Role of Defects in Tailoring the Structural, Optical, and Antibacterial Properties of Y/Cu Co-Doped ZnO Nanoparticles

Abstract The sol–gel technique was employed to create Zn 0.99−x Cu 0.01 Y x O (x = 0.00 to 0.05 with 0.01 increments) nanoparticles, and examined for potential applications in optoelectronics, biomedicine, and sensors. The influence of defects formed during synthesis in Y/Cu doped ZnO nanoparticles on their antibacterial, optical, and structural characteristics was explored. All Y/Cu co-doped ZnO nanoparticles exhibited single-phase structures. The sizes of the Y/Cu co-doped ZnO nanoparticles were observed to range from 2 to 50 nm. UV analysis showed that the reflectance intensities and Eg values of Zn 0.99−x Y x Cu 0.01 O (x = 0.00–0.05) nanoparticles ranged from 69 to 91% and from 3.20 eV to 3.263 eV, respectively. The defect types in Y/Cu co-doped ZnO nanoparticles were examined using photoluminescence (PL) spectra, which revealed ultraviolet emission in addition to a broad band including violet, blue, and red areas, which were ascribed to excitonic and defect-related emissions. The synthesis conditions, as well as the doping components and ratios, had a substantial impact on these emissions. The energy band of Y/Cu co-doped ZnO nanoparticles was computed, and their effects on optical characteristics were examined. A different model was used to compute the refractive index. Gram-positive S. aureus and gram-negative E. coli were utilized to examine the antibacterial properties of Zn 0.99−x Cu 0.01 Y x O nanoparticles.