Engineering Interfacial Synergy and Cationic Modulation in V-Doped Ni3S2/MnS Nanoflower Heterostructures for High-Performance Hybrid Supercapacitor

This work reports a synergistic dual‑engineering strategy that integrates heterointerface construction with cationic modulation for developing high‑performance supercapacitor electrodes. Three‑dimensional V‑doped Ni 3 S 2 /MnS nanoflower heterostructures are successfully synthesized via a facile hydrothermal‑sulfidation method. The in situ‑formed heterojunctions create built‑in electric fields that accelerate charge transfer, while V 3+ doping optimizes the electronic structure and provides additional redox‑active sites. Benefiting from this rational design, the V‑Ni 3 S 2 /MnS electrode delivers a high specific capacity of 2725  F g −1 at 1  A  g −1 , retains 1700  F  g −1 (62.4% retention) at 10  A g −1 , and maintains 92.4% capacity retention after 5000 cycles. Theoretical calculations confirm the enhanced charge‑transfer kinetics in the heterostructure. When assembled into an asymmetric supercapacitor with activated carbon, the full cell achieves an energy density of 66.3  Wh  kg −1 at 1500  W  kg −1 . This study provides new insights into the design of heterostructured electrode materials for advanced energy storage applications. Graphical This study achieved an innovative design of high-performance hybrid supercapacitor electrode materials by constructing a V-doped Ni 3 S 2 /MnS nanoflower heterostructure. This material employed a synergistic strategy of interface engineering and cation regulation, achieving a high specific capacity of 2725 F g − 1 at a current density of 1 A g − 1 , maintaining 1700 F g − 1 even at a large current of 10 A g − 1 , and demonstrating excellent cycle stability of 92.4%. Theoretical calculations indicated that the built-in electric field at the heterointerface significantly enhanced the charge transfer kinetics. The assembled asymmetric supercapacitor device achieved an energy density of 66.3 Wh kg − 1 at a power density of 1500 W kg − 1 . This research provides a new idea for designing high-performance energy storage materials through multi-scale structure regulation.