Sonochemical assisted synthesis of a novel TiO2/graphene composite for solar energy conversion

In this paper, sonication as a common laboratory tool was used to drive chemical reaction between graphene oxide (GO) and titanium alkoxide. Firstly, we activated the GO using poly (acrylic acid) (PAA) in order to increase carboxylic groups on graphene surface. Secondly, a hydrolysis product of Ti(OH)X from tetrabutyl titanate (TNB) were assembled on activated GO surface using sonochemical reaction (100 W, 50 Hz). After annealed at 400 °C in Ar, a high quality TiO2/graphene composite with great visible response were obtained, which was attributed to sonication improving GO sheets dispersion degree and accelerating chemical reaction resulted in partial formation of a TiC and TiOC bonds. The results of both the Rh.B degradation and photocurrent tests indicated that the photocatalytic and photoelectrochemical (PEC) activities of the TiO2/graphene composite are much higher than those of commercial P25.