Selective fluorescence sensor for Fe³⁺ based on in situ synthesis of CsSnCl₃ perovskite quantum dots with bone gelatin

The sensors of perovskite quantum dots (QDs) based on Pb have gained more popularity in sensing applications. However, severely restricts any more practical uses because of the toxicity of Pb. In this study, we created an efficient in situ method to make bone gelatin-CsSnCl3 QDs in 1-allyl-3-methyl imidazole chloride ([AMIM]Cl), which were both very stable and environmentally benign. As a consequence, the relative photoluminescence intensity of bone gelatin-CsSnCl3 QDs retained over 96% in water for 55 h, showing negligible degradation. The oxidation of Sn2+ in CsSnCl3 QDs was effectively prevented. The interaction strength of carboxyl, amino, and long molecule chains in bone gelatin and CsSnCl3 QDs was evaluated; the strongest binding force is between -COO- and CsSnCl3 QDs; and the weakest is between long molecular chains and CsSnCl3 QDs. Furthermore, bone gelatin-CsSnCl3 QDs demonstrated good selectivity and a low detection limit for Fe3+ in aqueous solution (150 mu M). The findings indicate that bone gelatin-CsSnCl3 QDs have a bright future in the realm of fluorescence sensing.