Near-Unity Quantum Yield and Superior Stable Indium-Doped CsPbBrxI3-x Perovskite Quantum Dots for Pure Red Light-Emitting Diodes

Although all-inorganic CsPbBrxI3-x perovskite quantum dots (PeQDs) are increasingly being used as a competitive material for pure red perovskite light-emitting diodes (PeLEDs), they suffer from low luminescent ability and poor stability. In this study, an In3+-doped CsPbBrxI3-x PeQD solution exhibits a near-unity photoluminescence quantum yield (PLQY) of approximate to 99.8% and superior stability for more than half a year in atmosphere. As far as known, this is the highest PLQY and stability achieved for mixed halide PeQDs. In3+ ion doping not only reduces the surface vacancy defects because of the partial substitution of Pb2+ by the smaller radii of In3+ ions, but also enhances the formation energy of CsPbBrxI3-x PeQDs based on first-principles calculations. Compared with pristine LEDs based on CsPbBrxI3-x, the pure red PeLEDs based on In3+-doped CsPbBrxI3-x display a higher luminance of 423 cd m(-2), fivefold external quantum efficiency improvement up to 11.2%, and increased stability, providing a feasible and promising perspective for developing In3+-doped CsPbBrxI3-x PeQDs applied efficiently in advanced light emitters for solid-state lighting and displays.

Automated summary

The study introduces In3+ ion doping in CsPbBrxI3-x perovskite quantum dots, achieving a near-unity photoluminescence quantum yield and superior stability. The doped PeQDs exhibit higher luminance, fivefold external quantum efficiency improvement, and increased stability compared to pristine LEDs, suggesting promising applications in advanced light emitters for solid-state lighting and displays.