Advances and prospects of g-C₃N₄ in lithium-sulfur batteries

Lithium-sulfur (Li-S) batteries are regarded as one of the most promising candidates for next-generation high-energy-density storage systems due to their superior energy density, cost-effectiveness, and environmental friendliness. However, several critical challenges impede their practical application, including the shuttle effect, low conductivity, and volume expansion. Graphitic carbon nitride (g-C₃N₄), with its unique structure and properties, offers potential advantages in catalysis, polarization inhibition, electron conductivity, and sulfurization resistance, which may address these issues. This review concentrates on applying g-C₃N₄ material to enhance Li-S battery performance. The research progress on g-C₃N₄ in this context is explored from two primary perspectives: the modification of g-C₃N₄ itself and its compounding with other materials. Regarding the modification of g-C₃N₄, the focus is on defect engineering and the nanocrystallization of its structure. In terms of composites, the review examines the use of g-C₃N₄ doped with metals, non-metals, graphene, porous carbon, and heterojunctions in electrodes and electrolytes. Ultimately, this review proposes strategies for the rational design of g-C₃N₄ materials to optimize their application in Li-S batteries. Reviewing the current research progress and trends aims to provide new insights and directions for future research in the field.