Songlin Ran

Novel Ag3PO4/CeO2 p-n Hierarchical Heterojunction with Enhanced Photocatalytic Performance

The composite Ag3PO4/CeO2 photocatlyst, a novel p-n type heterojunction, has been successfully fabricated through a facile hydrothermal process combined with a successive in situ precipitation technique. The X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and UV-visible diffuse reflectance spectra (DRS) were used to characterize the as-obtained products. The SEM and TEM image show that CeO2 particles have been successfully loaded and well distributed in the surface of Ag3PO4. The photocatalytic activities of the p-Ag3PO4/n-CeO2 heterojunctions were investigated for their efficiency on the degradation of Rhodamine B (RhB) under ultra-violet light and visible light irradiation, and the results showed that the p-Ag3PO4/n-CeO2 heterojunctions possessed remarkable photocatalytic activities. The enhanced photocatalytic activity can be attributed to the extended absorption in the visible light region resulting from the Ag3PO4 and the effective separation of photogenerated carriers driven by the internal electrostatic field in the junction region.

Activation of peroxymonosulfate by BiFeO3 microspheres under visible light irradiation for decomposition of organic pollutants

Visible light responsive BiFeO3 microspheres were successfully synthesized by hydrothermal method and firstly used to activate peroxymonosulfate (PMS) for oxidation and degradation of organic pollutes in water. Rhodamine B (RhB) was used as a model of organic pollutants. It was found that BiFeO3 reveals a high ability to activate PMS so that the activated PMS can generate reactive oxidative radicals for further degradation of RhB. In addition, BiFeO3 exhibited high stability and reusability in degrading organic pollutants through activation of PMS. Here, comprehensive studies on the kinetics of the reaction, PMS concentration and reaction temperature have been done and the possible mechanism was then proposed.

One-step synthesis of Ag3PO4/Ag photocatalyst with visible-light photocatalytic activity

A highly efficient photocatalyst Ag3PO4/Ag was prepared by a one-step low temperature chemical bath method. The reflectance spectra (DRS) indicated Ag3PO4/Ag had strong absorption in visible light region. The synthesized Ag3PO4/Ag photocatalyst was used as the efficient photocatalysts for the photocatalytic degradation of Rhodamine B (RhB) under visible-light illumination which showed almost complete degradation (~ 98%) of RhB dye in 90 min. The negative surface of Ag3PO4/Ag photocatalyst also promoted the degradation of a cationic dye like methylene bule (MB; 78% in 90min), while the performance against an anionic dye like methyl orange was poorer (MO; 40% in 90 min). Compared to the pure Ag3PO4 photocatalyst, the Ag3PO4/Ag photocatalyst showed the enhanced visible light photocatalytic informance. The excellent photocatalytic performance is mainly ascribed to the surface plasmon resonance of Ag nanoparticles and a large negative charge of PO43- ions.

Novel α-FeOOH Nanorods/Ag3PO4 Semiconductor Composites with Enhanced Photocatalytic Activity and Stability

The composite α-FeOOH nanorods/Ag3PO4 photocatalyst has been successfully fabricated through a facile hydrothermal process combined with a successive in situ precipitation technique. The SEM and TEM images show that Ag3PO4 particles have been successfully loaded on the surface of FeOOH nanorods. The photocatalytic activities of the α-FeOOH/Ag3PO4 composite were investigated for their efficiency on the degradation of Rhodamine B (RhB) under ultra-violet light and visible light irradiation, and the results showed that the α-FeOOH/Ag3PO4 composite possessed remarkable photocatalytic activities. The enhanced photocatalytic activity can be attributed to the strong absorption in visible light and the effective separation of photogenerated hole–electron pairs between Ag3PO4 and α-FeOOH.

Effects of TiO2 on the Microstructure of Synthesized Elongated Mullite

Elongated mullite was synthesized via an in situ solid-phase reaction using α-Al2O3 and SiO2 as the raw materials and TiO2 as an additive, and characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). On the basis of thermodynamic analysis of the reaction process, the effects of TiO2 content and reaction temperature on the phase composition, phase contents, and microstructure of the synthesized samples were investigated. The results showed that elongated mullite with a length of about 8.0 μm was formed for the sample with 7 mass-% TiO2 at 1873 K. The dosage of TiO2 exceeded its solid solubility limit in mullite which resulted in the anisotropic growth of mullite grains.