Improved blue quantum dot light-emitting diodes via chlorine passivated ZnO nanoparticle layer*

In blue quantum dot light emitting diodes (QLEDs), electron injection is insufficient, which would degrade device efficiency and stability. Herein, we employ chlorine passivated ZnO nanoparticles as electron transport layer to facilitate electron injection into QDs effectively. Moreover, it suppresses exciton quenching at the QD/ZnO interface by blocking charge transfer channel. As a result, the maximum external quantum efficiency of blue QLED was increased from 2.55% to 4.60%, and the operation lifetime of blue QLED was nearly 4 times longer than that of the control device. Our work indicates that election injection plays an important role in blue QLED efficiency and stability.

Automated summary

Insufficient electron injection in blue QLEDs can degrade device efficiency and stability. By using chlorine passivated ZnO nanoparticles as electron transport layer, electron injection into QDs is facilitated and exciton quenching is suppressed, leading to improved efficiency and stability of blue QLEDs.