Highly Efficient Degradation of Tetracycline Hydrochloride Using Monodisperse CuGaS₂ Quantum Dots Under UV-LED

CuGaS2 quantum dots (QDs) with uniform size distribution and monodispersion were successfully synthesized by using the hot injection method. Their microstructure, energy band structure, optical properties, and photocatalytic degradation activity were systematically studied. When the reaction temperature was between 180 and 260 °C, the prepared CuGaS2 QDs exhibited a single chalcopyrite structure. The diameter increased from 5 to 18 nm, while the optical band gap decreased from 3.11 to 2.64 eV. Notably, CuGaS2 QDs synthesized at an optimal temperature of 220 °C, with a mean particle size of 8 nm, demonstrated remarkable photocatalytic activity. Under 60 min of UV-LED irradiation at 365 nm, degradation rates of 93.76% for tetracycline hydrochloride (TCH) and 22.45% for methyl orange (MO) were achieved. These results indicate the tremendous potential of CuGaS2 for water pollution remediation.