Search results for "Deposit"

Core-shell Zn-doped TiO2-ZnO nanofibers fabricated via a combination of electrospinning and metal-organic chemical vapour deposition

2010

Zn-doped TiO2 nanofibers shelled with ZnO hierarchical nanoarchitectures have been fabricated combining electrospinning of TiO2 (anatase) nanofibers and metal-organic chemical vapor deposition (MOCVD) of ZnO. The proposed hybrid approach has proven suitable for tailoring both the morphology of the ZnO external shell as well as the crystal structure of the Zn-doped TiO2 core. It has been found that the Zn dopant is incorporated in calcined electrospun nanofibers without any evidence of ZnO aggregates. Effects of different Zn doping levels of Zn-doped TiO2 fibers have been scrutinized and morphological, structural, physico-chemical and optical properties evaluated before and after the hierarc…

Preparation and Characterization of Nanostructured Fe-TiO2 Thin Films Produced by Electrophoretic Deposition

2013

Fe-TiO2 thin films have been produced by a sol-electrophoretic deposition method on metallic Ti foil substrates. X-ray diffractograms and Raman spectra confirms the anatase structure of deposited and annealed Fe-TiO2 films. Obtained Fe-TiO2 thin films demonstrate photoactivity under visible light radiation due to the doping with Fe3+ ions. Open circuit potential results shows that increase of the film thickness and surface area improves the photoactivity of Fe-TiO2.

Structural Studies of Titanium Oxide Multilayers

2005

Multilayers of titanium oxide on conductive glasses (silica, covered with indium/tin and tin oxides) were obtained by different methods (from suspension, by sol–gel, by vacuum sputtering). X-ray diffraction and positron annihilation depth-resolved characterization of these samples are presented. The data allow us to determine optimal deposition parameters, in order to obtain the anatase phase, important in practical applications in photoelectrochemical cells.

Tailoring the Structural, Optical, and Photoluminescence Properties of Porous Silicon/TiO2 Nanostructures

2015

The structural, optical, and photoluminescence properties of porous silicon (PSi)/titanium dioxide (TiO2) nanostructures were investigated. PSi structures consisting of macro- and mesoporous layers were fabricated by metal-assisted chemical etching, and then TiO2 was introduced inside the PSi matrix using the atomic layer deposition technique. We performed scanning electron microscopy, transmission electron microscopy (TEM), X-ray diffraction, energy dispersive X-ray spectroscopy, Raman spectroscopy, ellipsometry, and photoluminescence (PL) spectroscopy to characterize the prepared and annealed PSi/TiO2 nanostructures. TEM and Raman analyses revealed that TiO2 had a crystalline anatase stru…

Black carbon-doped TiO2 films: Synthesis, characterization and photocatalysis

2019

This research is funded by the European Social Fund according to the activity ‘Improvement of researchers’ qualification by implementing world-class R&D projects’ of Measure No. 09.3.3-LMT- K-712, project „Investigation of the application of TiO2 and ZnO for the visible light assisted photocatalytical disinfection of the biologically contaminated water“ (09.3.3-LMT-K-712-01-0175). The authors express gratitude for the S. Tuckute, M. Urbonavicius, G. Laukaitis and K. Bockute for their valuable input in current work. © 2019. This work is licensed under a CC BY-NC-ND 4.0 license.

Electrochemical Investigation of Lithium Intercalation in MOCVD Derived Nanostructured Anatase/Rutile TiO2

2011

In this paper we report on the lithium reversible storage in titanium dioxide (TiO2) prepared by metal-organic chemical vapor deposition (MOCVD). Electrochemical properties in terms of lithium reversible insertion depend on the deposited microstructure. For thick films deposited on silicon wafer electrochemical activity of the anatase type of TiO2 is registered in the potential range 1.8-2.1 V vs. Li. For thinner films the intercalation reaction takes place in two potential ranges: 1.8-2.1 V vs. Li and below 1.4 V vs. Li. The second electroactivity range is attributed to lithium insertion into rutile. We found that the decrease of the lower potential limit (0.5 V instead of commonly used 1 …

Lateral Fusion of Chemical Vapor Deposited N = 5 Armchair Graphene Nanoribbons

2017

Bottom-up synthesis of low-bandgap graphene nanoribbons with various widths is of great importance for their applications in electronic and optoelectronic devices. Here we demonstrate a synthesis of N = 5 armchair graphene nanoribbons (5-AGNRs) and their lateral fusion into wider AGNRs, by a chemical vapor deposition method. The efficient formation of 10- and 15- AGNRs is revealed by a combination of different spectroscopic methods, including Raman and UV−visnear-infrared spectroscopy as well as by scanning tunneling microscopy. The degree of fusion and thus the optical and electronic properties of the resulting GNRs can be controlled by the annealing temperature, providing GNR films with o…

EFFECT OF ANNEALING PROCESS ON CIGS FILMS PREPARED BY ONE-STEP ELECTRODEPOSITION

2013

Ruthenium Oxide Nanotubes Via Template Electrosynthesis

2011

Ruthenium oxide nanotubes were fabricated by a single-step galvanostatic deposition using porous anodic alumina membrane as template. For the electrodeposition process, we used a electrochemical cell specifically designed in order to employ only 0.5 ml of 0.02 M RuCl3•xH2O solution. The deposition from a very small volume was specifically addressed owing to the high cost of ruthenium compounds, which could be of some relevance from an applicative point of view. Several techniques were used to characterize the samples prior to and after thermal treatment, which was carried out at different temperatures in order to study the crystallization process of the deposit. Raman spectroscopy of as-dep…

Structural and compositional analysis of anodic films on Al-Nb sputter-deposited alloys

2006

The photoelectrochemical behavior of anodic films on Al alloys, containing titanium, tantalum, and tungsten (valve metals), has been studied as a function of alloy composition and anodizing conditions. Photocurrent spectroscopy has been used to get information on bandgap and the flatband potential values of different mixed oxides. Both insulator-like and semiconducting behavior has been observed for anodic oxides grown on Al-W and Al-Ti alloys dependent on alloy initial composition. Optical bandgap values, Eg,opt, of different oxides are in accordance with predictions based on the correlation between Eg,opt and the difference of electronegativities of the oxide constituents, indicating pote…