CaO modulated dual-phase CsPb2Br5/CsPbBr3 perovskite nanocrystal glasses with enhanced stability for backlit display.

All-inorganic perovskite nanocrystals (PNCs) hold tremendous prospect in optoelectronics, while the instability has always troubled us to the wide application of perovskite materials. Here, the dual-phase CsPb 2 Br 5 /CsPbBr 3 PNCs were precipitated in the phosphosilicate glass matrix by a melt-quenching method for the first time. Impressively, the introduction of alkaline earth metal oxide CaO was utilized to adjust glass structure, and successfully realizing the conversion between the two phases. To our surprise, the CsPb 2 Br 5 /CsPbBr 3 @glass (PNG) owned the optical characteristics such as narrowband emission, high photoluminescence quantum yield (PLQY ∼ 52%) and tunable PL emission (505–526 nm). In addition, the obtained CsPb 2 Br 5 /CsPbBr 3 @glass exhibited excellent thermal, water and light stabilities. More excitingly, a conceptual experiment was carried out through commercial TFT-LCD devices, and the color gamut of the prepared PNG@PET yellow-emitting composite film covered 130% of National Television System Committee (NTSC) and 97% of Rec.2020, and maintained excellent display performance even after 72 h of continuous operation. This work undoubtedly not only provided a new avenue to control the precipitate composite perovskites in glass, but also demonstrated composite perovskites materials have great potentials for future practical backlit display applications. • Two-phase perovskite CsPbBr 3 /CsPb 2 Br 5 @glass was precipitated in glass matrix for the first time. • Introduction of alkaline earth metal oxide CaO successfully realized the conversion between the two phases. • The obtained CsPb 2 Br 5 /CsPbBr 3 @glass exhibited excellent thermal, water and light stabilities. • The obtained wide color gamut reached 130% of the NTSC standard color gamut, covered 97% of the Rec.2020 color gamut. • After 72 h of continuous operation, the display performance was almost unchanged. [ABSTRACT FROM AUTHOR]