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The alkaline hydrogen evolution reaction (HER) of MoS2 is hampered by its sluggish water dissociation kinetics as well as limited edge sites. Herein, Ni3S2/MoS2 is fabricated as a model catalyst to highlight interfacial structural and electronic modulations of MoS2 for realizing its high performance in the alkaline HER. Experiments and density functional theory results demonstrate that the coupled Ni3S2 species can not only promote the adsorption and dissociation of H2O to boost the alkaline HER kinetics but also tailor the inert plane of MoS2 to create abundant unsaturated edge-like active sites, while the interfacial electron interaction can regulate the band gaps and Gibbs free energy of hydrogen adsorption of MoS2 to improve the electron conductivity as well as HER activity. Moreover, field emission scanning electron microscopy, transmission electron microscopy, Raman, ex situ synchrotron radiation X-ray absorption, and X-ray photoelectron spectroscopy results reveal the excellent structural stability of Ni3S2/MoS2 during the HER. As expected, the target Ni3S2/MoS2 achieves an ultralow overpotential of 68 mV at 10 mA cm–2, a fast alkaline HER kinetics, and remarkable durability. The proposed concept of interfacial structural and electronic reorganization could be extended to develop other functional materials.

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Biomass-derived activated carbon has attracted much attention in electrochemical energy systems, and its great potential can be further unlocked for achieving high-performance by tuning its composition and structure. Herein, we prepared activated carbon using wheat straw as the biomass feedstock. The oxygen functional groups and pore volume of the target activated carbon were successfully tuned using the mixed activator of potassium carbonate and potassium hydroxide. As a result, the activated carbon (named as AC-HC) displayed an excellent oxygen reduction reaction (ORR) behavior in terms of a small half-wave potential of 0.77 V and a large limiting current density, resulting in Zn−air batteries with a high trip efficiency of 60.7% and a long cycle life (280 h/1680 cycles).

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