Guifu Zuo

Effect of pH and molar concentration on photocatalytic performance of BiVO4 synthesised by sol–gel method

In this study, a series of monoclinic BiVO4 photocatalysts were successfully synthesised by the sol–gel method by varying pH and molar concentration. The structural and morphological properties of the synthesised BiVO4 photocatalysts were characterised by X-ray diffraction and scanning electron microscopy, respectively. The photocatalytic activity of the catalysts was evaluated by the degradation of RhB under visible-light irradiation. The results indicate that at pH = 7, the catalysts showed the best photocatalytic activity, reaching up to 90.9%. Furthermore, at 0.2M concentration, the catalysts showed the best photocatalytic activity, reaching up to 89.4%. The catalysts synthesised at different pH and molar concentrations exhibited different photocatalytic activities under visible-light irradiation because different conditions led to different degrees of crystallinity and grain distributions of monoclinic BiVO4.

Self assembly and controlled drug release of a nano-laminated graphite carbon nitride/methotrexate complex

AbstractIn this study, g-C3N4/methotrexate (g-C3N4/MTX) nanohybrids were obtained via a self assembly method. XRD and TEM demonstrated that bulk g-C3N4 had been stripped into thin nanosheets with size range of 150–250 nm. FTIR investigation indicated that the self assembly of the hybrid was attributed to the hydrogen bond between g-C3N4 nanosheets and MTX molecules. It is confirmed by the UV-vis spectra that the hybrids can achieve a sustained drug release within long period for 70 h. Furthermore, the drug release mechanism was investigated by kinetic models and a first-order relationship was concluded, which indicated that the drug release is a simple diffusion process cohydroxyapatite/methotrexate complexntrolled by gradient drug concentration. Cell viability tests confirmed that g-C3N4 presented excellent biocompatibility and g-C3N4/MTX hybrids had obvious suppression efficiency on MG63 cells which showed a positive correlation to the drug concentration and incubation time.

Influence of Heat Treatment on Photocatalytic Performance of BiVO4 Synthesized by Hydrothermal Method

Abstract Monoclinic BiVO4 photocatalyst was successfully synthesized by hydrothermal method under appropriate temperature. The photocatalytic performance of BiVO4 was improved by calcining at appropriate temperature. The structural and morphological properties of the synthesized BiVO4 photocatalysts were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. It is confirmed that the photocatalytic activity of the prepared catalysts was evaluated by the photodegradation of RhB under visible-light irradiation. BiVO4 calcined under appropriate temperature exhibited higher photocatalytic activity than uncalcined BiVO4 under visible light irradiation because calcination might effectively increases the purity of monoclinic bismuth vanadate.