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We report the direct growth of metallic Co9S8 nanosheets on carbon cloth (CC), which can serve as efficient binder-free electrocatalysts for the HER in neutral media.

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Design and synthesis of efficient noble metal-free hydrogen evolution catalysts is of paramount importance to the practical application of water-splitting devices. Herein, we report a novel synthetic method to grow dispersed molybdenum carbide (Mo2C) micro-islands on flexible carbon cloth (CC). This method involves controlled synthesis of a supramolecular hybrid between cetyltrimethyl ammonium cations and molybdate anions on CC, followed by simple thermal treatment of this supramolecular hybrid in Ar to form Mo2C on CC in situ. In this synthesis, the presence of cetyltrimethyl ammonium bromide is proven to be important because it effectively immobilizes molybdate ions on CC on the one hand and functions as a carbon source for the formation of Mo2C on the other. Moreover, the as-prepared Mo2C/CC composite material can serve as efficient binder-free cathode toward the hydrogen evolution reaction (HER). The Mo2C/CC affords a current density of 10 mA/cm 2 at a low overpotential of 140 mV and works stably in acid media with a Faraday yield of ~ 100%. The isolated island architecture of Mo2C ensures rich active sites to be exposed and allows the easy interaction of reactants (e.g., protons) with the active sites. Also, the strong adhesion between Mo2C and carbon cloth facilities electron transport/transfer in the composite material and is helpful for the achievement of excellent catalytic stability.

The development of earth‐abundant water oxidation electrocatalysts with high activity and durability is very important for many renewable energy conversion/storage processes. Herein, we report a facile synthetic method for the preparation of amorphous nickel–iron oxide/carbon composite nanofibers with high electrocatalytic activity and stability for the oxygen evolution reaction (OER). This method involves two main steps: (i) the electrospinning synthesis of Ni‐ and Fe‐embedded polyvinylpyrrolidone (PVP) polymer nanofibers as the precursor and (ii) the thermal conversion of this precursor in air at 250 °C into nickel–iron oxide/carbon composite nanofibers. Moreover, we show that the as‐obtained composite material exhibits a comparable catalytic activity and a superior catalytic stability to IrOx/C and RuOx, which are state‐of‐the‐art noble‐metal‐based water oxidation electrocatalysts. In particular, the obtained amorphous nickel–iron oxide/carbon composite nanofibers with an optimal Ni/Fe molar ratio of 1:2 afford a small overpotential of 310 mV at a current density of 10 mA cm−2, show high catalytic stability for >15 h, and give >90 % Faradaic yield toward the OER. The efficient catalytic activity of the material can be attributed to its overall conducive structural features for the OER, mainly including the amorphous phase structure of nickel–iron oxide, tunable Ni/Fe atomic ratio, and strongly coupled interaction between nickel–iron oxide and nanocarbon.

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This review summarizes the construction of nanostructured solid-state metal alkoxides and their conversion into functional inorganic nanomaterials.

Using earth abundant transition metal-based compounds to replace noble metal catalysts towards hydrogen evolution from water splitting seems to have great importance worldwide.