Experimental Study on Green Synthesis of Copper Nanoparticles and Its Utilization for Degradation of Organic Dye

Metal and metal oxide nanoparticles are widely used to remove organic dyes from wastewater due to their higher surface area, high adsorption capacity, chemical stability, and photocatalytic activity. In present work, Azadirachta indica (neem) leaf extract was used as a reducing and capping agent for the green synthesis of copper nanoparticles (CuNPs) with homogeneous precipitation process. The developed green method of Azadirachta indica leaves extract was found to be simple, environment-friendly, and cost-effective as compared to existing toxic reducing agents. Synthesized CuNPs using green route were characterized by UV–visible spectroscopy, Fourier Transform Infrared spectroscopy (FTIR), and Scanning Electron Microscopy (SEM) analysis. UV–visible spectroscopy analysis showed characteristics absorption peaks at 800 nm confirming the formation of copper nanoparticles. FTIR spectra exhibited the presence of bioactive molecules in leaf extract which are responsible for the reduction of copper ions to CuNPs. Moreover, Scanning Electron Microscopic (SEM) analysis also revealed that synthesized CuNPs were in spherical shape with average size of particles ranging between 50 and 70 nm. Further, this study reports utilization of biosynthesized CuNPs for degradation of organic dye, namely, methylene blue dye from wastewater samples under sunlight. Result analysis revealed that approximately 60% of degradation of Methylene blue dye was observed within 120 min using green synthesized copper nanoparticles that exhibit good photocatalytic activity. This study demonstrates that green synthesized copper nanoparticles can be effectively used for removal of hazardous dye from industrial wastewater which contributes to cost-effective, environmental, and sustainable processes.