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S-schematic CuWO 4 /ZnO nanocomposite photocatalyst was synthesized by an impregnation method. Synthesized CuWO 4 and ZnO nanoparticles, and CuWO 4 /ZnO nanocomposites were thoroughly characterized. X-ray diffraction (XRD) analysis of the CuWO 4 /ZnO nanocomposite confirmed the respective triclinic and hexagonal wurtzite structures of CuWO 4 and ZnO crystals. Raman and Fourier transform infrared (FTIR) spectra and X-ray photoelectron spectroscopy (XPS) revealed bond formations in CuWO 4 and ZnO, and confirmed the synthesis of the CuWO 4 /ZnO nanocomposite. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed CuWO 4 nanoparticles adhered to ZnO aggregates. Energy dispersive X-ray spectrometry (EDS) confirmed the distribution of CuWO 4 on the ZnO aggregates. UV–Vis diffuse reflectance spectroscopy (DRS) showed optical bandgap energies of 2.36 eV for CuWO 4 and 3.18 eV for ZnO nanoparticles. The photocatalytic performance of the CuWO 4 /ZnO nanocomposite was investigated through the degradation of the cationic dyes methylene blue (MB) and Rhodamine B (RhB) and the anionic dye methyl orange (MO). A 5.0%CuWO 4 /ZnO nanocomposite degraded 100% of MB within 120 min, 91.02% of RhB within 300 min, and 89.13% of MO within 300 min. The pseudo-first order kinetic rate constant fit well for the degradation of all the dyes on the CuWO 4 /ZnO nanocomposite. The CuWO 4 /ZnO nanocomposite could better degrade the cationic dyes than the anionic dye in an aqueous solution. The hole (h+), the hydroxyl radical (•OH), and the superoxide ion (• O 2 −) were the active species responsible for degrading MB, RhB and MO dyes. The proposed CuWO 4 /ZnO nanocomposite could be applied for environment friendly wastewater treatment. [Display omitted] • CuWO 4 /ZnO nanocomposites were synthesized by an impregnation method. • 5.0%CuWO 4 /ZnO nanocomposite showed the best photocatalytic degradation. • Photogenerated electron-hole pair recombination decreased due to S-schematic charge transfer. • 5.0%CuWO 4 /ZnO nanocomposite degraded 100% of MB, 91.02% of RhB and 89.13% of MO. • h+,.•OH and • O 2 − were active species responsible for photocatalytic degradation. [ABSTRACT FROM AUTHOR]

A novel all-solid-state Z-scheme visible-light-driven photocatalytic material, CuBi 2 O 4 /In 2 O 3 was successfully prepared by loading CuBi 2 O 4 onto flower-like In 2 O 3. The resulting material was characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, UV-diffuse reflectance spectroscopy (UV-DRS), Brunauer–Emmett–Teller (BET) surface area, X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), Raman spectroscopy, and X-ray diffraction (XRD). Compared with single-phase CuBi 2 O 4 and In 2 O 3 , the coupled composite phase of 15% CuBi 2 O 4 /In 2 O 3 (15CuIn) showed superior photocatalytic activity. Its decolorization rate of methylene blue (MB) could reach 97% in 80 min under visible light irradiation and could be maintained at 85% after four cycles. The outstanding photocatalytic performance of CuBi 2 O 4 /In 2 O 3 was attributed to the formation of a Z-scheme heterogeneous structure, which increased the visible light absorption, enhanced the specific surface area, and improved the interfacial charge transfer efficiency. This study provides a novel approach for the construction of efficient heterojunction photocatalysts for wastewater treatment. • A novel all-solid-state visible-light photocatalyst CuBi 2 O 4 /In 2 O 3 was first successfully prepared. • The decolorization rates of MB could reach 97% in 80 min. • The Z-scheme heterogeneous structure increases visible light absorption, and improves interfacial charge transfer efficiency. [ABSTRACT FROM AUTHOR]

As an advanced oxidation process, the catalytic efficiency of photocatalysis has been greatly improved because the size of catalytic materials has been reduced to nano level. However, the reduced size also makes it more difficult to reuse. In view of the fact that hydrogel composite photocatalyst can improve the practicability and economy of photocatalyst, the research and application of hydrogel composite photocatalyst deserve to be concerned. In this review, the research on hydrogel as the carrier of photocatalyst (Mainly including Titanium oxide, Carbon nitride, Metal sulfide) and the selection and preparation methods of hydrogel in recent five years is summarized. The factors affecting the photocatalytic efficiency of the composite gel system and the evaluation indexes are listed and discussed in detail. In addition, the mechanism of synergistic degradation of hydrogel composite photocatalyst was also discussed. The results showed that photocatalytic degradation and hydrogel adsorption promoted each other. Finally, the existing problems of hydrogel composite photocatalyst are summarized, and the development prospect is forecasted. [ABSTRACT FROM AUTHOR]

Abstract: Lanthanum ferrite nanoparticles (LaFeO3 NPs) with light absorption properties in the visible region were successfully synthesized in CTAB (cetyltrimethyl ammonium bromide) emulsion nanoreactors at room temperature. The morphology, size, structure, elemental composition, and optical properties of these particles were characterized by field emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), X-ray fluorescence (XRF), and ultraviolet–visible absorption (UV–Vis) spectroscopy. Through this method, highly crystalline and well-dispersed perovskite LaFeO3 NPs with a phase-pure were successfully obtained. The band gap energy (E g) of the LaFeO3 NPs was calculated by UV-Vis spectroscopy at the wavelength of about 517nm and is observed to have a value of 2.43eV. The photocatalytic activities of LaFeO3 NPs were evaluated by the degradation of toluidine blue O (TBO, used as a probe) dye under visible light irradiation, which exhibits a high photocatalytic TBO dye degradation activity as compared to the commercial P-25 titania powder. This phenomenon is due to smaller band gap energy and changing from bulk to nanostructure. The higher photocatalytic activity is also related to the photo absorption. [Copyright &y& Elsevier]