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Developing nonmetal-doped mesoporous TiO₂ is highly attractive for preparing semiconductor visible photocatalyst with high activities. Here, we prepare N/F co-doped mesoporous TiO₂ with high vis-photocatalytic activities by a simple liquid phase deposition process followed by annealing in air using C${}_{16}$TAB as a bi-functional template (forming mesoporous and providing dopants). N₂ adsorption isotherms, low-angle X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicate the formation of wormhole-like mesoporous structure. Wide-angle XRD and high-resolution TEM demonstrate the presence of anatase TiO₂ mesopore wall. XPS analyses reveal that N is doped into TiO₂ lattice in the forms of substitutional and interstitial N species, and that F is doped into the TiO₂ lattice in the form of interstitial F. The mesopore-forming and doping mechanisms are thoroughly discussed based on the bi-function of C${}_{16}$TAB template. Mesoporous structure results in a high BET surface area of TiO₂. High-concentration nitrogen species in anatase lattice and mesoporous structure remarkably increase the visible absorption of TiO₂. As a result, the reaction rate constant of MB degradation catalyzed by N/F co-doped mesoporous TiO₂ photocatalysts is about 7 times that by P25.

ZnO/Bi₄V₂O${}_{11}$ nanocomposites were prepared via a facile hydrothermal method by loading different amounts of ZnO onto the surface of Bi₄V₂O${}_{11}$. The resulting ZnO/Bi₄V₂O${}_{11}$ composites showed excellent photocatalytic activity than that of pure ZnO under visible light irradiation. When the ratio of ZnO to Bi₄V₂O${}_{11}$ was 1:1 (ZB2), the photocatalytic activity was best, which could degrade RhB almost completely within 30min. The enhanced photocatalytic activity of ZnO/Bi₄V₂O${}_{11}$ composites could be mainly ascribed to the efficient charge separation and the increased specific surface area. Based on the experimental and bandgap calculations, a possible photocatalytic mechanism was proposed.

A novel spherical N-CQDs/BiOI photocatalyst was successfully synthesized through a facile solvothermal method. The optimization experiments of hydrothermal time and temperature were carried out. The effect of ammonium citrate addition was investigated. The as-synthesized photocatalysts were characterized via X-ray diffraction, scanning and transmission electron microscopy, Fourier transform infrared spectrum and elemental analysis. The adsorption and photocatalytic performance of as-synthesized photocatalysts were studied, 0.2N-CQDs/BiOI showed the best performance. For the removal of anionic dye RhB, adsorption occupied a major position. The maximum adsorption capacity was 97.09mg/g for RhB. For the removal of cationic dyes X3B, photocatalysis occupied a major position. The photocatalytic activity of 0.2N-CQDs/BiOI was superior to that of nano-TiO₂ under the simulate sunlight irradiation. Different scavengers were used to analyze the effect of active species and photocatalytic degradation mechanism of X3B. The outstanding stability and performance make 0.2N-CQDs/BiOI has highly potential applications in wastewater treatment.