An Enclosed Encapsulation Strategy toward Stable Perovskite Quantum Dots: Structure, Lead Immobilization, and Backlight Display Applications

Lead halide perovskite quantum dots have drawn great attention in the wide-color gamut display area. However, their poor stability restricts their practical application as well as the leakage of a toxic lead element. In this study, an enclosed encapsulation strategy is adopted to form CsPbBr₃ quantum dots embedded in the channels of molecular sieve SBA-15 with SiO₂ outer layer as enclosing protection (denoted as CsPbBr₃@SBA-15@SiO₂), which is achieved through a facile solid-state sintering method with post-treatment. The stability of perovskite quantum dots is enhanced remarkably, of which the emission intently after immersion in water for two months can remain over 95% of the initial value. Efficient lead leakage is achieved simultaneously. The improvement mechanisms were elucidated via the micro- and spectral viewpoints. A wide color gamut of 114% NTSC is demonstrated based on the obtained green emitter. This study could provide new insights into designing stable and environmentally sustainable perovskite quantum dots and promote their applications.