Insights into dynamic structural evolution and its sodium storage mechanisms of P2/P3 composite cathode materials for sodium-ion batteries.

Cobalt substitution for manganese sites in Na 0.44 MnO 2 initiates a dynamic structural evolution process, yielding a composite cathode material comprising intergrown P2 and P3 phases. The novel P2/P3 composite cathode exhibits a reversible phase transition process during Na + extraction/insertion, showcasing its attractive battery performance in sodium-ion batteries.