Achieving Fast and Stable Sodium Storage in Na 4 Fe 3 (PO 4 ) 2 (P 2 O 7 ) via Entropy Engineering

. When paired with a hard carbon (HC) anode, HE-NFPP//HC full cell exhibits a favorable cycling durability of 1000 cycles. This high-entropy engineering offers a feasible route to improve the electrochemical performance of NFPP and provides a blueprint for exploring high-performance SIBs.