Abstract: Sustainable synthetic activity involving alternate energy input, and greener reaction medium in aqueous or solvent-free conditions will be synopsized that benefit from recyclable and reusable magnetic nano-catalysts using microwave (MW) irradiation.
Vitamins B₁, B₂, B₁₂, C, and tea or coffee, beet juice and wine polyphenols which function both as reducing and capping agents, provide extremely simple, one-pot, green synthetic methods to bulk quantities of nanomaterials in water. MW hydrothermal process enables the formation of magnetic nanoferrites and micro-pine structured catalysts are obtainable from readily available metal salts. Sustainable route to nanoparticles using polyphenols from winery waste, or biodiesel byproduct, glycerol and their applications in catalysis, toxicity and environmental remediation will be highlighted. The utility of nano-catalysts (Pd, Au, Ag, Ni, Ru, Ce, Cu etc.) immobilized on biodegradable and recyclable supports e.g. cellulose and chitosan or on magnetic ferrites via ligands such as dopamine or glutathione will be presented. The efficacy of heterogenized bimetallic Ag-Pd nanoparticles on graphitic carbon nitride (AgPd@g-C₃N₄) will be emphasized illustrated by upgrading of biofuel via hydrodeoxygenation of vanillin under visible light irradiation using formic acid as a hydrogen source. Photocatalytic C-H activation using VO@g-C₃N₄ catalyst for direct oxidative estrification of alcohols, oxygen insertion reaction in hydrocarbons and selective oxidation of alcohols will be described using visible light as the source of energy. The approach fulfils most of Green Chemistry Principles while producing functional chemicals with extreme level of waste minimization.

Keywords: Green Chemistry; Sustainable Nanomaterials; Magnetic Nano-Catalysts; Microwave Irradiation; Graphitic Carbon Nitrides; Photocatalysis; Biomass Utilization