A superior sodium-ion battery based on tubular Prussian blue cathode and its derived phosphide anode

Sodium-ion batteries are receiving incremental attention as a promising alternative of the commercial lithium-ion batteries. However, it remains a challenging task to fully explore suitable cathode and anode materials for assembling a full cell with attractive Na-ion storage properties. Herein, we demonstrate a superior sodium-ion battery by pairing a tubular Prussian blue (PB) cathode and its derived phosphide anode. The tubular configuration endows the PB with fast reaction kinetics and thus delivers a large specific capacity of 94.4 mAh g⁻¹ even at a high rate of 5.0 A g⁻¹. The PB-derived phosphide is featured by encapsulation of FeP nanoparticles into a conductive carbon matrix, which enables remarkable sodium energy storage likewise. Impressively, the as-assembled sodium-ion full cell exhibits an unprecedented capacity of 105.3 mAh g⁻¹ at 2.0 A g⁻¹ and good cycling lifespan. The present study offers a homologous design strategy based on PB and its derivatives for constructing outstanding sodium-ion full cells.