Oxygen Vacancies Enriched Fe2(MoO4)3 for Efficient Photo-Fenton Degradation of Tetracycline Hydrochloride

The composition, morphology and optical properties of the catalyst were characterized using XRD, SEM, EDS mapping, XPS, UV-Vis DRS, EPR and BET analyses. The results indicate that grinding and mixing iron molybdate with tartaric acid, followed by a second calcination, significantly enhances the specific surface area of the iron molybdate, creates a wealth of oxygen vacancy defects, and improves its light absorption capacity and photocatalytic activity.

Under conditions of pH = 4, 5 mg of catalyst, and 30 μL of 30% H2O2, the oxygen-vacancy-containing iron molybdate catalyst achieved a degradation efficiency of 82.2% for hydrochloride tetracycline within 30 min, representing a 36.6% improvement over the pure iron molybdate system, and maintained a high degradation efficiency even after five cycles. Radical trapping experiments and EPR spectroscopy indicated that •OH, •O2− and h+ all participate in the degradation process.