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[Display omitted] • A new MgFe 2 O 4 /Bi 2 WO 6 composite photocatalyst was successfully prepared by wet ball milling process. • Through DFT calculations and a series of characterizations, it was confirmed that the MgFe 2 O 4 /Bi 2 WO 6 composite material conforms to the Z-scheme electron transfer mechanism. • The degradation rate of TCH by 25%-MgFe 2 O 4 /Bi 2 WO 6 composite photocatalytic material is as high as 95.82%. • · OH and · O 2 – are the main active substances in this photocatalytic reaction. • The composite has high stability in repeated experiments. In this study, a new Z-scheme MgFe 2 O 4 /Bi 2 WO 6 heterojunction was successfully prepared by hydrothermal and wet ball milling process. The results of the study showed that after 90 min of visible light exposure, the photocatalytic degradation of tetracycline hydrochloride (TCH) by 25%-MgFe 2 O 4 /Bi 2 WO 6 heterojunction was as high as 95.82%, and the highest photocatalytic rate (0.0281 min−1) was 4.61 and 3.43 times higher than that of pure Bi 2 WO 6 (0.0061 min−1) and MgFe 2 O 4 (0.0082 min−1), respectively. Furthermore, spin-polarized density functional theory (DFT) calculations were performed to provide additional evidence of the presence of a Z-scheme charge transfer mechanism between MgFe 2 O 4 and Bi 2 WO 6. We investigated the effects of initial TCH concentration, pH, coexisting ions and different water sources on the efficiency of photocatalytic degradation of TCH in composite samples. The recovery experiments demonstrated that the MgFe 2 O 4 /Bi 2 WO 6 composites had good stability and repeatability. A series of experimental results showed that 25%-MgFe 2 O 4 /Bi 2 WO 6 had a larger specific surface area, better ultraviolet and visible absorbance, superior charge transfer and higher efficiency of photogenerated electron-hole pair separation. This paper provides new ideas for the design and preparation of new Z-scheme heterojunctions and has great prospects for practical applications in the field of wastewater treatment. [ABSTRACT FROM AUTHOR]

The energy level diagram for electronic transfer vs. Vacuum level; (B and C) The photocatalytic mechanism over EY-sensitized UiO-66/WP. The abundant transition metal phosphides co-catalysts on the earth can satisfy the sustainable and clean solar H 2 production through photocatalytic water splitting, which is promising to replace the rare precious metals, such as Pt, Au, Pd, Ru and so on. In this paper, we use the temperature-programmed solid phase method to prepare WP nanoparticles. Based on the Density Functional Theory (DFT) calculations, we demonstrate that the WP nanoparticles possess outstanding electrical conductivity and excellent capability to transport electrons. WP nanoparticles are loaded onto the surface of UiO-66 via the ultrasound-assisted impregnation method to induce a highly efficient visible-light photocatalytic H 2 production activity of 384 µmol in 5 h, which is 10.67 times than that of pure UiO-66. The catalytic performance is attributed to the excellent metallic conductivity and the favourable Fermi level position of WP nanoparticles. Further studies of PL, TRPL and Mott-Schottky curves, we can not only know that the modification of WP nanoparticles do improve the electron transfer ability, but also that the matched work functions between the EY and UiO-66 provides a feasible thermodynamic path for the transmission of electrons. Our work demonstrates that the earth-abundant transition metal phosphides material have the potential to construct cheaper and high catalytic performance photocatalysts. [ABSTRACT FROM AUTHOR]