Photocatalytic performance of doped TiO2/AC coating and its UV stability research

[Display omitted] •A nitric oxide removal coating was constructed by loading doped TiO2/AC photocatalyst on waterborne acrylic coating.•Under visible light irradiation, the NO degradation efficiency of doped TiO2/AC coating was 45.8 % in 2 h, and only decreased by 5.8 % after 5 cycles.•UV stability of doped TiO2/AC coating was investigated, and the mechanism of improving UV stability was proposed.•After 42 d UV aging and single water flushing, the NO removal efficiency of doped TiO2/AC coating still reached 36.7 % and exhibited excellent UV stability. Based on the porous structure of activated carbon (AC) and the photo-oxidation behavior of TiO2, a visible-light-responsive photocatalytic coating with UV stability was constructed by loading Fe/N/Co-TiO2@AC (DTC) on waterborne acrylic coating. The DTC with adsorption and degradation synergistic effect was prepared by a simple mechanochemistry method and characterized by UV–vis, SEM, XRD, and BET. The nitric oxide (NO) removal efficiency of DTC was 51.6 % under visible light in 2 h. Besides, under the same conditions, the NO removal efficiency of the DTC coating still reached 45.8 %. Further, to investigate the UV stability of DTC coating, different coatings were prepared with the same dosage of DTC, TiO2@AC (TC), and TiO2. The UV stability of the coatings was tested with a color difference, degree of chalking, adhesion strength, hardness, and impact resistance as evaluation indicators. The results showed that the DTC coating exhibited the best UV stability. The photooxidation of organic binder on the coating surface before and after aging was micro-characterized by SEM and FT-IR, and the UV stability improvement mechanism was revealed.