Synthesis and characterization of Y2O3-reduced graphene oxide nanocomposites for photocatalytic applications

Yittrium oxide (Y2O3)-reduced graphene oxide (rGO) nanocomposite was prepared by a low temperature solution process by mixing different weight ratios of chemically derived rGO and Y2O3. The structural properties of nanocomposite materials have been analyzed by x-ray diffraction. Laser Raman spectroscopic study further confirmed the formation of the nanocomposite materials. The morphology of the nanocomposite has been analyzed by field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) images. From the FE-SEM and TEM images, it was found that the nanocrystals of Y2O3 were interpolated in the graphene sheets. X-ray photoelectron spectroscopy (XPS) analysis confirmed that the rGO has a reasonable amount of C-O groups as the doublet was observed in the C1s spectrum. Moreover, the O1s peak illustrates the doublet peaks which confirms the presence of OH and other functional groups at the surfaces of rGO. Electrochemical behavior of the nanocomposite was studied by cyclic voltammetric studies. The nanocomposite with higher weight percent of rGO shows better photocatalytic performance compared to the samples with low weight percent of rGO. The photocatalytic characteristics of the nanocomposite have been discussed based on the XPS results. The presence of hydroxyl group in the rGO of nanocomposites increases the OH radical formation and suppresses the recombination of excitons, which is responsible for the rapid decomposition of dye molecules.