Solution-Processed 2D Titanium Carbide MXene Electrodes for Efficient Quantum Dot Light-Emitting Diodes

Indium tin oxide (ITO) is commonly used as the bottom electrode of QLEDs, which limits the application of QLEDs in low-cost flexible displays. Here, we demonstrate a high-performance QLED with solution-processed 2D Ti3C2Tx MXene bottom electrodes. The MXene is obtained by etching aluminum (Al) from titanium aluminum carbide (Ti3AlC2) through a simple wet chemical synthesis procedure. By improving the morphology of the MXene electrode through a heat-press process during the film formation process, QLEDs with the MXene electrodes can be successfully fabricated. Due to the reduced hole injection barrier between MXene and HIL, the resulting MXene-based QLEDs can exhibit an excellent external quantum efficiency (EQE) of 27.50% and a high current efficiency of 29.05 cd/A, which are ∼1.3- and ∼1.2-fold higher than those of conventional QLEDs, respectively. We believe that the developed high-efficiency QLEDs with solution-processed MXene electrodes will promote the practical application of QLEDs in low-cost, flexible, and transparent displays.