Ni-/Fe-based materials are promising electrocatalysts for the oxygen evolution reaction (OER) but usually are not suitable for the hydrogen evolution reaction (HER). Herein, a durable and bifunctional catalyst consisting of Ni-FeO x and FeNi3 is prepared on nickel foam (Ni-FeO x /FeNi3/NF) by in situ solution combustion and subsequent calcination to accomplish efficient alkaline water splitting. Density functional theory (DFT) calculation shows that the high HER activity is attributed to the strong electronic coupling effects between FeO x and FeNi3 in the Janus nanoparticles by modulating ΔG H* and electronic states. Consequently, small overpotentials (η) of 71 and 272 mV in HER and 269 and 405 mV in OER yield current densities (j) of 50 and 1000 mA cm–2, respectively. The catalyst shows outstanding stability for 280 and 200 h in HER and OER at a j of ∼50 mA cm–2. Also, the robustness and mechanical stability of the electrode at an elevated j of ∼500 mA cm–2 are excellent. Moreover, Ni-FeO x /FeNi3/NF shows excellent water splitting activities as a bifunctional catalyst as exemplified by j of 50 and 500 mA cm–2 at cell voltages of 1.58 and 1.80 V, respectively. The Ni-FeO x /FeNi3/NF structure synthesized by the novel, simple, and scalable strategy has large potential in commercial water electrolysis, and the in situ combustion method holds great promise in the fabrication of thin-film electrodes for different applications.

The practicality of zinc-ion batteries (ZIBs) is compromise seriously because of the mutual restrictions of hydrogen evolution, by-product formation and zincdendrite growth. Herein, anhydrous gel polymer electrolytes (GPEs) with catalytic ions and in situdomain-constrained zinc ions are designed. Innovatively, copper ions are confined in the network structure of the gel for accelerating the deposition and migration kinetics of zinc ions. Not only does this anhydrous GPEs exhibit strong mechanicaland thermal properties, but it also presents a high ionic conductivity (24.32 mS cm −1 ) and a high zinc ion transference number (0.42). Consequently, the anhydrous GPEs is capable of stable cycling of symmetrical Zn cells at 1 mA cm −2 with acumulative capacity of 1000 mAh cm −2 and maintaines a high discharge specific capacity of 124.6 mAh g −1 after 1000 long-term cycles of the Zn-MnO 2 battery (ZMB) at 1 C. The synergistic catalytic strategy of composite gel opens new opportunities for a promising pathway to facilitate the large-scale application of ZIBs with hydrogel electrolytes.

The increasing demand for high performance portable electronic devices has promoted the research of flexible energy storage devices, and various devices have been suggested and investigated.

This paper investigated the preparation of 3D RGO/CdS hydrogels by a facile hydrothermal process, the morphology control of CdS (ball-like, rod-like, needle-like) in 3D structures, and their application in electrochemical energy storage.