Research on the photoluminescence properties of Cu-doped perovskite CsPbClquantum dots

CsPbX(X = Cl, Br, and I) quantum dots (QDs) and Cu-doped CsPbClQDs with different Cu-to-Pb molar ratios were synthesizedviaa solvent-based thermal synthesis method. The photoluminescence (PL) properties of these Cu-doped CsPbClQDs were also investigated in this study. The results showed that with the increase in the Clconcentration the surface defects of CsPb(Cl/Br)QDs increased, which resulted in an increase in the non-radiative recombination of excitons and weakened the PL intensity. Moreover, Cu-doped CsPbClQDs maintained the cubic crystal structure of the initial phases. Owing to the doping of Cuions, the surface defects of CsPbClQDs were effectively eliminated, which facilitated the excitonic recombinationviaa radiative pathway. The PL quantum yields (PLQYs) of Cu-doped CsPbClQDs were increased to 51%, showing great photostability. From the results, it is believed that Cu:CsPbClQDs can be widely used in optoelectronic devices.