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Accelerating the kinetics of the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is vital for high-efficiency green hydrogen production. However, developing cost-effective and highly active bifunctional catalysts for overall water splitting electrolysis remains a huge challenge. Herein, the CuNi/CoFe LDH heterostructure is synthesized in situ on nickel foam (CuNi/CoFe LDH@NF) by a simple two-step electrodeposition process. The synergy of the CuNi alloy and CoFe LDH optimizes the electron distribution at the interface and improves the intrinsic activity of the HER/OER. Consequently, the optimal CuNi/CoFe LDH@NF bifunctional catalyst displays low overpotentials of 56 mV (10 mA cm−2) and 268 mV (50 mA cm−2) for the HER and OER, respectively, along with high stability in alkaline electrolyte. Remarkably, CuNi/CoFe LDH@NF as the cathode and anode requires a low voltage (1.49 V) to achieve 10 mA cm−2 for overall water splitting. Meanwhile, it also displays favorable stability for operation for 17 h (50 mA cm−2) without obvious decline of the cell voltage. Density functional theory calculations indicate that constructing heterojunction interfaces promotes the redistribution of interface electrons and optimizes the free energy of adsorbed intermediates, thereby reducing the energy barrier of the rate-determining step (from *O to *OOH). [ABSTRACT FROM AUTHOR]

By constructing a Ag2O/Bi4O5I2 p–n heterojunction and applying a heat-localization microreactor, efficient photocatalysis enhanced by both photoinduced carrier separation and the photothermal effect was realized. This work focuses on the utilization of near-infrared light to broaden the absorption spectrum and accelerate the transportation of carriers. Through the production and localization of heat, it provides a novel thought for full-spectrum photocatalysis. [ABSTRACT FROM AUTHOR]

Hydrogen (H2) is a new type of renewable energy that can meet people's growing energy needs and is environmentally friendly. In order to improve the industrial application prospects and electrochemical performance of hydrogen evolution catalysts, extensive research on transition metal materials has been carried out. Among the many catalytic materials, cobalt is an element with potential for the hydrogen evolution reaction (HER) due to its abundant reserves, low cost, and small energy barrier for H adsorption. This review classifies the latest research on cobalt-based catalysts according to the types of compound, including cobalt-based sulfides, phosphides, carbides, borides, oxides, etc., and summarizes the latest research progress of cobalt-based compound catalysts in acidic and alkaline media. Strategies to tune the properties of cobalt-based compound catalysts for high catalytic activity for HER are focused on, including structural engineering, defect engineering, and doping, etc. The advantages and limitations of each modified approach are reviewed. Not only that, but also the catalytic activity and advantages of the catalyst are evaluated by using density functional theory (DFT) calculation-related descriptors, activity evaluation parameters, etc. Finally, limitations and challenges of cobalt-based materials for HER are presented, as well as prospects for future research. This paper aims to understand the chemical and physical factors that affect cobalt-based catalysts, and to find directions for future research on cobalt-based catalysts. [ABSTRACT FROM AUTHOR]

The design and development of composite materials with novel structures is one of the effective ways to enhance the electrochemical properties of supercapacitors. In this paper, a one-step electrodeposition method is used to adjust the morphology and structure of CoMnS nanomaterials by changing the amount of CS2. CoMnS nanomaterials with unique flower-like structures are reasonably prepared, which promotes the flow of electron transfer and improves the electrochemical behavior. It is worth noting that when the amount of CS2 is 4 mmol, the specific capacitance of CoMnS-4 reaches 3469.5 F g−1 at 1 A g−1, and the specific capacitance is still 2830.5 F g−1 (maintaining 81.56%) until the high current density reaches 20 A g−1. After 10 000 cycles, it shows excellent cycle stability (maintaining 95.78% at 20 A g−1). The CoMnS-4//AC asymmetric supercapacitor device has an excellent energy density of 85.91 W h kg−1 when the power density is 800 W kg−1, which shows it's great application value. [ABSTRACT FROM AUTHOR]

To develop responsive organogels, a low molecular mass gelator (Chol-Se) with selenium as its redox-active center was designed and synthesized. Chol-Se could form thermally reversible physical gels in several organic solvents. By controlling the redox state of the selenide group in Chol-Se, responsive transformation of Chol-Se in ethyl acetate between the gelation and solution was achieved. Chol-Se will serve as an excellent smart material with potential applications in sensors, recognition, and separation. [ABSTRACT FROM AUTHOR]