Unusual catalytic activity of TiO2–CoTiO3 under 1064 nm pulsed laser illumination

Abstract We present the properties of a photo-catalytically activated CoTiO3 framework supported on TiO2 (rutile). To demonstrate the effectiveness of this TiO2–CoTiO3 compound under light illumination, we tested its degradation potential against acid orange 7 dye. The dye degradation is effective over a wide range of laser excitation wavelengths from 1064 nm to 532 nm as well as at sunlight simulation conditions. The TiO2–CoTiO3 compound particles have sizes from 100 nm to a few microns and provide a surprising photocatalytic enhancement under 1064 nm pulsed laser excitation, that is, at photon energies well below the light absorption edge. We attribute the high activity of this material to the interphases between the rutile and CoTiO3 and discuss a number of possible mechanisms for the photocatalytic enhancement under pulsed laser excitations. The dye degradation activity of TiO2–CoTiO3 increases up to two orders of magnitude when compared to pure TiO2 or 20at%Co-TiO2 with TiO2 in either phases, amorphous or anatase.