One-Pot Synthesis of Highly Stable CsPbBr3@SiO2 Core–Shell Nanoparticles

The practical applications of CsPbX 3 nanocrystals (NCs) have been limited by their poor stability. Although much effort has been devoted to making core–shell nanostructures to enhance the stability of CsPbX 3 NCs, it is still very difficult to coat CsPbX 3 NCs with another material on a single-particle level. In this work, we report a facile one-pot approach to synthesize CsPbBr 3 @SiO 2 core–shell nanoparticles (NPs), in which each core–shell NP has only one CsPbBr 3 NC. The formation process has been carefully monitored. It has been found that the formation rates, determined by reaction temperature, precursor species, pH value, etc., of both CsPbBr 3 and SiO 2 are critical for the successful preparation of core–shell NPs. Thanks to the protection of SiO 2 shell, the product shows much higher long-term stability in humid air and enhanced stability against ultrasonication treatment in water than that of naked CsPbBr 3 NCs. This work not only provides a robust method for the preparation of core–shell nanostructures but also sheds some light on the stabilization and applications of CsPbX 3 NCs.