Synergistic Integration of SrFeO3 Nanoparticles With Exfoliated MXene (Ti3C2Tx/V2CTx) Nanosheets for High Performance Supercapacitors.

The performance of supercapacitors is often limited by conventional electrode materials, which typically necessitate a compromise between energy density, power density, and cycling stability. While two-dimensional MXenes offer high conductivity and surface area, their practical application is hindered by restacking and oxidative degradation. This study introduces a novel heterostructured composite designed to overcome these limitations. For the first time, we fabricate a porous, exfoliated network by integrating zero-dimensional SrFeO3 nanoparticles with Ti3C2Tx and V2CTx MXenes via a straightforward mechanical mixing process. In this architecture, the SrFeO3 nanoparticles fulfill a dual role: they inhibit MXene restacking and contribute significant pseudocapacitance via Faradaic reactions. The synergistic coupling between the conductive MXene scaffolds and the redox-active nanoparticles yields exceptional electrochemical performance. The optimized Ti3C2Tx@SrFeO3 and V2C@SrFeO3 electrodes achieve specific capacitances of 752 and 972 F g- 1, respectively, at 1 A g- 1, alongside excellent rate capability. Asymmetric supercapacitor devices assembled with these composites deliver high energy densities of up to 52.91 Wh kg- 1 and exhibit outstanding long-term stability, retaining over 93.9% of their initial capacitance after 5000 cycles. This work establishes the MXene/SrFeO3 heterostructure as a promising platform for high performance energy storage.