Affiliation: | 1. Department of Electrical & Electronics Engineering, Faculty of Engineering, Düzce University, Düzce, Turkey;2. Department of Electrical & Electronics Engineering, Faculty of Engineering, Düzce University, Düzce, Turkey Contribution: Data curation, Formal analysis, Methodology, Validation, Writing - original draft, Writing - review & editing;3. Scientific and Technological Research Laboratory, Düzce University, Düzce, Turkey Contribution: Data curation, Formal analysis, Investigation, Methodology, Validation, Visualization;4. Department of Prosthetics & Orthotics, Faculty of Health Science, Ankara University, Ankara, Turkey Contribution: Methodology, Validation, Visualization, Writing - original draft, Writing - review & editing |
Abstract: | In this study, CuLaSe2 and ZnCuLaSe2 quantum dots (QDs) with a mean size of ~4 nm were synthesized and characterized, and their temperature-dependent photoluminescence (PL) properties were studied in the temperature range from 90 to 300 K for the first time. The results show that the obtained QDs were spherical and revealed excitonic band gaps. The PL intensity for both types of materials decreased when increasing the temperature to 300 K, which was attributed to the nonradiative relaxation and thermal escape mechanisms. As the temperature was increased, the PL linewidths broadened, and PL peak energies were red shifted for both types of QDs due to the exciton–phonon coupling and lattice deformation potential mechanisms. In addition, we found that as the temperature was decreased, the PL spectrum of ZnCuLaSe2 QDs contained two extra components, which could be attributed to the shallow defect sites (low energy peak) and the crystal phase transition process (high energy peak). The spectrum of CuLaSe2 QDs contained one extra component, which could be attributed to the crystal phase transition process. |