Investigation of amino-grafted TiO2/reduced graphene oxide hybrids as a novel photocatalyst used for decomposition of selected organic dyes

Abstract

A novel type of photocatalyst - hybrids of amino-grafted titania and reduced graphene oxide - was synthesized by a hydrothermal method. The hybrids were comprehensively analyzed, including determination of their morphology (TEM), porous structure parameters (low-temperature N₂ sorption) and crystalline structure (XRD). Additionally, to confirm the effective bonding of the amino-grafted titania and reduced graphene oxide, Raman and X-ray photoelectron spectroscopy (XPS) were used, in addition to elemental analysis. The key stage of the research was an evaluation of the photocatalytic activity of the synthesized hybrid photocatalysts with respect to the decomposition of C.I. Basic Blue 9 and C.I. Basic Red 1 dyes. It was found that the amino-grafted titania/reduced graphene oxide hybrids exhibited better photocatalytic activity in the degradation of C.I. Basic Blue 9 and C.I. Basic Red 1 than amino-grafted TiO₂ alone. The high efficiency of dye decomposition can be attributed to the higher BET surface area and good separation of photogenerated electrons and holes offered by graphene oxide.

Keywords: Amino-grafted titania/reduced graphene oxide hybrid; Graphene oxide; Hydrothermal synthesis; Photocatalysis; Sol-gel method; Titanium dioxide.