Developing low-cost, efficient, and bifunctional electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is an appealing yet challenging task. Herein, for the first time, a NiS microsphere film was grown in situ on Ni foam (NiS/Ni foam) via a sulfurization reaction as an efficient bifunctional electrocatalyst for overall water splitting with superior activity and good durability. This NiS/Ni foam electrode delivers 20 mA cm(-2) at an overpotential of 158 mV for the HER and 50 mA cm(-2) at an overpotential of 335 mV for the OER in 1.0 M KOH. This bifunctional electrode also enables a high-efficiency alkaline water electrolyzer with 10 mA cm(-2) at a cell voltage of only 1.64 V, which could be promising in water splitting devices for large-scale hydrogen production.

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Developing low cost and efficient anode and cathode materials toward electrocatalysis are regarded as one of the most desirable yet challenging research directions, which are intimately related to the pressing energy, environmental and human health issues. Currently, 3 D foam (such as Ni foam, Cu foam, and graphene foam) based heterogeneous catalysts have been intensively explored for actively catalyzing the electrode reactions. Their inherent characteristics of stereo‐network structure, high specific area and large pore volume not only provide better mass transport of reactants to electrode surfaces, but also pave 3 D electron transport pathways. Herein, recent significant progress and rational design of foam‐based electrocatalysts are reviewed. In addition, some insights into current challenges and future directions of foams for efficient electrocatalysis are proposed and discussed.

Bimetallic iron–nickel sulfide nanowall arrays supported on nickel foam (Fe11.1%–Ni3S2/Ni foam) could efficiently drive both the overall water and urea electrolysis.

A prerequisite for exploiting most proposed applications for MoS2 is the availability of water-dispersible functionalized MoS2 nanosheets in large quantities. Here we report one-step synthesis and surface functionalization of MoS2 nanosheets by a facile ionic liquid assisted grinding method in the presence of chitosan. The selected ionic liquid with suitable surface energy could efficiently overcome the van der Waals force between the MoS2 layers. Meanwhile, chitosan molecules bind to the plane of MoS2 sheets non-covalently, which prevents the reassembling of exfoliated MoS2 sheets and facilitates the exfoliation progress. The obtained chitosan functionalized MoS2 nanosheets possess favorable stability and biocompatibility, which renders them as promising and biocompatible near-infrared agents for photothermal ablation of cancer. This contribution provides a facile way for the green, one-step and large-scale synthesis of advanced functional MoS2 materials.