The effects of ZSM-5 zeolite on ofloxacin degradation on Sm2Ti2O7 photocatalyst

The NaZSM-5 (NaZ) and HZSM-5 (HZ) zeolites were used to synthesize the Sm2Ti2O7 (STO)-ZSM-5 composites via a sol-gel route. An interesting finding is the enhanced photocatalytic activity of the STO-zeolite composites. The STO-HZ and STO-NaZ composites are composed of 70% STO and 30% zeolite, and the zeolite particles are surrounded by a STO layer. The chemical environments of Sm, O and Ti in the STO are not influenced by the zeolite. The photoluminescence intensities of the materials are in the sequence of STO, STO-NaZ and STO-HZ. The STO-HZ composite has the strongest photocatalytic activity, and the optimum STO dosage for ofloxacin degradation is 600 mg/L. The degradation of ofloxacin during photocatalytic reaction was determined using the UV-Vis spectrum and FT-IR spectrum of the ofloxacin solution. The typical organic groups in the ofloxacin are decomposed in the oxidation reaction. The mineralization of ofloxacin and the degradation of the oxidation intermediates result in the formation of F-, NO2- and NH4+ ions.

Automated summary

The NaZSM-5 and HZSM-5 zeolites were used to synthesize the Sm2Ti2O7-ZSM-5 composites, which exhibited enhanced photocatalytic activity. Among the composites, STO-HZ showed the strongest photocatalytic activity. The photoluminescence intensity measurement confirmed the catalytic performance of the composites.