Post-synthesis gamma radiation effects on the optical and morphological properties of CsPbBr3 perovskite nanocrystals

Abstract

CsPbBr₃ nanocrystals (NCs) synthesis followed through the simple, cost effective and, room temperature (RT) method of ligand assisted re-precipitation (LARP). The CsPbBr₃ NCs exposed to gamma radiation in six different doses of 4, 7, 10, 30, 70, and 100 kGy for study the radiation effect on NCs. UV-Vis, photoluminescence (PL), and bandgap spectra were analyzed to evaluate the optical characteristics of the NCs. X-ray diffraction (XRD) and FESEM analyses were performed to study the crystal structure and morphological alterations of the NCs under gamma radiation doses. Dynamic light scattering (DLS) analysis was used to investigate the size distribution of colloidal NCs particles. By increasing the radiation dose absorption and PL intensity reduced to 37% of first sample for 4 kGy and 3% for 100 kGy, and increased bandgap, from 2.3 eV to 2.5 eV, correspondingly enlarged grain size from 26 nm for unirradiated sample to 50, 61 and 59 nm for 4, 30 and 100 kGy irradiated samples respectively. XRD patterns showed a gradual decrease in crystallinity and a significant increase in particle size. The results revealed significant structural and optical changes and control over the NCs, which render them potential candidates for applications in sensors, optoelectronic devices (e.g., LEDs and photovoltaic cells), and radiation detection.