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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]

Nanomaterials are widely used in many fields for their unique physical and chemical properties and especially demonstrate irreplaceability in energy storage systems. In this paper, a novel composite of copper sulfide with hypha-like core-shell nano-structure is synthesized by in situ phase inversion method, which serves as high stability negative electrode materials of zinc-ion batteries (ZIBs). The unique structure facilitates efficient electron and ion transport, enhances the kinetics of electrochemical reactions, and effectively suppresses the undesired expansion and decomposition of transition metal compounds. As a result, the half battery exhibits high specific capacity (250.2 mAh g -1 at 0.1 A g -1 ), reliable rate performance, and cycle stability (98.3 mAh g -1 at 1 A g -1 after 500 cycles). Additionally, when assembled with Zn x MnO 2 positive to form a full battery, it demonstrates good cycling capacity at an intermediate current density of 2 A g -1 , while maintaining excellent structural stability over 5,000 cycles (61% retention)., (© 2024 Wiley‐VCH GmbH.)