Green synthesis of metal oxide nanoparticles, and their various applications

Bio-synthesized metal oxide (MeO) nanoparticles (NPs) have triggered a huge global research interest owing to their advancement and various environmental remediation, personal care products, medical, energy, sensing, and water treatment applications. They demonstrate developing assets in various industries, remarkably with their heightened physicochemical, optical, mechanical, and electronic attributes. The physical and chemical routes have been a sticking point in the production of MeO NPs, owing to the natural and environmental risks linked with utilizing these approaches. The growth of MeO NPs production via the biologic method employing plants and microorganisms as a precursor material for metal-ions (MIs) reduction and stabilization has been the focus of research scientists in recent years. Hence, in this review, a comprehensive brief of the bio-synthesis approaches using plant extracts (PEs) and microorganism components for MeO NPs production as well as the various factors affecting the bio-production of MeO NPs, their various applications and their toxicity were considered.