Review on green biomass-synthesized metallic nanoparticles and composites and their photocatalytic water purification applications: Progress and perspectives

In recent years, the use of biomass for the cost-effective synthesis of nanoparticles has emerged as a promising green technology. Because of their remarkable properties, such as tunable surface plasmon resonance characteristics and high surface areas, bio-synthesised nanomaterials are receiving more scientific and academic attention for their use in various application sectors, especially as catalysts in environmental remediation. Green synthesized nanomaterial's can efficiently contribute to the degradation of a wide range of organic pollutants, including dyes, into harmless by-products. These particles have a cure for recalcitrant organic and inorganic pollutants due to their photocatalytic properties, which largely depend on the production of reactive oxygen species under sunlight or UV illumination. This comprehensive review systematically covers up-to-date knowledge on recent developments in the green synthesis of nanoparticles and composites using plants and microorganisms, unravels underlying mechanisms, and highlights their application areas. It then provides detailed information on their applications in the degradation of potentially toxic organic dyes and the removal of other emerging pollutants, including heavy metals and antibiotics. Finally, the current challenges and perspectives of this technology for future applications are discussed.