Photocatalytic properties, mechanical strength and durability of TiO/cement composites prepared by a spraying method for removal of organic pollutants.

TiO/cement composites were prepared by a spraying method to degrade organic pollutants. After coated with waterproof liquid, pure cement pastes/mortars were sprayed with TiO suspensions with different TiO contents and spraying times. Photocatalytic properties, mechanical strength and durability were studied. Maximum photocatalytic activity and uniform TiO distribution were achieved at the optimal conditions of 10 wt% TiO content in suspension and 3 spraying times. The TiO/cement pastes had better degradation performance over Rhodamine B (RhB) and methylene blue (MB) than that over methyl orange (MO). After 20 times of cycling degradation, the photocatalytic efficiencies had no significant reduction. The TiO/cement mortars had good mechanical strengths, meeting the mechanical demands of wastewater treatment tanks. In durability, the TiO/cement mortars had better water penetration resistance, chloride penetration resistance and anti-carbonation than pure cement mortars.