Synthesis of Solanum nigrum mediated copper oxide nanoparticles and their photocatalytic dye degradation studies

The discharge of dyes in industrial textile effluent is a concerning environmental threat. Although dyes contribute only a minute part of the effluent waste volume, factors such as high visibility, complex aromatic structure, impact on human health and aquatic life necessitated removal of dye. Photocatalytic dye degradation using biologically synthesized nanoparticles provides a sustainable method for the degradation of environmental pollutants when compared to physico-chemical methods. Copper oxide nanoparticles (CuONPs) have recently gained attention owing to the large surface area, and ability to act as photocatalysts unlike other metal oxides which require the need for doping. Solanum nigrum (Black Nightshade) plant extracts that possess anticancer, diuretic, antioxidant, antipyretic and anti-inflammatory activities has been used in the present study to prepare copper oxide nanoparticles and characterized using absorption spectroscopy, EDX, XRD, TEM and FTIR analyses. The degradation efficiency of the synthesized nanoparticles have been demonstrated for a wide range of industrial dyes like Methyl Orange (MO), Methylene Blue (MB), Safranin O, Congo Red (CR) and Coomassie Brilliant Blue R-250 (CBB). In addition, the effectiveness of the copper oxide nanoparticles in removing toxicity from dye mixture and contaminated textile effluent has also been evaluated. (paper)