Work

Enhancing electron transfer by amorphous FeOOH quantum dots during photocatalytic ozonation of ibuprofen

Year: 2024

Type: article

Abstract: Photocatalytic ozonation (PCO) process, as an effective water purification technology, was restrained by the low mass transfer and easy combination of photo-carriers ( e cb - - h vb + ) of conventional semiconductor catalysts. To these end, this study synthesized FeOOH quantum-dots (FeOOH QDs) and boosted the PCO activity by its amorphous structure with Ibuprofen (IBP) as model pollutant. 81.5 % IBP was removed by FeOOH QDs PCO, but it was 59.1 % and 61.2 % for α-FeOOH and β-FeOOH PCO, respectively. FeOOH QDs PCO performed well at alkaline environment but was easily inhibited by co-existing ions like SO 4 2- , HCO 3 – , NO 3 – , and Cl - . Compared with those of α-FeOOH and β-FeOOH, FeOOH QDs had the narrowest band gap and the lowest e cb - - h vb + recombination, therefore, its e cb - was more favorable to activate O 3 into •OH. Tetrahedral Fe 3+ and octahedral Fe 3+ co-existed on FeOOH QDs and the tetrahedral Fe 3+ was more conducive to the adsorption of O 3 and contributed to its better PCO activity. •OH was the major reactive oxygen species accounting for IBP degradation. During FeOOH QDs PCO process, 3 degradation routes were proposed basing on 13 kinds by-products. T.E.S.T. result indicated that most of the intermediates were less toxic than IBP. This study is useful for developing catalysts for PCO process.

Source: Separation and Purification Technology

DOI: 10.1016/j.seppur.2024.131213