Direct photoinduced synthesis of lead halide perovskite nanocrystals and nanocomposites

All-inorganic CsPbX3 (X = Cl, Br, and I) perovskite nanocrystals (PeNCs) and nanocomposites have shown great promise in optoelectronics and photovoltaics. However, it remains notoriously difficult to control over perovskite nanocomposites at a single particle level. Herein, we report a unique photoinduced method for the controlled synthesis of CsPbX3 PeNCs and nanocomposites based on the light-triggered breakage of the covalent carbon-halogen bond of haloalkanes. The use of molecular haloalkanes as unreactive halide source provides a mild reaction condition, which enables in situ confined growth of CsPbX3 PeNCs in mesoporous nanospheres such as silica with well-defined morphology. As a result, a variety of multifunctional perovskite nanocomposites can be achieved through photoinduced confined growth of PeNCs in mesoporous silica coated nanoparticles. These findings provide a general approach for synthesizing CsPbX3 PeNCs and nanocomposites, which may open up new opportunities for perovskite-based material or device engineering towards versatile applications.