• • The ZnO@ZnMgO core-shell ETL increases the average electron population (<N_e>) in the QD emissive layer from 0.33 (ZnMgO-only) to 0.61 at 4 V, nearly doubling the pre-charged QD fraction and directly enhancing radiative recombination efficiency.
• • Green QLEDs fabricated with the ZnO@ZnMgO ETL achieve a peak external quantum efficiency (EQE) of 30.66%, a maximum luminance of 1,615,039.85 cd/m2, and a low turn-on voltage of approximately 2 V, setting new benchmarks for solution-processed QLEDs.
• • The T95 operational lifetime exceeds 29,000 hours at an initial luminance of 1,000 cd/m2, representing a significant improvement in stability, which is critical for commercial display applications requiring long-term reliability.
• • The core-shell design synergistically combines the high electron conductivity of the ZnO core with the low defect density of the ZnMgO shell, mitigating interfacial quenching and charge trapping, thereby addressing the long-standing bottleneck of insufficient electron injection and interface-induced efficiency loss in QLEDs.