New Insights Into BiVO₄ Properties as Visible Light Photocatalyst

Abstract

Bismuth vanadate has attractive photocatalytic properties under visible light. The influence of structure and morphology of BiVO 4 nanomaterials on its photocatalytic properties in the UV and the visible domain was investigated. The selection of different sets of synthetic parameters in aqueous solutionpH or the use of organic additivesallowed the formation of tetragonal zircon, tetragonal scheelite, and monoclinic scheelite structure and different morphologies of that last phase. First, the tetragonal zircon was found to be the only inactive structure. Then, the best material for photocatalytic degradation of rhodamine B in solution and stearic acid deposited directly on the photocatalyst is the core−shell tetragonal zircon−monoclinic scheelite system prepared in the presence of sodium dodecyl sulfate. The enhanced properties are explained by the presence of strong surface acidic sites corresponding to the presence of surface sulfate residues rather than to the specific morphology of the material. Additionally, an EPR study on the ability of BiVO 4 to generate active surface radical showed that hydroxyl radicals are not generated and that superoxide ion concentration under irradiation is close to the detection threshold. Depending on the selected irradiation wavelength, bismuth vanadate may present a better photocatalytic activity than titanium oxide. It is shown to be equivalent to bismuth tungstate under blue light.

New Insights into Mn1−xZnxFe2O4 via Fabricating Magnetic Photocatalyst Material BiVO4/Mn1−xZnxFe2O4

“…The hybridization of Bi 6s -O 2p orbitals upshifted the valence band of monoclinic BiVO 4 to a lower potential at about +2.4 eV [2,4,5,6,7]. Nonetheless, the photocatalytic efficiency of BiVO 4 is generally low because of its poor electron transfer and slow reaction kinetics.…”

Voltage-dependent reconstruction of layered Bi2WO6 and Bi2MoO6 photocatalysts and its influence on charge sep

“…1; the intercalation of bismuth oxide layer in WO 3 creates electronic states above the valence band maximum, thereby reducing the band gap of WO 3 . In addition to WO 3 , this method has been successfully used to enhance light absorption in a range of semiconducting ABO 3 and BO 3 metal oxides for use as photocatalytic electrode materials [10][11][12][13][14][15][16][17] .…”

A Novel Technique for the Deposition of Bismuth Tungstate onto Titania Nanoparticulates for Enhancing the Visible Light Photocatalytic Activity

“…Thus, titanium dioxide coupled with such materials, as CdS [5], WO 3 [6], Cu 2 O [7], etc has been reported. Bismuth tungstate (Bi 2 WO 6 ) is gaining increasing popularity as a narrow band gap semiconductor that exhibits good photocatalytic properties under visible light irradiation [8,9]. Several successful attempts to couple bismuth tungstate with titanium dioxide have been reported recently [10][11][12].…”