Authors: Peng Wang, Ke Yang, Lingcai Zhang, Xingliang Dai, Zhizhen Ye, Haiping He, Chao Fan
Published: 2025-05-30
Source: Full article
AbstractPerovskite quantum dots (QDs) hold promise for next‐generation display applications but suffer from stability challenges, particularly thermal‐ and light‐induced photoluminescence (PL) quenching. Here, a fluoride post‐treatment (FPT) strategy is developed to address this challenge for CsPbBr3 QDs embedded in silica matrices (CsPbBr3/silica composites). The FPT enables epitaxial growth of BaF2 shells on CsPbBr3 surfaces via thermally driven fluoride ion diffusion, which passivates surfaces and suppresses thermal‐ and light‐induced defects in CsPbBr3. The FPT‐treated CsPbBr3/silica composites exhibit a high PL quantum yield of 94.5%, a complete PL recovery after a thermal cycling (up to 403 K), and retain 95.6% of their initial PL intensity after 1055 h with intense blue light irradiation (350 mW cm−2). To the best of the knowledge, these FPT‐treated CsPbBr3/silica composites represent the most stable CsPbBr3 emitters under light aging. Theoretical calculations reveal that the BaF2 shells elevate the formation energy of bromine vacancies and anchor [PbBr6] octahedra in CsPbBr3, thereby inhibiting defect generation. A liquid crystal display (LCD) equipped with these composites achieves a 120% national television system committee color gamut. This work provides a robust route to stabilize CsPbBr3 QDs for high‐performance LCD applications.