Aqueous potassium ion batteries (APIBs) have emerged as a promising candidate for next-generation energy storage systems due to their inherent safety, cost-effectiveness, and environmental sustainability. APIBs utilize water-based electrolytes, which significantly reduce the risk of flammability associated with organic solvent-based electrolytes. Considering the potential applications of APIBs in grid-scale energy storage and portable electronics, it is of great significance for the study of APIBs. Among the components of APIBs, the cathode materials play a critical role and are the primary factors determining the energy density and power density of aqueous batteries. Therefore, to advance cathode materials, it is essential to summarize recent research progress. The review introduces various types of cathode materials, including Prussian blue and its analogs, metal oxides, MXenes, and polyanion-type compounds. It summarizes recent advances in cathode materials for APIBs, focusing on the advantages of these materials as well as the challenges they face and strategies for optimization. Finally, the review provides a summary and outlook on how to enhance the performance of cathode materials in APIBs. The purpose of this review is to provide some ideas for the development of new and efficient APIBs cathode.

中文翻译：

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水系钾离子电池正极材料的进展


水系钾离子电池 （APIB） 因其固有的安全性、成本效益和环境可持续性而成为下一代储能系统的有前途的候选者。APIB 使用水基电解质，可显著降低与有机溶剂基电解质相关的易燃风险。考虑到 APIBs 在电网规模储能和便携式电子领域的潜在应用，对 APIB 的研究具有重要意义。在 APIB 的组成部分中，正极材料起着至关重要的作用，是决定水系电池能量密度和功率密度的主要因素。因此，要推进正极材料的发展，必须总结最近的研究进展。综述介绍了各种类型的正极材料，包括普鲁士蓝及其类似物、金属氧化物、MXenes 和聚阴离子型化合物。它总结了 APIB 正极材料的最新进展，重点介绍了这些材料的优势以及它们面临的挑战和优化策略。最后，该综述对如何提高 APIB 中正极材料的性能进行了总结和展望。本文旨在为开发新型高效的 APIB 阴极提供一些思路。