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The electrolyte‐wettability at electrode material/electrolyte interface is a critical factor that governs the fundamental mechanisms of electrochemical reaction efficiency and kinetics of electrode materials in practical electrochemical energy storage. Therefore, the design and construction of electrode material surfaces with improved electrolyte‐wettability has been demonstrated to be important to optimize electrochemical energy storage performance of electrode material. Here, we comprehensively summarize advanced strategies and key progresses in surface chemical modification for enhancing electrolyte‐wettability of electrode materials, including polar atom doping by post treatment, introducing functional groups, grafting molecular brushes, and surface coating by in situ reaction. Specifically, the basic principles, characteristics, and challenges of these surface chemical strategies for improving electrolyte‐wettability of electrode materials are discussed in detail. Finally, the potential research directions regarding the surface chemical strategies and advanced characterization techniques for electrolyte‐wettability in the future are provided. This review not only insights into the surface chemical strategies for improving electrolyte‐wettability of electrode materials, but also provides strategic guidance for the electrolyte‐wettability modification and optimization of electrode materials in pursuing high‐performance electrochemical energy storage devices. [ABSTRACT FROM AUTHOR]

Photorechargeable zinc ion batteries (PZIBs), which can directly harvest and store solar energy, are promising technologies for the development of a renewable energy society. However, the incompatibility requirement between narrow band gap and wide coverage has raised severe challenges for high‐efficiency dual‐functional photocathodes. Herein, half‐metallic vanadium (III) oxide (V2O3) was first reported as a dual‐functional photocathode for PZIBs. Theoretical and experimental results revealed its unique photoelectrical and zinc ion storage properties for capturing and storing solar energy. To this end, a synergistic protective etching strategy was developed to construct carbon superstructure‐supported V2O3 nanospheres (V2O3@CSs). The half‐metallic characteristics of V2O3, combined with the three‐dimensional superstructure assembled by ultrathin carbon nanosheets, established rapid charge transfer networks and robust framework for efficient and stable solar‐energy storage. Consequently, the V2O3@CSs photocathode delivered record zinc ion storage properties, including a photo‐assisted discharge capacities of 463 mA ⋅ h ⋅ g−1 at 2.0 A ⋅ g−1 and long‐term cycling stability over 3000 cycles. Notably, the PZIBs assembled using V2O3@CSs photocathodes could be photorecharged without an external circuit, exhibiting a high photo conversion efficiency (0.354 %) and photorecharge voltage (1.0 V). This study offered a promising direction for the direct capture and storage of solar energy. [ABSTRACT FROM AUTHOR]

As an emerging high-power density energy storage device, supercapacitors are limited in their development by electrode materials. Transition metal nitrides have attracted widespread attention in supercapacitors due to their high electrical conductivity and considerable capacity. Among them, vanadium nitride features a high theoretical capacity and excellent electrical conductivity, nevertheless, its solubility problem in alkaline electrolytes has always hindered the practical application of vanadium nitride. Herein, a universal method is reported for the preparation of vanadium nitride quantum dot composites by solvothermal methods and in situ substitution. Using the stable ZIF-8 dodecahedral structure, vanadium ions are riveted to the structure of the metal–organic framework by in situ substitution; after high-temperature annealing, it retains the dodecahedral structure of ZIF-8 and forms hollow nanocages. This hollow structure generates more active sites and ameliorates the reaction kinetics of the vanadium nitride material. It has a capacity of 278 F g−1 at a current density of 0.5 A g−1. Interestingly, a capacity retention rate of 82.23% can be achieved after 20 000 cycles at a current density of 3 A g−1. In addition, the assembled device exhibits a coulombic efficiency of 97.35%, a power density of 775 W Kg−1, and an energy density of 49.8 W h kg−1. This good electrochemical performance, especially the enhanced cycling stability, should be attributed to the effective solution to solve the dissolution problem of vanadium nitride in electrolytes. In conclusion, the proposed method is simple and easy to implement and has a broad utilization value and application prospects in energy conversion and storage systems. [ABSTRACT FROM AUTHOR]

This paper focuses on the sharing and compatibility studies of International Mobile Telecommunications 2020 (IMT-2020) and inter-satellite service (ISS) in 26 GHz frequency band, which was selected by International Telecommunications Union (ITU) as one of the most promising candidate frequency bands for 5G. Based on relevant ITU recommendations and reports, and current technical characteristics of both systems, a methodology is developed for the interference coexistence analysis between them. The spatial and temporal distribution analysis is proposed and the calculation of IMT-2020 aggregate interference takes the actual urban population into consideration. The results show that these two systems have considerable possibilities in coexistence in 26 GHz frequency band.