Assessment of photocatalytic, superhydrophobic and self-cleaning properties on hot mix asphalts coated with TiO2 and/or ZnO aqueous solutions

Photocatalytic, superhydrophobic and self-cleaning capabilities were promoted on AC 6 and AC 14 asphalt mixtures by spraying of TiO2 and/or ZnO. Initially, physicochemical and morphological properties of bitumen samples were evaluated by Fourier Transform Infrared Spectroscopy and Atomic Force Microscopy after the solution spraying of TiO2, ZnO and TiO2 ZnO. Then, to assure those capacities, Water Angle Contact and Photocatalytic Efficiency tests were carried out on both mixtures. Finally, mixtures were assessed mechanically through Indirect Tensile Strength. Photocatalytic, superhydrophobic and self-cleaning properties were guaranteed for AC 14 with TiO2 and TiO2 ZnO and AC 6 with TiO2 ZnO without deteriorations.