A review on electrochemical performance of Mxene/carbon-based materials for aqueous zinc-ion batteries

Owing to their high conductivity, hydrophilicity, and layered structures, MXenes have recently emerged as promising electrode materials for aqueous zinc-ion batteries (ZIBs). However, issues such as restacking, surface oxidation, and limited long-term stability restrict their practical performance. Carbon materials, including graphene, carbon nanotubes, carbon nanofibers, activated carbon, and porous carbons, provide ideal counterparts for MXenes due to their excellent conductivity, structural tunability, and mechanical robustness. The integration of MXenes with carbon not only prevents sheet restacking and enhances ion/electron transport but also improves electrode stability and cycling reversibility. In this review, recent progress in MXene/carbon composites for ZIBs is summarized, focusing on their synthesis strategies, structural engineering, and electrochemical behavior. Particular attention is given to the synergistic storage mechanisms, dimensional matching, and the influence of heteroatom doping or porous architectures on charge storage kinetics. Beyond laboratory-scale studies, the scalability of composite fabrication, electrolyte optimization, and full-cell demonstrations are highlighted as crucial steps toward practical implementation. Finally, existing challenges such as green synthesis routes, interfacial regulation, and long-term cycling stability are discussed, and future perspectives are proposed to guide the rational design of MXene/carbon hybrids as next-generation high-performance ZIB electrodes. • Although aqueous rechargeable mildly acidic Zn-MnO2 batteries are known for being non-toxic, inexpensive, and safe, they continue to face a significant challenge: their inadequate energy density resulting from a variety of electrochemical reaction mechanisms. • We evaluate the compromises among Zn2+ intercalation, H+ conversion, and Mn2+ stripping plating reactions within the identical MnO2 polymorph. Additionally, we investigate the relationship between the structure and properties of manganese dioxide in conjunction with metal-organic frameworks, MXenes, and biochar. • The investigation delves into the possibility of doping MnO2 chemistries and utilizing nanocomposites to enhance energy storage capabilities.