Advancing aqueous zinc-ion batteries with carbon dots: A comprehensive review

Recent years have witnessed a surge in research on aqueous zinc-ion batteries (AZIBs) due to their low cost, stability, and exceptional electrochemical performance, among other advantages. However, practical manufacturing and deployment of AZIBs have been hindered by challenges such as low energy density, significant precipitation-related side reactions, slow ion migration, and dendritic growth. Addressing these issues and enhancing the practical application of AZIBs necessitates the development of novel materials. Carbon dots (CDs), with their distinctive structure and superior electrochemical properties, represent an innovative class of carbon-based materials with broad potential applications for optimizing AZIBs' performance. This study offers a comprehensive review of how CDs can address the aforementioned challenges of AZIBs. It begins with an overview of AZIBs composition and mechanism before delving into the classification, preparation techniques, and functionalization strategies of CDs. The review also thoroughly summarizes the sophisticated roles of CDs as modifiers in electrolytes and electrodes, both positive and negative, and briefly discusses their potential application in membranes. Additionally, it provides a summary of current issues and difficulties encountered in utilizing CDs in AZIBs. This review aims to provide insights and guidance for designing and manufacturing the next generation of high-performance AZIBs.