Tuning the optical properties of SnO2 by doping Cu2+ for enhancing solar irradiated photodegradation of dye effluents and underlying mechanism

Abstract

Water pollution due to industrial dye effluents is a major concern to society. To tackle with this situation, Sn1-xCuxO2 (x = 0, 0.1 & 0.2) nanocomposites were synthesized by co– precipitation technique. The phase structure, morphology and optical properties of prepared nanocomposites were determined using XRD, FTIR, SEM-EDAX with elemental mapping, electrical resistivity, UV– VIS- DRS, Photoluminescence and XPS methods. Sn1-xCuxO2 crystallizes in tetragonal structure without phase segregation up to x = 0. 2. As compared to pristine SnO2, Sn1-xCuxO2 exhibit red shift in the visible region. XPS study confirm the presence of Cu2+ and Sn4+ ions in Sn1-xCuxO2. Visible light harvesting efficiency was evaluated by photodegradation of Amido Black dye under natural sunlight. 67 % degradation was observed with SnO2 in 60 min time which enhances to 100 % with Cu doping. Analysis of degradation product and the formation of reactive OH. radical was checked by fluorescence technique using terephthalic acid. Sn1-xCuxO2 composites also exhibit antibacterial action towards gram positive and gram-negative bacteria thereby preventing spread of water borne diseases.