Search

A novel N H TiO 2 photocatalyst was prepared via hydrothermal synthesis followed by a thermal treatment in NH 3 and H 2 atmospheres. The results showed that benzene with the initial concentration of 150 ppm (±5 ppm) could be thoroughly removed by N H TiO 2 under visible light irradiation. The influences of doping and hydrogenation on properties of TiO 2 samples were investigated. It is suggested that the disordered surface layer introduced by hydrogenation contributes to the excellent photocatalytic activity of N H TiO 2 . The synergistic effect of N doping and surface oxygen vacancies was also confirmed by ultraviolet–visible diffuse reflectance spectra and photoluminescence. Moreover, the diverse role of oxygen vacancies in different positions of TiO 2 has been focused on. [ABSTRACT FROM AUTHOR]

Abstract: Novel heterojunction MgFe2O4–ZnO was employed as a photocatalyst to photodegrade organic pollutants Rhodamine B (RhB). This heterojunction was prepared by two steps. First, ZnO flower-like nanotube bundles were synthesized by using a simple solution method at low temperature. Second, MgFe2O4 was coated on ZnO surfaces on the basis of a chemical co-precipitation method. The as-prepared samples were characterized with X-ray diffraction (XRD), UV-3150 double-beam spectrophotometer, field-emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM), and high-resolution transmission (HRTEM). Photodegradation experiments results indicated that the obtained heterojunction MgFe2O4–ZnO exhibited higher photocatalytic activity than that of pure ZnO or MgFe2O4. Furthermore, MgFe2O4–ZnO could be separated conveniently by using an external magnetic field. The enhanced photocatalytic ability of MgFe2O4–ZnO composites could be attributed to the interconnected heterojunction of MgFe2O4 and ZnO nanoparticles. [Copyright &y& Elsevier]