Fabrication of a novel MoO3/Zn-Al LDHs composite photocatalyst for efficient degradation of tetracycline under visible light irradiation

Herein, a novel MoO3/Zn-Al LDHs composite photocatalyst was successfully prepared. Morphology, chemical composition, and photoelectrochemical properties of the prepared catalyst were explored by different characterization methods, including X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), Brunauer Emmett-Teller (BET), UV-Vis diffuse reflectance spectrometry (DRS) and Electron Spin Resonance (ESR). Using tetracycline as a target pollutant, the photocatalytic activity of MoO3 (10 wt%)/Zn-Al LDHs composite was tested by photodegradation of tetracycline under visible light irradiation. The experimental results indicate that the MoO3 (10 wt%)/Zn-Al LDHs composite exhibited higher photocatalytic removal efficiency than pure Zn-Al LDHs and MoO3. The removal efficiency of TC in 60 min could reach 90.5%. It was confirmed that the optimal conditions were a catalyst dosage of 1.0 g/L, an initial pH of 9, and an initial concentration of TC of 40 mg/L. In addition, a possible mechanism for the photodegradation of TC with MoO3 (10 wt%)/Zn-Al LDHs composite was proposed. The introduction of MoO3 facilitates the separation of electron-hole pairs. It could be seen that the MoO3 (10 wt%)/Zn-Al LDHs composite has great application prospects for the treatment of antibiotic wastewater.

Automated summary

A novel MoO3/Zn-Al LDHs composite photocatalyst was successfully prepared and characterized. The composite showed higher photocatalytic removal efficiency for tetracycline compared to pure Zn-Al LDHs and MoO3. The introduction of MoO3 facilitates the separation of electron-hole pairs, indicating great potential for antibiotic wastewater treatment.