Synthesis and characterisation of neodymium doped-zinc oxide-graphene oxide nanocomposite as a highly efficient photocatalyst for enhanced degradation of indigo carmine in water under simulated solar light

A nanocomposite (Nd-ZnO-GO) with enhanced photocatalytic properties was synthesized by co-precipitation method. The structures, morphologies and photocatalytic activities of the nanocomposite were studied using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and ultraviolet-visible spectroscopy. Indigo carmine (IC) dye was used to evaluate the photocatalytic performance of the nanocomposite under simulated solar light. The photocatalytic results indicate that the nanocomposite [Nd-ZnO-GO (0.3 % Nd)] showed good photocatalytic activity and could be considered as a promising photocatalyst for treatment of organic pollutant in water. The high and efficient photocatalytic degradation of IC solution by the nanocomposite [Nd-ZnO-GO (0.3 % Nd)] is attributed to improve absorbance in the visible region and the separation of charge carriers due the combined effect of Nd and GO. Analysis from Total organic carbon (TOC) displayed a higher degree of complete mineralisation of IC (TOC removal of 76 %) which decreases the formation of possible toxic degradation by-products. The stability of Nd-ZnO-GO (0.3 % Nd) nanocomposite caused it to be reused for five times reaching 83.0 % degradation efficiency after the five cycles.