A Review on Structures and Methods of Synthesis of ZnO NPs with a Focus on Cost-Effectiveness and Availability for Various Applications

Nanotechnology focuses on the creation and application of materials at the nanoscale, where nanoparticles exhibit unique physicochemical properties due to their high surface area-to-volume ratio. Among these, zinc oxide (ZnO) based nanomaterials have gained significant attention due to the abundance of zinc and the ease of integrating ZnO into various nanostructures. Since the advent of nanoscience, ZnO has been widely utilized in fuel cells, solar cells, water purification, and biomedical applications, existing in diverse forms such as nanoparticles, nanowires, and nanofibers. ZnO nanoparticles, in particular, have attracted extensive research interest due to their wide bandgap and exceptional exciton binding energy, which contribute to their enhanced optical, electronic, and catalytic properties. Compared to their bulk counterparts, ZnO nanoparticles offer superior performance while reducing material consumption and production costs. This review provides a comprehensive analysis of the synthesis techniques, structural characteristics, and diverse applications of ZnO nanoparticles, highlighting recent advancements and future research directions in this rapidly evolving field.