Precision-Engineered CsPbBr3 Quantum Dots with Encapsulation and Tunable Size Exhibiting Temperature-Responsive Luminescence for Emerging Sensors

In this work, CsPbBr3 perovskite quantum dots (QDs) were synthesised by hot injection, with reaction time controlling nanocrystal size and emission from 493 to 515 nm. Temperature-dependent photoluminescence (23–80 °C) showed decreasing intensity but stable peak position. Embedding QDs in PMMA and PVK revealed polymer-dependent thermal behaviour: insulating PMMA preserved radiative recombination and gave stable, reproducible quenching, while semiconducting PVK introduced interfacial charge transfer, enhancing thermal sensitivity. The results establish CsPbBr3 QD–polymer composites as tunable temperature-sensitive platforms for optical sensing.