Phenanthroline-Capped Cs₃Cu₂Cl₅ Perovskite Quantum Dots for Fluorescence Sensing of Tebuconazole Fungicide

Tebuconazole (TEB) is used as a fungicide to control various crops; however, it poses a risk to humans, indicating an urgent need to develop a quite specific and sensitive fluorescent probe for TEB detection. The detection of TEB using lead-free halide perovskites has not been reported to date. This paper reports the successful synthesis of lead-free green emissive phenanthroline stabilized Cs3Cu2Cl5 perovskite quantum dots (Phen@Cs3Cu2Cl5 PQDs) with a fluorescence quantum yield of 31.07%. The as-prepared Phen@Cs3Cu2Cl5 PQDs were utilized as a sensing probe for the detection of TEB. The addition of TEB into a Phen@Cs3Cu2Cl5 PQDs solution significantly reduced the green fluorescence of Phen@Cs3Cu2Cl5 PQDs at 515 nm when excited at 300 nm, displaying a good linear concentration range of 0.01–25 μM for TEB detection with a detection limit of 3.44 nM. The developed method exhibited good recoveries in the range of 98.06–99.39% with a relative standard deviation (RSD) of 0.26–1.23% and of 98.57–99.28% with an RSD of 0.71–1.95% for the spiked cabbage and rice samples, respectively. Therefore, the proposed Phen@Cs3Cu2Cl5 PQDs can serve as efficient fluorometric sensors for real-time detection of TEB in food samples.