Photocatalytic evaluation of RGO/TiO(2)NWs/Pd-Ag nanocomposite as an improved catalyst for efficient dye degradation

In this work RGO/TiO(2)NWs/Pd-Ag nanocomposite was prepared by using a combination of hydrothermal and photo-deposition methods. The properties of all prepared products were evaluated by using SEM, XRD, DRS, FT-IR, EDS, BET, TEM, TGA and ICP-OES analysis. Nanodimension structure of all samples was confirmed by TEM and SEM results. The calculated band gap values which were obtained by using DRS technique, suggested that Gr/TiO(2)NWs/Pd-Ag nanocomposites have a semiconductor behavior with a direct band-gap value of 2.95 eV. The amount of loaded graphene in the nanocomposite was evaluated by using TGA analysis. The degradation of rhodamine B and methylene blue by TiO2-NWs and RGO/ TiO(2)NWs/Pd-Ag nanocomposites were compared under UV light irradiation in similar conditions. The observations confirmed that the RGO/TiO(2)NWs/Pd-Ag nanocomposite have high photocatalytic performance toward both of pollutants owning to the much higher available surface area of TiO2 nanowires, the unique synergic effect of Pd and Ag species and high electric transport property of the graphene structure. The product synthesis procedure has valuable advantages like high surface area photocatalyst, facile photodeposition of silver and palladium on the TiO2 surface, and simple conversion of graphene oxide (GO) to reduced graphene oxide (RGO) during the hydrothermal process without using strong reducing agents, which can be a promising route for preparing various types of high active carbon based nanocomposite photocatalyst. (C) 2018 Elsevier B.V. All rights reserved.