Study on molecularly imprinted TiO 2 photocatalytic selective degradation of ethyl hydroxybenzene wastewater and the effect of different pollutant models on the quenching mechanism

A molecularly imprinted titanium dioxide (EP-TiO 2 ) was synthesized through a one-step molecular imprinting technique using ethyl hydroxybenzene (EP) as the imprinting molecule and tetra-n-butyl titanate as the precursor. The anatase was the main component of both TiO 2 and EP-TiO 2 . EP was found to inhibit the agglomeration of particles, resulting in a reduction of the forbidden band width of EP-TiO 2 by 0.22 eV compared to TiO 2 . The selectivity coefficient of EP-TiO 2 for the target pollutant, EP, was 1.64, indicating superior selectivity as the value exceeded 1.5. The molecular imprinting technique increased the selectivity of EP-TiO 2 for EP by 59.22% compared to TiO 2 . The quenching experiments demonstrated that photogenerated holes played a greater role than hydroxyl radicals in the degradation of EP. However, the contribution of superoxide radicals could not be accurately determined. When basic magenta replaced EP as the model pollutant, it was confirmed that superoxide radicals were the primary active species in the photocatalytic process of EP-TiO 2 . Within 30 min, the decolorization of EP by EP-TiO 2 reached 78.60%, demonstrating the superior photocatalytic performance of the synthesized EP-TiO 2 and its potential application in the efficient degradation of EP wastewater.