2D/2D Borophene/Ti2NbC2Tx MXene hybrids as advanced electrodes for supercapacitors

Two-dimensional (2D) hybrid electrodes combining complementary charge-storage mechanisms represent a promising approach for advanced supercapacitors. In this work, few-layer β-borophene nanosheets were synthesised via a modified Hummers' method and integrated with Ti2NbC2Tx MXene to form 2D/2D hybrid electrodes. Structural characterization confirmed successful borophene exfoliation, MXene–borophene heterostructure formation with locally ordered domains and enhanced ion accessibility. Electrochemical measurements demonstrated that hybrid electrodes significantly outperformed pristine MXene and borophene. The MX-B10 composition exhibited the highest specific capacitance, superior rate capability, and optimal charge-transfer kinetics attributed to synergistic surface-controlled capacitance from borophene and diffusion-assisted ion transport in MXene. A symmetric solid-state supercapacitor (SSSC) assembled with MX-B10 electrodes achieved 54 Wh kg−1 at ~300 W kg−1, retaining 23.2 Wh kg−1 at ~7.6 kW kg−1 with ~97% capacitance retention after extended cycling, These results highlight the potential of borophene–MXene heterostructures for high-performance energy storage applications. © 2026 Elsevier B.V.