Titanium Carbide (MXene) as a Current Collector for Lithium-Ion Batteries

MXenes are a class of two-dimensional (2D) transition-metal carbides and nitrides that are currently at the forefront of 2D materials research. In this study, we demonstrate the use of metallically conductive free-standing films of 2D titanium carbide (MXene) as current-collecting layers (conductivity of ∼8000 S/cm, sheet resistance of 0.5 Ω/sq) for battery electrode materials. Multilayer Ti₃C₂T <i>_x</i> (T <i>_x</i> : surface functional groups -O, -OH, and -F) is used as an anode material and LiFePO₄ as a cathode material on 5 μm MXene films. Our results show that the capacities and rate performances of electrode materials using Ti₃C₂T <i>_x</i> MXene current collectors match those of conventional Cu and Al current collectors, but at significantly reduced device weight and thickness. This study opens new avenues for developing MXene-based current collectors for improving volumetric and gravimetric performances of energy-storage devices.