Role of Platinum Deposited on TiO₂in Photocatalytic Methanol Oxidation and Dehydrogenation Reactions

Abstract

Titania modified nanoparticles have been prepared by the photodeposition method employing platinum particles on the commercially available titanium dioxide (Hombikat UV 100). The properties of the prepared photocatalysts were investigated by means of the Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), atomic force microscopy (AFM), and UV-visible diffuse spectrophotometry (UV-Vis). XRD was employed to determine the crystallographic phase and particle size of both bare and platinised titanium dioxide. The results indicated that the particle size was decreased with the increasing of platinum loading. AFM analysis showed that one particle consists of about 9 to 11 crystals. UV-vis absorbance analysis showed that the absorption edge shifted to longer wavelength for 0.5% Pt loading compared with bare titanium dioxide. The photocatalytic activity of pure and Pt-loaded TiO2was investigated employing the photocatalytic oxidation and dehydrogenation of methanol. The results of the photocatalytic activity indicate that the platinized titanium dioxide samples are always more active than the corresponding bare TiO2for both methanol oxidation and dehydrogenation processes. The loading with various platinum amounts resulted in a significant improvement of the photocatalytic activity of TiO2. This beneficial effect was attributed to an increased separation of the photogenerated electron-hole charge carriers.

Removal Bismarck Brown G dye from Aqueous Solution Over a Composite of Triazole-Polyvinyl Chloride Polymer and Zinc Oxide

“…Better removal efficiency of BBG dye after one hour over composite was around 82% while it was around 68% over neat ZnO 31,32 .This significant enhancement in dye removal over composite can be attributed to the synergistic effect of triazole-PVC and ZnO. Besides that, presence of triazole-PVC particles in this composite can reduce recombination reaction between conduction band electrons ( e -CB ) and valence band holes (h + VB ) by increasing separation between these species 33 .For neat ZnO, recombination reaction occurs with high rate which leads to reduce the efficiency of the photocatalytic process.…”

Preparation, Characterization, and Photocatalytic Applications of MWCNTs/TiO2Composite

“…TiO 2 is one of the most prominent oxide semiconductor materials due to its high photocatalytic activity, chemical stability, nontoxicity, physical properties, and low cost [2]. However, TiO 2 has some disadvantage such as low surface area and easy recombination of the electron-hole pair [3]. The photocatalytic activity of TiO 2 can be improved by reducing the electron-hole recombination rate, preventing the particles agglomeration, and increasing the adsorption capacity.…”

Photocatalytic Degradation of Anthracene in Closed System Reactor

“…Zinc oxide and titanium dioxide are universally considered as the most important photocatalysts due to their lower cost and their considerably low band gap energy (∼3.2 eV) [12]. Nanoparticles of titanium dioxide were considered to be more efficient than bulk powder in photocatalytic field [13]. Several previous works used titanium dioxide as catalyst for degradation of different organic pollutants [14][15][16].…”