A reliable power supply system is the core support for the stable operation of biomedical devices, and energy storage devices with integrated safety, flexibility, and biocompatibility represent a critical bottleneck in the development of next-generation wearable/implantable medical devices. Flexible zinc-ion batteries (FZIBs), leveraging their inherent safety features, excellent biocompatibility, and cost-effectiveness advantages, have emerged as highly promising power solutions in this field. However, they are still limited by issues, such as cathode structural instability, zinc anode dendrite growth, and insufficient ionic conductivity and mechanical properties of electrolytes/separators. MXene, as an emerging two-dimensional material with unique physicochemical properties, is an ideal modification candidate for FZIBs performance breakthroughs. This review systematically summarizes the preparation strategies of MXene-based flexible electrodes, the working mechanisms of FZIBs, and the existing challenges of their core components. It focuses on discussing the application progress of MXene in the cathodes, anodes, electrolytes, and separators of FZIBs, and deeply analyzes the mechanism by which structural regulation enhances battery flexibility and optimizes electrochemical performance. On this basis, focusing on wearable/implantable devices’ practical application needs, their biomedical application potential is demonstrated. Finally, future development directions are prospected from three dimensions: material design, device integration, and clinical translation, aiming to provide theoretical and technical guidance for the construction of high-performance MXene-based FZIBs, accelerate their industrial application in the field of precision medicine, and promote the in-depth integration of flexible energy storage technology and biomedical engineering.

The importance of the oxygen reduction reaction (ORR) in fuel cells and zinc-air batteries is self-evident, and effective catalysts could significantly improve the catalytic efficiency of ORR. Single-atom catalysts are gaining increasing interest due to their high atom efficiency and effective catalytic performance compared to other catalyst types. While the optimal loading of catalytic sites in single-atom catalysts significantly influences their catalytic efficiency. However, creating stable single-atom catalysts with high-loading remains a difficult task. Therefore, we showcase and describe the latest developments in techniques for producing single-atom catalysts with high-loadings. In addition, the performance of noble metal, non-precious metal, and diatomic catalysts in ORR processes is summarized. What’s more, the key difficulties and opportunities in the sector are demonstrated by examining the synthesis techniques and evaluating the performance and structure. This review will help researchers to advance the research process of high-loading single-atom catalysts and accelerate their practical application in the field of ORR research.