Dual-Facets Emissive Quantum-Dot Light-Emitting Diode Based on AZO Electrode

We report on a green, dual emissive quantum-dot light-emitting diode (QLED) using alumina (Al)-doped ZnO (AZO) to adjust the band offset between the cathode and QD-emitting layers. The dual emissive QLED structure was designed by enhancing the efficient hole injection/transfer and slowing down the electron injection/transfer from AZO to the QD. The QLEDs presented a maximum luminance of 9450 cd/m(2), corresponding to a power efficiency of 15.7 lm/W, a current efficiency of 25.5 cd/A, as well as a turn-on voltage of 2.3 V. It is worth noting that the performance of the dual emissive QLED is comparable to that of a single emissive QLED. Therefore, there is a 1.3-fold enhancement in the performance of the QLED based on the AZO cathode due to the balanced charge injection/transfer.