Improved visible light photocatalytic activity of titania loaded with silver on discoloration of a heterocyclic aromatic chemical dye solution

Abstract

The photocatalytic activity of silver deposited Degussa P25 titanium dioxide (Ag DP25) in the photodegradation of methylene blue (MB) was investigated. The as prepared materials were characterized by X ray diffraction (XRD), transmission electron microscopy (TEM), UV vis diffuse reflectance spectroscopy (DRS), infrared spectra and surface photovoltage spectroscopy (SPS) techniques. The obtained results show that the silver dopant could effectively inhibit the recombination of the photoinduced electron and holes, improving the absorption capability for visible light of photocatalyst and leading to increased surface OH group density. The degradation experiment reveals that the catalytic property of Ag DP25 in the degradation of MB dye is more efficient than that of commercially available Degussa P25 TiO 2 (DP25) samples under vis ible light irradiation. Besides, degradation kinetics of MB dye can, be well described by Langmuir-Hinshel wood equation and shows pseudo first order law.

Photocatalytic Properties of Titanium Dioxide Thin Films Doped with Noble Metals (Ag, Au, Pd, and Pt)

“…In order to explain the photocatalytic behavior shown in this work, two aspects should be considered: first, narrowing of the band gap due to the SMSI effect and second, trapping of photo‐excited electrons by the metal particles, reducing the recombination of e − /h + pairs and contributing to a stronger photocatalytic activity . The work function of Pt, Pd, Au, Ag, and TiO 2 is 5.64, 5.12, 5.1, 4.6, and 4.2 eV, respectively .…”

Preparation of carbon nanotubes/BiOBr composites with higher visible light photocatalytic activity

“…Therefore, the development of a visible light driven photocatalysts consequently has become one of the most pivotal topics in current pho tocatalysis research. To date, there are two main syn thetic strategies to develop such photocatalysts: chem ical modification of an UV-active photocatalyst (for example, TiO 2 ) [4][5][6][7][8], and exploration of novel semi conductor materials [9][10][11][12][13][14]. As a new prospective vis ible light driven photocatalyst, bismuth oxyhalide compounds BiOX (X = Cl, Br, and I) have recently attracted increasing interest because of their good photocatalytic activity under UV or visible light illu mination [15,16], unique layered structure, good cat alytic activity, and high photocorrosion stability.…”