Study on molecularly imprinted TiO2 photocatalytic selective degradation of ethyl hydroxybenzene wastewater and the effect of different pollutant models on the quenching mechanism

摘要

A molecularly imprinted titanium dioxide (EP-TiO2) 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 TiO2 and EP-TiO2. EP was found to inhibit the agglomeration of particles, resulting in a reduction of the forbidden band width of EP-TiO2 by 0.22 eV compared to TiO2. The selectivity coefficient of EP-TiO2 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-TiO2 for EP by 59.22% compared to TiO2. 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-TiO2. Within 30 min, the decolorization of EP by EP-TiO2 reached 78.60%, demonstrating the superior photocatalytic performance of the synthesized EP-TiO2 and its potential application in the efficient degradation of EP wastewater.

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