Synthesis and optical properties of perovskite nanocrystals in glass with cationic substitution.

This article systematically investigates the incorporation of cadmium ions (Cd²⁺) into CsPb₁–ₓCdₓBr₃ perovskite nanocrystals (NCs) formed within fluorophosphate (FP) glass and its effects on their structural and photoluminescence (PL) properties. X-ray diffraction and transmission electron microscopy confirm successful Cd²⁺ incorporation, causing lattice contraction and a corresponding blue shift in the PL band from 2.42 to 2.68 eV, with a significant decrease in PL quantum yield (QY) from 85% to as low as 4% at high Cd concentrations. Low-temperature PL measurements reveal the emergence of deep acceptor trap states induced by Cd doping, which degrade the defect tolerance of CsPbBr₃ NCs and reduce optoelectronic performance. The study highlights that while Cd substitution enables bandgap tuning toward blue emission, it simultaneously introduces defect states that limit luminescence efficiency, contrasting with some prior reports of improved PL QY upon Cd doping in colloidal systems.