Facile synthesis, structural, optical and photocatalytic properties of anatase/ rutile mixed phase TiO2 ball-like sub-micron structures

Abstract

We report facile synthesis of ball-like sub-micron structures of TiO2 with strong photocatalytic activity. FESEM and TEM studies showed ball-like sub-micron TiO2 structures. XRD results showed that the synthesized TiO2 sub-micron structures annealed at 300 °C exist in pure anatase phase, while annealing at 600 °C led to the creation of mixed phase TiO2 structures. The photocatalytic studies showed that anatase/ rutile mixed phase TiO2 ball-like sub-micron structures exhibit superior photocatalytic activities for the decomposition of Rhodamine B (RhB) and methyl orange (MO) dyes. We attribute the observed improved photodegradation activities of anatase/ rutile mixed phase TiO2 sub-micron structures to the synergistic effects of large surface area of ball-like TiO2 structures facilitating enhanced adsorption of dye molecules and the mixed phase composition resulting in improved charge separation efficiency.