In situ biogenic synthesis of CuO nanoparticles over graphene oxide: A potential nanohybrid for water treatment

The development of environmental friendly and benign strategies for the purification of dye polluted water is a growing challenge. To this end, Solanum americanum functionalized copper oxide-graphene oxide (CuOSA/GO) nanohybrid were prepared by an efficient, eco-friendly, and economical green procedure by using Solanum americanum leaf extract as a reducing agent (i.e., for the reduction of metal salt) as well as the stabilizing agent. The formation of CuOSA/GO nanohybrid was confirmed by using various spectroscopic and microscopic techniques. Microsphere shaped clusters of CuOSA were shown to be coated over GO surface confirmed via SEM while the crystallite size of 5.48 nm was calculated from powder x-ray diffraction data., i.e., Methyl blue (MB) (98% ± 6.9 removals in 60 min), Methyl green (MG) (87% ± 6.62 removals in 60 min), Methyl orange (MO) (69% ± 7.02 removal in 60 min), Methyl violet (MV) (63% ± 6.97 removals in 60 min) and Rhodamine B (RB) (36% ± 6.98 removals in 60 min) with apparent rate constants of 0.038, 0.034, 0.019, 0.016 and 0.007 min-1 respectively. The enhanced rate was obtained due to the large surface area provided by the GO and the synergetic effect. The green synthesis approach and photocatalytic efficiency make the CuOSA/GO nanohybrid a promising candidate for the purification of dye polluted water via photocatalytic oxidation method.