Regulating the local glass networks to enhance the optical performance of CsPbX3 (X = Cl, Br, I) quantum dots embedded in zinc borosilicate glasses via GeO2

Abstract

All inorganic CsPbX₃ (X = Cl, Br, I) perovskite quantum dots (QDs) have excellent optical properties, and show great potential in optoelectronic devices, information storage, wide color gamut backlight display and other fields. In previous work, embedding CsPbBr₃ QDs into glass matrix through in-situ crystallization has become an important strategy to improve the stability of quantum dots. However, few reports have been made on the synthesis of high-quality whole family CsPbX₃ QDs glass by melt-quenching method. Herein, CsPbX₃ QDs glasses with full visible spectrum were synthesized by a closed melt-quenching technique. And the precise content of GeO₂ was used to regulate the size of glass network gaps to accommodate different sizes of CsPbX₃ QDs. The deconvoluted infrared spectra confirmed that the introduction of GeO₂ was beneficial to the increase of non-bridging oxygen in the rigid structure, the number and percentage of [BO₃] triangular units increased correspondingly, and the glass network changed in a three-dimensional and looser benign way, which was beneficial to the growth of large-size QDs. Finally, the luminescent properties of CsPbCl₂Br, CsPbBr₃ and CsPbBrI₂ QDs glasses were improved respectively. The optimized CsPbX₃ QDs glasses have tunable luminescence in the full visible spectrum (414–692 nm), improved photoluminescence quantum yield (PLQY, ∼53.06 %) and longer decay lifetime, and excellent stability. Finally, the construction of a white light-emitting diode (WLED) device shows that CsPbX₃ QDs glass has potential applications in solid-state lighting.