Anti-bacterial activity Antibacterial properties Antibacterial tests Blue emission bands Energy gap Fourier transform infrared spectroscopy II-VI semiconductors Inhibition zones Morphology Nanoparticles Optical properties Particle size analysis Sol-gel process Sol-gel technique Sol-gels Synthesis (chemical) Ultraviolet visible analysis X ray diffraction Zinc oxide Zinc oxide nanoparticles ZnO nanoparticles antibacterial test morphology optical properties pH sol-gel technique