Photoluminescence Enhancement Mechanism of Red-Emitting Y₂O₃-Modified CsPbBrI₂ Perovskite Quantum Dots Glasses

Perovskite quantum dots (PQDs) have shown great potential in lighting and display fields due to their excellent optical properties. However, their low red emission efficiency and poor environmental stability severely limit their practical applications. In this study, red-emitting Y2O3-modified CsPbBrI2 PQD glass was prepared by high-temperature melt quenching and heat treatment methods with high luminescence and stability. The incorporation of Y3+ ions leads to a partial replacement of Pb2+ ions, resulting in a contraction of the crystal lattice. Y3+ ions will interact with the surface defects and halogen vacancies of PQDs to passivate these defect sites, thereby reducing the nonradiative recombination rate. The photoluminescent quantum yield increased from 5.6% to 56.4%, which is increased to ten times the original. The prepared CsPbBrI2 PQD glass samples exhibited good thermal stability and water stability. Furthermore, red-emitting LED and WLED devices based on CsPbBrI2 PQD glass achieved high color rendering index and good luminescent performance and stability. This paper presents Y2O3-modified CsPbBrI2 PQD glass with efficient red-emitting emission and demonstrates its application potential in solid-state lighting and display technologies.