Structural and defect-related optical characteristics of Viola odorata extract mediated ZnO

We report crystallographic and defect-related optical characteristics of ZnO nanoparticles (NPs) generated by phytoextract mediated approach using Viola Odorata. The crystallographic analysis using XRD data validated the wurtzite crystal structure of ZnO. To find the crystallite size and deformation in prepared ZnO-NPs, the XRD data was analyzed using Williamson-Hall (W-H) methods considering uniform strain model. In addition, the photoluminescence of the prepared ZnO-NPs has been explored to identify the defect related emission in the visible region. The presence of native defects such as zinc interstitials (emissions at 2.98 eV and 2.79 eV) and oxygen vacancies (emissions at 2.57 eV) is shown by photoluminescence spectrum. Finally, the methylene blue (MB) degradation was examined for the produced ZnO-NPs' photocatalytic reaction to solar light irradiation.