Green synthesis and methodologies of nanomaterials: State of the art

Nanomaterials possess remarkable properties that make them increasingly essential products. Traditionally, the synthesis of nanomaterials was based on chemical and physical procedures that involved the use of expensive and hazardous substances. Nowadays, their fabrication is moving towards “green synthesis” methodologies centered on nontoxic reaction components and mild reaction conditions, becoming eco-friendly and reliable solutions. Natural sources such as plants, microorganisms, polysaccharides, bio-wastes, or biomolecules have been used as economic forms of reducing and capping agents during nanomaterials synthesis. A wide range of metal, metal oxide, and nonmetal nanoparticles have been produced by green synthesis. The success of obtaining nanomaterials with good shape, size, and function by green methodologies depends on the reaction parameters, like temperature, pH, and time. Green synthesized nanoparticles are nontoxic and highly biocompatible with broad range of applications. They are widely used as anticancer agents, antimicrobials, sensors, pesticides, dye removal, among others, in the areas of biomedicine, agriculture and environmental care. This chapter explores and presents the most recent nanoparticles formed by green synthesis, the two principal green synthesis mediators, and their main applications.