Na4MnV(PO4)3, characterized by cost-effectiveness, high voltage, and tunable chemical structure, has drawn considerable attention. However, the practical deployment is hindered by drastic local structural distortions induced by over two electron transfers, coupled with intrinsically low electronic conductivity. Herein, a Schottky and 3d-orbital coupling design paradigm is performed to synergistically tailor the TM-O coordination environment and interfacial structures, thus breaking the dual bottlenecks of poor electrode kinetics and structural fragility. Therefore, the prepared Schottky-orbital coupling mediated Na4MnV(PO4)3 (SOMV) cathode exhibits continuous multistep redox with a reversible discharge capacity of 143.9 mAh g-1 at 0.1 C. Theoretical calculations and experiment demonstrate that the in-situ generated metallic Ni2P particles establish intimate contact with semiconducting phosphate particles, inducing the built-in electric field and thus facilitating the coupled ion-electron transfer and elevating the reaction-limited current. Eventually, the SOMV cathode achieves a remarkable rate (82.5 mAh g-1 at 30 C) and fast-charging performance (26 s to reach 88.5 mAh g-1). Moreover, the multiple TM 3d-orbital coupling and reinforced TM─O bonds of SOMV grant the excellent long-term cycling stability (75.0% capacity retention after 10 000 cycles at 30 C). A universal paradigm for boosting the coupled ion-electron transfer is established via synergistic engineering of electronic and structural properties.
Du et al. (Mon,) studied this question.