Engineering Interfacial Synergy and Cationic Modulation in V‐Doped Ni 3 S 2 /MnS Nanoflower Heterostructures for High‐Performance Hybrid Supercapacitor

Abstract

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.