Metallic oxide nanoparticles: state of the art in biogenic syntheses and their mechanisms.

This review presents the syntheses and characterizations of size and morphology, as well as the mechanistic aspects, of metallic oxide nanoparticles synthesized by biogenic processes. Furthermore, the importance of their biogenic synthesis is compared with chemical synthesis, and their applications are discussed from the ecological and environmental view points. To our best knowledge, this review presents for the first time the synthesis of several biogenic oxide nanoparticles, with great applications under the perspective of cost effective and eco-friendly points of view.