−1) is much higher than the pure NH4V3O8 (70 mAh g−1). Besides, the composites exhibit excellent rate capability, and the reversible capacity achieves 66 mAh g−1 at a high current density of 300 mA g−1. The excellent electrochemical performance is mainly attributed to the addition of Super P carbon black nanoparticles, which increases the conductivity and the Li+ diffusion coefficient.