Optical and structural properties of CsPbBr₃ perovskite quantum dots/PFO polymer composite thin films

The aim of this study is to investigate the optical and structural properties of polymer/perovskite quantum dots (QDs) composite thin films and estimate the applicability of using these blends as active materials in photonic devices. A solution has been utilized, which is processed based on conjugated polymer and perovskite QDs composite films. The incorporation of CsPbBr₃ QDs, with various weight ratios, influences the structure of the thin films, as proven by several techniques. The results of the study showed that the surface of the poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO)/CsPbBr₃ thin films improved, when compared to that of the pristine CsPbBr₃ thin film. The increase in the steepness parameter and decrease in both the energy gaps and Urbach tail, upon the increment of CsPbBr₃ QDs, can be attributed to the decrease in the localized density of electronic states within the forbidden band gap of the hybrids. The overlap between the absorption spectrum of PFO and emission spectrum of CsPbBr₃ QDs, and the enhancement in the emission peak of CsPbBr₃ in the blends, confirmed the efficient non-radiative energy transfer between them.