Ultra‐Stable CsPbX<sub>3</sub>@Pyrophosphate Nanoparticles in Water over One Year
Qixuan Zhong, Xuchun Wang, Mingyu Chu, Yinghua Qiu, Di Yang, Tsun‐Kong Sham, Jinxing Chen, Lu Wang, Muhan Cao, Qiao Zhang
Abstract
Abstract All‐inorganic lead halide perovskite (CsPb X 3 , X = Cl, Br, I, or their mixture) nanocrystals (NCs) have achieved inspiring advancements in optoelectronic fields but still suffer from poor durability when exposed to environmental stimuli such as water, irradiation and heat. Herein, a strategy of employing pyrophosphate as the inert shell for CsPbX 3 NCs is reported. The strong binding between pyrophosphate and CsPbBr 3 surface can stabilize the perovskite structure well. The as‐obtained core@shell CsPbBr 3 @NH 4 AlP 2 O 7 NCs exhibit impressive stability against water and maintain the initial optical properties with negligible change in 400 days. Furthermore, significant improvement of irradiation/thermal resistance is realized due to the protecting role of pyrophosphate. The NCs can retain 100% and ≈90% of the original PL after hundreds of heating/cooling cycles and several hundred hours of UV light irradiation, respectively. As a result, the core@shell products can be directly used for high‐resolution inkjet printing, enabling the printed fluorescent information to be resistant under harsh environmental conditions. This work provides a promising way for the synthesis of highly stable encapsulated perovskite NCs and demonstrates a great potential in practical applications.