Encapsulation of Pb-Free CsSnCl3 Perovskite Nanocrystals with Bone Gelatin: Enhanced Stability and Application in Fe3+ Sensing

The toxicity of the Pb element limits the large-scale applicationof inorganic cesium-lead halide (CsPbX3, with X = Cl, Br, and I) perovskitenanocrystals (NCs). Pb-free cesium-tin halide (CsSnX3) NCs have emerged asa viable alternative because of its excellent photoelectric conversion efficiency.However, the applications are hampered by its poor stability and lowphotoluminescence quantum yield (PLQY). In this study, extraordinarily stableCsSnCl3NCs were prepared by exploiting bone gelatin as surface cappingagents, which retain 95% of the photoluminescence intensity in water for 55 h.Additionally, after bone gelatin encapsulation, the PLQY of CsSnCl3NCs wasfound to increase from 2.17% to 3.13% for the uncapped counterparts becauseof an improved radiative recombination rate. With such remarkable opticalproperties of the bone gelatin-CsSnCl3NCs, metal ions like Fe3+in aqueoussolutions can be readily detected and monitored, signifying the potentialapplication of such stable bone gelatin-CsSnCl3NCs in the development offluorescence sensors and detectors

Automated summary

Extraordinarily stable CsSnCl3 nanocrystals were prepared by exploiting bone gelatin as capping agents, leading to an improved photoluminescence quantum yield. These nanocrystals can be used for detecting metal ions, indicating their potential application in fluorescence sensors and detectors.