In-Situ Monitoring of Charge Storage Mechanism from Ti ₃ C ₂ T _x MXene Nanostructures via Ionic Liquid Etching and Intercalation

High Resolution Image Download MS PowerPoint Slide 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 (BMImBF 4 ) as both an etching agent and an intercalation medium for synthesizing Ti 3 C 2 T x 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 H 2 SO 4 –BMImBF 4 hybrid electrolyte, the Ti 3 C 2 T x 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 H 2 SO 4, measured on the same batch of materials. This demonstrates that incorporating BMImBF 4 into H 2 SO 4 significantly enhances the charge storage capability of Ti 3 C 2 T x MXene. These findings highlight the effectiveness of BMImBF 4 in optimizing charge storage and reinforce the potential of ionic liquids for advanced MXene-based energy storage systems.