Spectral regulation of Sn/Br-co-doped perovskite nanocrystalline glass

Abstract

The Sn/Br co-doped CsPbI₃ borosilicate glass was synthesized using the melt quenching method. It is revealed by transmission electron microscopy (TEM) and X-ray diffraction (XRD) results that Sn and Br are incorporated into the B-site and X-site of the nanocrystals, respectively Furthermore, it is particularly noteworthy that as the doping content rises, Sn and Br interact with Cs to generate two distinct types of nanocrystals (NCs), namely CsPbBr₃ and Cs (SnBr₃), which coexist with CsPbI₃ within the glass matrix. This finding is further substantiated by the data obtained from fluorescence microscopy. In correspondence with the structural alterations, as the doping concentration rises, a blue-shift phenomenon is initially manifested in the emission spectrum of the sample. After a certain concentration is reached, the superposition of different emission peaks begins to be shown by the sample, which stems from the co-existence of mixed-phase NCs within the system as is revealed by XRD and TEM. A highly effective approach for the spectral regulation of CsPbI₃ glass is furnished by the incorporation of Sn and Br ions. Not only can it enable the shift of monochromatic spectra, but it also holds the potential to render a single material capable of white-light emission. Meanwhile, the popularization and application of this NCs glass are also supported by excellent physical and chemical stability.