Trace Cu Doping Enabled High Rate and Long Cycle Life Sodium Iron Phosphate Cathode for Sodium-Ion Batteries.

NaFe(PO)(PO) (NFPP) is currently receiving a lot of attention, as it combines the advantages of NaFePO and NaFePO in terms of cost, energy density, and cycle stability. However, the issues of intrinsic poor electronic conductivity and difficult high-purity preparation may impede its practical application. Herein, the pivotal role of Cu doping in strengthening the polyanion structure and improving its electrochemical properties is comprehensively investigated.

Rational design of hierarchical FeSe encapsulated with bifunctional carbon cuboids as an advanced anode for sodium-ion batteries.

Earth-abundant transition-metal selenides (TMSs) have aroused great interest towards their application in sodium-ion batteries (SIBs). Herein, we present Fe-based Prussian blue analogs (PBA) modified by graphene oxide as precursors to synthesize FeSe2 nanoparticles within a nitrogen-doped carbon (NC) matrix and graphene layer (FeSe2/NC@G). The bifunctional carbon wrapped FeSe2/NC@G shows excellent sodium-storage performance with a large reversible capacity of 331 mA h g-1 at 5.