Influence of the preparation method on the photocatalytic activity of Nd-modified TiO₂

Abstract

Nd-modified TiO2 photocatalysts have been obtained via hydrothermal (HT) and sol–hydrothermal (SHT) methods. The as-prepared samples were characterized by X-ray diffraction (XRD), BET surface area measurements, scanning electron microscopy (SEM), diffuse reflectance spectroscopy (DRS), luminescence spectroscopy and X-ray photoelectron spectroscopy (XPS). The photocatalytic activity of the synthesized samples was evaluated by the degradation of phenol in aqueous solution under irradiation with UV–vis (λ > 350 nm) and vis (λ > 420 nm) light, as well as by the degradation of gaseous toluene under irradiation with vis (λmax = 415 nm) light. It was found that Nd-modified TiO2 is an efficient photocatalyst for the degradation of phenol and toluene under visible light. XPS analysis revealed that the photocatalyst prepared via HT method contains a three-times higher amount of hydroxy groups at the surface layer and a two-times higher amount of surface defects than that obtained by the SHT method. The photocatalytic efficiency of phenol and toluene degradation under vis irradiation in the presence of 0.25% Nd-TiO2(HT) reached 0.62 and 3.36 μmol·dm−1·min−1, respectively. Photocatalytic activity tests in the presence of Nd-TiO2 and scavenger confirm that superoxide radicals were responsible for the visible light-induced degradation of the model pollutant in aqueous solution.

Defect engineered (Er3+/Nd3+) codoped TiO2 photoanodes for enhanced photoelectrochemical and photovoltaic applications

“…In addition, it shows sharp absorption peaks at 520 nm, 585 nm, and 745 nm, enhancing absorption abilities. 65 Notably, the absorption spectra of (Er : Nd) codoped TiO 2 exhibited both the Er and Nd-related absorption bands. The appropriate doping ratio of Er to Nd is expected to increase the absorption properties due to energy transfer (ET) between the Er and Nd energy levels.…”

Fabrication and Characterization of Lanthanide-TiO<sub>2</sub> Nanotube Composites

“…The crystal phases of P25 TiO 2 and un-doped and doped TNTs are shown in The occasional absence of sharp peaks corresponding to Nd and/or Gd in the XRD patterns could be attributed to small or highly dispersed concentrations below the detection limit, or they were located inside the TiO 2 lattice (i.e., TNT doping) [39].…”

3D structured TiO2-based aerogel photocatalyst for the high-efficiency degradation of toluene gas

“…[11][12][13] An efficient photocatalyst is the key to the degradation of VOCs. 14,15 However, so far, the use of photocatalytic technology to degrade VOCs faces two problems: (1) the low photocatalytic efficiency 16,17 and (2) the poor binding force between the powdered catalyst and the carrier. 18,19 Researchers are committed to constructing novel heterojunction structures, e.g., TaON/Bi 2 MoO 6 , AgI/BiSbO 4 , and BiPO 4 /g-C 3 N 4 , to promote the separation of photogenerated carriers.…”