Combustion synthesis of graphene oxide–TiO2 hybrid materials for photodegradation of methyl orange

Abstract

Graphene oxide (GO)–TiO2 hybrid materials with enhanced photocatalytic properties were synthesized by a one-step combustion method using urea and titanyl nitrate as the fuel and oxidizer, respectively. During the synthesis procedure, the precursors containing GO, fuel, and oxidizer were maintained at different combustion temperatures (300–450°C) for 10min to ignite the combustion reaction. The effects of combustion temperatures on the weight loss, chemical status and photocatalytic properties were studied by thermogravimetry and differential scanning calorimetry, X-ray photoelectron spectroscopy, Raman, and photoluminescence. GO in the GO–TiO2 hybrids were not oxidized, but thermally reduced by decomposition of partial oxygen-containing groups. Meantime, the nitrogen doping of GO was achieved. Compared to the neat TiO2 obtained at same condition, GO–TiO2 hybrid obtained at 350°C exhibited enhanced photodegradation performance, which is attributed to the effective photo-generated electron transferring from TiO2 to partially reduced GO, which confirmed by the photoluminescence quenching of TiO2.