In-Situ Monitoring of Charge Storage Mechanism from Ti3C2Tx MXene Nanostructures via Ionic Liquid Etching and Intercalation

MXenes are promising materials for energy storage due to their high electrical conductivity and unique layered structure. This study demonstrates the dual role of 1-Butyl-3-methylimidazolium tetrafluoroborate (BMImBF4) as both an etching agent and an intercalation medium for synthesizing Ti3C2Tx MXene with enhanced electrochemical performance. In-situ Raman and XRD analyses show that BMIm+ ions intercalate between MXene layers, stabilizing the nanoscale (002) interlayer spacing, preventing restacking and improving ion transport. When tested in the H2SO4–BMImBF4 hybrid electrolyte, the Ti3C2Tx MXene delivers a capacitance of 228.7 F g–1 at a scan rate of 1 mV s–1, compared to 179.9 F g–1 in pure H2SO4, measured on the same batch of materials. This demonstrates that incorporating BMImBF4 into H2SO4 significantly enhances the charge storage capability of Ti3C2Tx MXene. These findings highlight the effectiveness of BMImBF4 in optimizing charge storage and reinforce the potential of ionic liquids for advanced MXene-based energy storage systems.