Prussian blue and its analogues as cathode materials for Na-, K-, Mg-, Ca-, Zn- and Al-ion batteries

Prussian blue and its analogs (PB/PBAs) are competitive candidates for cathode materials of rechargeable metalion batteries (monovalent metal such as Na and K and multivalent metal, e.g. Mg, Ca, Zn, and Al) due to their stable frame structures, tunable redox sites, and facile synthesis methods. This paper comprehensively reviews the research progress of PB/PBAs-based cathode materials of metal-ion batteries in terms of their synthesis, structural/composition characteristics, electrochemical performance, functional mechanisms, applications and recycling in electrical energy storage. For facilitating the research and development, some technical challenges are analyzed and future research directions are also proposed for overcoming the challenges toward their practical applications.