Fabrication of ZnO dual electron transport layer via atomic layer deposition for highly stable and efficient CsPbBr3 perovskite nanocrystals light-emitting diodes

Electron transport layers (ETLs) are important components of high-performance all-inorganic perovskite nanocrystals light-emitting diodes (PNCs-LED). Herein, atomic layer deposition (ALD) of inorganic ZnO layer is combined to the organic 1,3,5-Tris(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi) to form dual ETLs to enhance both the efficiency and stability of PNCs-LED simultaneously. Optimization of ZnO thickness suggested that 10 cycles ALD yields the best performance of the devices. The external quantum efficiency of the device reaches to 7.21% with a low turn-on voltage (2.4 V). Impressively, the dual ETL PNCs-LED realizes maximum T (50) lifetime of 761 h at the initial luminance of 100 nit, which is one of the top lifetimes among PNCs-LEDs up to now. The improved performance of dual ETL PNCs-LED is mainly due to the improved charge transport balance with favorable energy level matching. These findings present a promising strategy to modify the function layer via ALD to achieve both highly efficient and stable PNCs-LED.

Automated summary

In this study, atomic layer deposition (ALD) is combined with organic materials to form dual electron transport layers (ETLs) to improve the efficiency and stability of perovskite nanocrystals light-emitting diodes (PNCs-LEDs). By optimizing the thickness of the inorganic ZnO layer, the device achieves a high external quantum efficiency of 7.21% and a low turn-on voltage of 2.4V. Moreover, the dual ETL PNCs-LED exhibits a long lifetime of 761 hours.