Recent Trends and Advancement Toward Phyto-mediated Fabrication of Noble Metallic Nanomaterials: Focus on Silver, Gold, Platinum, and Palladium

Abstract

Globally, nanotechnology has been materialized as a novel field of modern science in recent years owing to its exceptional properties with widespread applications. This field acts as an innovative platform for the tailoring of materials like metals at the atomic level so as to achieve exceptionally small size as well as large surface to volume ratio with unique properties, comparatively distinct from their bulk form that can be appropriately manipulated for the desired uses. For instance, nanomaterials (NMs) of gold, silver, platinum, as well as palladium are extensively exploited in fast-moving consumer goods like shampoos, detergents, etc. The fabrication of metal NMs can be carried out using physical, chemical, and green chemistry approaches. Metal NMs fabricated through physical and chemical approaches are not only costly and hazardous for the biotic and abiotic components of the ecosystem but also depict limitations related to stability, particle agglomeration, particle size heterogeneity, etc., over green chemistry approaches. The inexpensive cultivation, safety, short fabrication period, as well as ability to scale up enable plants as an eye-catching platform toward the fabrication of metallic NMs over other biological systems such as fungi, bacteria, etc. In addition, diverse biomolecules in plants serve as reducing, stabilizing, and capping agents and therefore enhance the rate of reduction as well as stabilization of fabricated NMs. Nevertheless, because of rich biodiversity of plant systems, their potential utilization for the fabrication of metal NMs is yet to be completely discovered. Overall, the present chapter provides an overview on the recent trends and advances toward plants’ mediated formation of noble metallic NMs, i.e., silver, gold, platinum, and palladium, with their possible mechanism of fabrication including potential applications.