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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]

Designing and optimizing the pore structure of porous carbon electrodes is essential for diverse energy storage systems. In this study, an innovative approach spray phase‐inversion strategy was developed for the rapid and efficient fabrication of controlled porous carbon aerogel. Moreover, the aggregation structure of polyacrylonitrile is controlled by adjusting the Hansen's solubility parameter, thereby regulating the electrode material structure. Furthermore, the theoretical analysis of the spray phase‐inversion process revealed that this regulation process is jointly regulated by solvent hydrodynamic diameter and phase‐inversion kinetics. Through optimization, a novel porous carbon material was obtained that exhibited excellent performance as an electrode material. When utilized in supercapacitors for energy storage, it demonstrated a high specific capacitance of 373.1 F g−1 in a 6 M KOH electrolyte solution. Simultaneously, it has been observed that the preparation strategy for porous electrodes offers notable advantages in terms of excellent designability, broad universality, simplicity, and high efficiency, thereby holding promise for large‐scale fabrication of diverse porous electrode materials and various types of electrodes for diverse energy storage applications. [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]

Zinc metal batteries are expected to be the next generation of energy storage devices due to their high safety, but their application is hampered by irreversible hydrogen evolution reaction and surface side reactions of zinc anodes. Here, a zwitterionic hydrogel electrolyte is reported based on polymerization of acrylamide and 1-(3-Sulfopropyl)-2-Vinylpyridinium betaine, and it exhibits the following advantages: the sulfonic acid group of 1-(3-Sulfopropyl)-2-Vinylpyridinium betaine can be preferentially adsorbed on metal Zinc to avoid side reactions and refine the affinity at the zinc-electrolyte interface; and the coordination of the negatively charged sulfonic acid group with Zn2+ alters the solvation structure of Zn2+, which further improves the restriction ability of side reactions. Consequently, Zn||Zn symmetric batteries can be stabilized for 1, 200 h of plating stripping at 1 mA cm−2. Zn||Cu batteries exhibit an impressive average coulombic efficiency of 99.8 % over a remarkable span of 1, 800 cycles at a current density of 15 mA cm−2. Furthermore, the Zn||MnO 2 /Carbon nanotube batteries have been cycled more than 2, 000 cycles at a current density of 0.5 A g−1, and the zinc hybrid capacitors for more than 18, 000 cycles at 1 A g−1. And an ionic skin (i-skin) based on acrylamide and 1-(3-Sulfopropyl)-2-Vinylpyridinium betaine of polymer hydrogel electrolyte is assembled and it can stably detect physiological signals. A zwitterionic hydrogel electrolyte is constructed based on polyacrylamide/poly(1-(3-sulfopropyl)-2-vinylpyridinium betaine, excellent mechanical strength and high ion conductivity is advocated for zinc metal batteries. The sulfonate anionic groups of the polyacrylamide/poly(1-(3-sulfopropyl)-2-vinylpyridinium betaine side chain with negatively charged can absorb onto Zn anodes to refine Zn-electrolyte interface affinity and prevent the H 2 O molecules in the Zn2+ solvation structure from contacting with Zn anodes. In addition, the sulfonate anionic groups can also guide the Zn2+ migration, and decrease the desolvation energy for fast Zn/Zn2+ reversibility. Moreover, the mechanical property of the hydrogel is enhanced by the Hofmeister effect between –SO 4 2- and polyacrylamide/poly(1-(3-sulfopropyl)-2-vinylpyridinium betaine, to accommodate the deformation of the electrodes. [Display omitted] • The zwitterion hydrogel with high interfacial affinity is fabricated. • The zwitterion hydrogel improves the stability of Zn anodes. • The Zn mental battery/capacitor exhibits outstanding cycle stability and life. • The ionic skin demonstrates stable signal monitoring for various body parts. [ABSTRACT FROM AUTHOR]

Vanadium nitride is a negative material with extensive application prospects in energy storage fields; however, its stability under long cycles and high current density is still an urgent problem to be solved. The preparation of nanoscale vanadium nitride structures with carbon protection has become mainstream to solve these problems. Thus, designing and constructing a more optimized vanadium nitride and carbon composite structure is the key to improving the performance of electrodes. Herein, the carbon sheet mosaiced with the vanadium nitride quantum dots is fabricated by self-assembly of V3+ and the deprotonated poly (paraphenylene terephthalamide) chains. As supercapacitors negative materials, the vanadium nitride quantum dots@carbon exhibits high specific capacitance reaching 532 F g−1 at the current density of 0.5 A g−1 and capacity retentions of 67% after 5, 000 cycles. The good electrochemical performance is attributed to the continuous fast electron transmission path and amounts of the electrochemical reaction site of the mosaic structure. This study offers a facile and novel method for vanadium nitride-based electrode challenges. [Display omitted] • Vanadium nitride quantum dots@carbon with mosaic nanostructure is fabricated by self-assembly strategy. • Mosaic structures provide continuous electron transport pathways and more reaction sites. • The prepared vanadium nitride quantum dots@carbon anode materials exhibit a high capacity of 532 F g−1. [ABSTRACT FROM AUTHOR]