Laser-Induced Chemical Liquid-Phase Deposition Plasmonic Gold Nanoparticles on Porous TiO2 Film with Great Photoelectrochemical Performance

This paper considers the photoelectrochemical characteristics of a composite porous TiO2 thin film with deposited plasmonic gold nanoparticles. The deposition of gold nanoparticles was carried out by the laser-induced chemical liquid-phase deposition (LCLD) method. The structural characteristics of the composite have been studied; it has been shown that the porous TiO2 film has a lattice related to the tetragonal system and is in the anatase phase. Gold nanoparticles form on the surface of a porous TiO2 film. A complex of photoelectrochemical measurements was carried out. It was shown that the deposition of plasmonic gold nanoparticles led to a significant increase in the photocurrent density by ~820%. The proposed concept is aimed at testing the method of forming a uniform layer of plasmonic gold nanoparticles on a porous TiO2 film, studying their photocatalytic properties for further scaling, and obtaining large area Au/TiO2/FTO photoelectrodes, including in the roll-to-roll process.

Atomic layer deposition for rutile structure TiO2 thin films using a SnO2 seed layer and low temperature heat treatment

We study the rutile-TiO2 film deposition with a high-k value using a SnO2 seed layer and a low temperature heat treatment. Generally, heat treatment over 600 ℃ is required to obtain the rutile-TiO2 film. However, By using a SnO2 seed layer, we obtained rutile-TiO2 films with heat treatments as low as 400 ℃. The XPS analysis confirms that the SnO2 and TiO2 film were deposited. The XRD analysis showed that a heat treatment at 400 ℃ after depositing the SnO2 and TiO2 films was effective in obtaining the rutile-TiO2 film when the SnO2 film was thicker than 10nm. The TEM / EDX analysis show that no diffusion in the thin film between TiO2 and SnO2. The dielectric constant of the TiO2 film deposited on the SnO2 film (20 nm) was 68, which was more than twice as high as anatase TiO2 dielectric constant. The current density was 10-4A/cm2 at 0.7 V and this value confirmed that the leakage current was not affected by the SnO2 seed layer.

Floating Carbon-Doped TiO2 Photocatalyst with Metallic Underlayers Investigation for Polluted Water Treatment under Visible-Light Irradiation

In the current study, we analysed the influence of metallic underlayers on carbon-doped TiO2 films for RhB decomposition and Salmonella typhimurium inactivation under visible-light irradiation. All the experiments were divided into two parts. First, layered M/C-doped-TiO2 film structures (M = Ni, Nb, Cu) were prepared by magnetron sputtering technique on borosilicate glass substrates in the two-step deposition process. The influence of metal underlayer on the formation of the carbon-doped TiO2 films was characterised by X-ray diffractometer, scanning electron microscope, and atomic force microscope. The comparison between the visible-light assisted photocatalytic activity of M/C-doped TiO2 structures was performed by the photocatalytic bleaching tests of Rhodamine B dye aqueous solution. The best photocatalytic performance was observed for Ni/C-doped-TiO2 film combination. During the second part of the study, the Ni/C-doped-TiO2 film combination was deposited on high-density polyethylene beads which were selected as a floating substrate. The morphology and surface chemical analyses of the floating photocatalyst were performed. The viability and membrane permeability of Salmonella typhimurium were tested in cycling experiments under UV-B and visible-light irradiation. Three consecutive photocatalytic treatments of fresh bacteria suspensions with the same set of floating photocatalyst showed promising results, as after the third 1 h-long treatment bacteria viability was still reduced by 90% and 50% for UV-B and visible-light irradiation, respectively. The membrane permeability and ethidium fluorescence results suggest that Ni underlayer might have direct and indirect effect on the bacteria inactivation process. Additionally, relatively low loss of the photocatalyst efficiency suggests that floating C-doped TiO2 photocatalyst with the Ni underlayer might be seen as the possible solution for the used photocatalyst recovery issue.