Sensitization of CdS nanoparticles onto reduced graphene oxide (RGO) fabricated by chemical bath deposition method for effective removal of Cr(VI)

Abstract

RGO (Reduced Graphene Oxide)-CdS composites were successfully synthesized by chemical bath deposition (CBD) method onto soda lime glass substrate at low temperature (70 degrees C). Their structural, optical and morphological properties were studied using X-ray diffraction, UV-Vis spectrophotometer, Raman spectroscopy, Brunauer-Emmett-Teller, Field emission scanning electron microscope and transmission electron microscope. It is clearly seen that spherically shaped CdS nanoparticles with an average diameter 30 nm are uniformly coated over the entire graphene sheet. Further, synthesized CdS nanoparticles and RGO-CdS nanocomposites were investigated for the reduction of Cr(VI) under visible light. The photocatalytic results show that photodegradation rate of RGO-CdS composites is two times higher than that of CdS nanoparticles toward reduction of Cr(VI). The improved photocatalytic performance by combining RGO with CdS nanoparticles, is attributed to its increased specific surface area (47.44 m(2) g(-1)), efficient transportation of photoelectrons and improved absorbance of CdS nanoparticles. Therefore, it was found that RGO in RGO-CdS composites makes a significant impact on photocatalytic activity toward reduction of Cr(VI), making an excellent candidate for water refiner. (C) 2013 Elsevier B.V. All rights reserved.