TiO2 doping promoted nucleation of CsPbX3 (X = Cl, Br, I) quantum dots in glass with improved luminescent performance and stability

Abstract

Stability hinders further development of all-inorganic CsPbX3 (X = Cl, Br, I) quantum dots (QDs) although they exhibit promising prospects in optoelectronic applications. Coating perovskite quantum dots (PQDs) with a glass network to form QD glass can significantly improve their stability. However, the dense glass network degrades their luminescent performance. In this work, the crystallization behavior of PQDs in glass and better luminescence properties are prompted by introducing titanium dioxide into borosilicate glass. The luminescence intensity of TiO2-doped CsPbBr3 QD glass is increased by 1.6 times and the PLQY is increased from 49.8 % to 79 % compared to the undoped glass. Evidence proves that the improved properties are attributed to the enhanced nucleation effect of titanium dioxide during the annealing process. Benefiting from the densification of the glass network caused by titanium dioxide doping, the stability of the PQD glass is further improved. LED devices with an ultra-wide color gamut that fully covers the NTSC1953 standard and achieves 128.6 % of the NTSC1953 standard as well as 91.1 % of the Rec.2020 standard were fabricated by coupling PQD glass powder, demonstrating promising commercial applications of PQD glass in optoelectronic displays.