A synergistic approach combining Cu doping and a CuO/C intertwined network for the Na 4 Fe 3 (PO 4 ) 2 P 2 O 7 cathode: enhancing high-rate performance and structural robustness

A valence-controlled synergistic dual-modification integrates Cu doping and CuO/C coating into a lychee-like NFPP. This strategy suppresses inactive impurities, enabling exceptional high-rate capability and long cycling stability.