This book explores recent developments in the design and synthesis of greener nanomaterials and their eco-friendly utilization at the industrial scale. It defines key material descriptors required for their successful employment in different applications and discusses their cost-effective synthesis from natural extracts. The text provides comprehensive links between the design/fabrication of nanoparticles and their catalytic performance (activity, selectivity, and stability) in various applications. The topics covered include photocatalysis, wastewater treatment, environmental ecology, medical biology, biotechnology, sensors, cosmetics, remediation, energy, and phytoformulation.