The influence of H2O and O2 on the optoelectronic properties of inverted quantum-dot light-emitting diodes


The influence of H2O and O2 on the performances of Mg-doped zinc oxide (ZnMgO) and ZnMgO-based inverted quantum-dot light-emitting diodes (QLEDs) are studied. With the involvement of H2O from ambience, ZnMgO exhibits a high conductivity, whereas the resultant QLEDs show a low efficiency. The efficiency of QLEDs can be enhanced by annealing ZnMgO in H2O-free glovebox; however, the uniformity and the current of the devices are degraded due to the presence of O2, which adsorbs on the surface of ZnMgO and captures the free electrons of ZnMgO. By exposing the devices with ultraviolet (UV) irradiation, the adsorbed O2 can be released, consequently leading to the increase of driving current. Our work discloses the influence of the annealing ambience on the conductivity of ZnMgO, and reveals the interaction of H2O/O2 and UV with the ZnMgO and its effect on the performance of the resultant inverted QLEDs, which could help the community to better understand the mechanisms of ZnMgO-based QLEDs.

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This work was supported by the National Natural Science Foundation of China (No. 61775090) and the Guangdong Natural Science Funds for Distinguished Young Scholars (No. 2016A030306017).

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Correspondence to Shuming Chen.

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Chen, Z., Qin, Z., Su, S. et al. The influence of H2O and O2 on the optoelectronic properties of inverted quantum-dot light-emitting diodes. Nano Res. (2021).

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  • quantum-dot
  • light-emitting diodes
  • ZnMgO
  • oxygen
  • water