Photoluminescence and Photocatalytic Properties of Nanocrystalline TiO2:Tb Thin Films

2012 ◽  
Vol 18-19 ◽  
pp. 187-193 ◽  
Author(s):  
Damian Wojcieszak ◽  
Jaroslaw Domaradzki ◽  
Danuta Kaczmarek ◽  
Eugeniusz Prociow ◽  
Antoni W. Morawski ◽  
...  
Keyword(s):  
Thin Films ◽  
Photocatalytic Activity ◽  
Light Emission ◽  
Uv Light ◽  
High Energy ◽  
Tio2 Thin Films ◽  
Rutile Structure ◽  
The Matrix ◽  
Phenol Decomposition ◽  
Crystallite Sizes

In this work photoluminescence together with photocatalytic activity of nanocrystalline TiO2 thin films doped with different amount of Tb are described. Thin films were manufactured by high energy reactive magnetron sputtering process. Structural investigation has shown that all as-deposited films had rutile structure. Doping of the matrix resulted in decrease of the average crystallite sizes from 8.7 nm to 6.6 nm for undoped and doped films, respectively. This testifies about densification of the matrix structure by Tb-doping. Photoluminescence measurements of TiO2:Tb films have revealed light emission in wide spectral range (from 350 up to 700 nm) with a strong green luminescence at 545 nm. In order to explain Tb3+ luminescence phenomenon in TiO2-rutile matrix possible energy transfer mechanisms are discussed. The photocatalytic activity of nanocrystalline films was determined based on phenol decomposition during UV-light irradiation. Results showed that all manufactured films were photocatalytically active and their activity was growing with increase of terbium amount. The highest decomposition rate was observed for the TiO2 thin films with Tb amount of 2.6 at. %.

scholarly journals Influence of the structural and surface properties on photocatalytic activity of TiO2:Nd thin films

2015 ◽  
Vol 17 (2) ◽  
pp. 103-111 ◽  
Author(s):  
Damian Wojcieszak ◽  
Michał Mazur ◽  
Danuta Kaczmarek ◽  
Jerzy Morgiel ◽  
Agata Poniedziałek ◽  
...  
Keyword(s):  
Thin Films ◽  
Photocatalytic Activity ◽  
Magnetron Sputtering ◽  
Anatase Phase ◽  
High Energy ◽  
Columnar Structure ◽  
Photoluminescence Intensity ◽  
Rutile Structure ◽  
Phenol Decomposition ◽  
Titanium Dioxide Thin Films

Abstract Titanium dioxide thin films doped with the same amount of neodymium were prepared using two different magnetron sputtering methods. Thin films of anatase structure were deposited with the aid of Low Pressure Hot Target Magnetron Sputtering, while rutile coatings were manufactured using High Energy Reactive Magnetron Sputtering process. The thin films composition was determined by energy dispersive spectroscopy and the amount of the dopant was equal to 1 at. %. Structural properties were evaluated using transmission electron microscopy and revealed that anatase films had fibrous structure, while rutile had densely packed columnar structure. Atomic force microscopy investigations showed that the surface of both films was homogenous and consisted of nanocrystalline grains. Photocatalytic activity was assessed based on the phenol decomposition. Results showed that both thin films were photocatalytically active, however coating with anatase phase decomposed higher amount of phenol. The transparency of both thin films was high and equal to ca. 80% in the visible wavelength range. The photoluminescence intensity was much higher in case of the coating with rutile structure.

Influence of terbium on structure and luminescence of nanocrystalline TiO2 thin films

Open Physics ◽  
2013 ◽  
Vol 11 (2) ◽  
Author(s):  
Damian Wojcieszak ◽  
Danuta Kaczmarek ◽  
Jaroslaw Domaradzki ◽  
Anna Lukowiak ◽  
Wieslaw Strek
Keyword(s):  
Thin Films ◽  
High Energy ◽  
Optical Investigation ◽  
X Ray Diffraction ◽  
Tio2 Thin Films ◽  
Nanocrystalline Tio2 ◽  
Rutile Structure ◽  
Crystal Forms ◽  
The Matrix ◽  
Direct Energy

AbstractIn this work analysis of the structural and optical properties of TiO2 thin films doped with terbium has been described. Samples were prepared by a high energy reactive magnetron sputtering process under low pressure of oxygen plasma. X-ray diffraction results have shown that different TiO2 crystal forms have been produced, depending on the amount of Tb dopant. The undoped matrix had rutile structure with crystallites with a size of 8.7 nm, while incorporation of 0.4 at. % of Tb into the film during the sputtering process resulted in anatase structure with bigger crystallites (11.7 nm). Increasing the amount of terbium up to 2 at. % and 2.6 at. % gave rutile structure with crystallites with a size of 6.6 nm for both films. However, Raman spectroscopy has revealed that in the case of TiO2:(2 at. % Tb), except for the rutile form, the presence of fine-crystalline anatase was observed. Moreover, the lack of Raman peaks shift attests to the lack of stress in the titania lattice of all of the TiO2:Tb films. This fact indicates localization of Tb3+ ions on the surface of TiO2 nanocrystals. In the case of optical investigation, results have shown that doping with terbium has a significant influence on the properties of TiO2, but it does not decrease the high transparency of the matrix. The observed changes of the transmission characteristics were produced only due to modification of the TiO2:Tb structure. Photoluminescence measurements have shown that emission of light from TiO2:Tb films occurs when the amount of terbium is 2.6 at. %. Based on the obtained results a scheme of direct energy transfer from titanium dioxide matrix (with rutile structure) to Tb3+ ions has been proposed.

Photocatalytic properties of nanocrystalline TiO2 thin films doped with Tb

Open Physics ◽  
2011 ◽  
Vol 9 (2) ◽  
Author(s):  
Damian Wojcieszak ◽  
Danuta Kaczmarek ◽  
Jaroslaw Domaradzki ◽  
Eugeniusz Prociow ◽  
Antoni Morawski ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Photocatalytic Activity ◽  
High Energy ◽  
Photocatalytic Properties ◽  
Hydroxyl Groups ◽  
Reactive Magnetron ◽  
Tio2 Thin Films ◽  
Nanocrystalline Tio2 ◽  
Rutile Structure

AbstractIn this work photocatalytic properties of TiO2 thin films doped with different amount of Tb have been described. Thin films were prepared by high energy reactive magnetron sputtering process. Comparable photocatalytic activity has been found for all doped TiO2 thin films, while different amounts of Tb dopant (0.4 and 2.6 at. %) results in either an anatase or rutile structure. It was found that the terbium dopant incorporated into TiO2 was also responsible for the amount of hydroxyl groups and water particles adsorbed on the thin film surfaces and thus photocatalytic activity was few times higher in comparison with results collected for undoped TiO2 thin films.

Influence of nanocrystalline structure and composition on hardness of thin films based on TiO2

Open Physics ◽  
2011 ◽  
Vol 9 (2) ◽  
Author(s):  
Danuta Kaczmarek ◽  
Damian Wojcieszak ◽  
Jaroslaw Domaradzki ◽  
Eugeniusz Prociow ◽  
Frank Placido ◽  
...  
Keyword(s):  
Thin Films ◽  
Nanocrystalline Structure ◽  
High Energy ◽  
Pure Oxygen ◽  
Tio2 Thin Films ◽  
Nanocrystalline Tio2 ◽  
Rutile Structure ◽  
Undoped Tio2 ◽  
Crystallite Sizes ◽  
Tio2 Matrix

AbstractIn this work, the influence of Tb-doping on structure, and especially hardness of nanocrystalline TiO2 thin films, has been described. Thin films were formed by a high-energy reactive magnetron sputtering process in a pure oxygen atmosphere. Undoped TiO2-matrix and TiO2:Tb (2 at. % and 2.6 at. %) thin films, had rutile structure with crystallite sizes below 10 nm. The high-energy process produces nanocrystalline, homogenous films with a dense and close packed structure, that were confirmed by X-ray diffraction patterns and micrographs from a scanning electron microscope. Investigation of thin film hardness was performed with the aid of a nanoindentation technique. Results of measurements have shown that the hardness of all manufactured nanocrystalline films is above 10 GPa. In the case of undoped TiO2 matrix, the highest hardness value was obtained (14.3 GPa), while doping with terbium results in hardness decreasing down to 12.7 GPa and 10.8 GPa for TiO2:(2 at. % Tb) and TiO2:(2.6 at. % Tb) thin films, respectively. Incorporation of terbium into TiO2-matrix also allows modification of the elastic properties of the films.

scholarly journals Correlation of Photocatalysis and Photoluminescence Effect in Relation to the Surface Properties of TiO2:Tb Thin Films

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Damian Wojcieszak ◽  
Danuta Kaczmarek ◽  
Jaroslaw Domaradzki ◽  
Michal Mazur
Keyword(s):  
Thin Films ◽  
Photocatalytic Activity ◽  
Surface Properties ◽  
High Energy ◽  
Rutile Structure ◽  
Current State ◽  
Wide Range ◽  
First Time ◽  
The Relationship ◽  
Deposited Films

In this paper structural, optical, photoluminescence, and photocatalytic properties of TiO2and TiO2:(2.6 at. % Tb) thin films have been compared. Thin films were prepared by high-energy reactive magnetron sputtering process, which enables obtaining highly nanocrystalline rutile structure of deposited films. Crystallites sizes were 8.7 nm and 6.6 nm for TiO2and TiO2:Tb, respectively. Surface of prepared thin films was homogenous with small roughness of ca. 7.2 and 2.1 nm in case of TiO2and TiO2:Tb samples, respectively. Optical properties measurements have shown that the incorporation of Tb into TiO2matrix has not changed significantly the thin films transparency. It also enables obtaining photoluminescence effect in wide range from 350 to 800 nm, what is unique phenomenon in case of TiO2with rutile structure. Moreover, it has been found that the incorporation of 2.6 at. % of Tb has increased the photocatalytic activity more than two times as compared to undoped TiO2. Additionally, for the first time in the current state of the art, the relationship between photoluminescence effect, photocatalytic activity, and surface properties of TiO2:Tb thin films has been theoretically explained.

Hardness of Nanocrystalline TiO2 Thin Films

2012 ◽  
Vol 18-19 ◽  
pp. 195-200 ◽  
Author(s):  
Danuta Kaczmarek ◽  
Jaroslaw Domaradzki ◽  
Damian Wojcieszak ◽  
Eugeniusz Prociow ◽  
Michal Mazur ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Low Pressure ◽  
High Energy ◽  
Film Structure ◽  
Tio2 Thin Films ◽  
Nanocrystalline Tio2 ◽  
Rutile Structure ◽  
Tio2 Anatase ◽  
Additional Annealing

In this work results of hardness investigations of nanocrystalline TiO2 thin films are presented. Thin films were prepared by low pressure hot target reactive sputtering (LPHTRS) and high energy reactive magnetron sputtering (HERMS). In both processes a metallic Ti target was sputtered under low pressure of oxygen working gas. After deposition by LPHTRS TiO2 thin films with anatase structure were obtained and after additional post-process annealing at 1070 K, these films recrystallized into the rutile structure. Annealing also resulted in an increase of average crystallite size from 33 nm (for anatase) to 74 nm (for rutile). The HERMS process is a modification of the LPHTRS process with the addition of an increased amplitude of unipolar voltage pulses, powering the magnetron. This effectively increases the total energy of the depositing particles at the substrate and allows dense, nanocrystalline (8.7 nm crystallites in size) TiO2 thin film with the rutile structure to be formed directly. The hardness of the films was determined by nanoindentation. The results showed that the nanocrystalline TiO2-rutile thin film as-deposited using HERMS had high hardness (14.3 GPa), while the TiO2-anatase films as-deposited by LPHTRS, were 4-times lower (3.5 GPa). For LPHTRS films recrystallized by additional annealing, the change in thin film structure from anatase to rutile resulted in an increase of film hardness from 3.5 GPa to only 7.9 GPa. The HERMS process can therefore produce the TiO2 rutile structure directly, with hardness that is 2 times greater than rutile films produced by LPHTRS with additional annealing step.

scholarly journals Au-Ag/TiO2 Thin Films Preparation by Laser Ablation and Sputtering Plasmas for Its Potential Use as Photoanodes in Electrochemical Advanced Oxidation Processes (EAOP)

Catalysts ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1406
Author(s):  
Luis Alejandro Martínez-Chávez ◽  
Eric Mauricio Rivera-Muñoz ◽  
Rodrigo Rafael Velázquez-Castillo ◽  
Luis Escobar-Alarcón ◽  
Karen Esquivel
Keyword(s):  
Thin Films ◽  
Photocatalytic Activity ◽  
Laser Ablation ◽  
Uv Light ◽  
Average Crystallite Size ◽  
X Ray Diffraction ◽  
Tio2 Thin Films ◽  
Electric Voltage ◽  
Electrochemical Advanced Oxidation Processes ◽  
Compound Model

Titanium dioxide (TiO2) is widely used, studied, and synthesized using different methodologies. By a modification of the material, it can be applied to wastewater treatment. A combined sputtering-laser ablation setup was used to deposit TiO2 thin films modified, individually and simultaneously, with gold (Au) and silver (Ag). To investigate the effect of the metal incorporation in titanium and its impact on the photocatalytic activity, with dye discoloration as a pollutant compound model, the deposited films were characterized by UV–Vis, photoluminescence, and Raman spectroscopies, as well as by parallel beam X-ray diffraction. The results showed that films with different Au and Ag loads, and an 18 nm average crystallite size, were obtained. These metals have an essential effect on the deposited film’s compositional, structural, and optical properties, directly reflected in its photocatalytic activity. The photocatalytic test results using UV-Vis showed that, after 1 h of applying a 4.8 V electric voltage, a discoloration of up to 80% of malachite green (MG) was achieved, using ultraviolet (UV) light.

Photocatalytic degradation of methylene blue from aqueous solutions using nanopillars-TiO2 thin films: Batch reactor studies

2018 ◽  
Vol 18 (3) ◽  
pp. 81-91 ◽  
Author(s):  
C. Lalhriatpuia
Keyword(s):  
Thin Films ◽  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Organic Carbon ◽  
Photocatalytic Degradation ◽  
Batch Reactor ◽  
Tio2 Thin Films ◽  
Initial Concentration ◽  
Bet Specific Surface Area ◽  
Interfering Ions

Nanopillars-TiO2 thin films was obtained on a borosilicate glass substrate with (S1) and without (S2) polyethylene glycol as template. The photocatalytic behaviour of S1 and S2 thin films was assessed inthe degradation of methylene blue (MB) dye from aqueous solution under batch reactor operations. The thin films were characterized by the SEM, XRD, FTIR and AFM analytical methods. BET specific surface area and pore sizes were also obtained. The XRD data confirmed that the TiO2 particles are in its anatase mineral phase. The SEM and AFM images indicated the catalyst is composed with nanosized pillars of TiO2, evenly distributed on the surface of the substrate. The BET specific surface area and pore sizes of S1 and S2 catalyst were found to be 5.217 and 1.420 m2/g and 7.77 and 4.16 nm respectively. The photocatalytic degradation of MB was well studied at wide range of physico-chemical parameters. The effect of solution pH (pH 4.0 to 10.0) and MB initial concentration (1.0 to 10.0 mg/L) was extensively studied and the effect of several interfering ions, i.e., cadmium nitrate, copper sulfate, zinc chloride, sodium chloride, sodium nitrate, sodium nitrite, glycine, oxalic acid and EDTA in the photocatalytic degradation of MB was demonstrated. The maximum percent removal of MB was observed at pH 8.0 beyond which it started decreasing and a low initial concentration of the pollutant highly favoured the photocatalytic degradation using thin films and the presence of several interfering ions diminished the photocatalytic activity of thin films to some extent. The overall photocatalytic activity was in the order: S2 > S1 > UV. The photocatalytic degradation of MB was followed the pseudo-first-order rate kinetics. The mineralization of MB was studied with total organic carbon measurement using the TOC (total organic carbon) analysis.

STRUCTURAL, OPTICAL PROPERTIES AND PHOTOCATALYTIC ACTIVITY OF NANOCRYSTALLINE TiO2 THIN FILMS DEPOSITED BY SOL-GEL SPIN COATING

2019 ◽  
Vol 7 (1) ◽  
pp. 28
Author(s):  
KOMARAIAH DURGAM ◽  
RADHA EPPA ◽  
REDDY M. V. RAMANA ◽  
KUMAR J. SIVA ◽  
R. SAYANNA ◽  
...  
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Photocatalytic Activity ◽  
Spin Coating ◽  
Sol Gel ◽  
Tio2 Thin Films ◽  
Nanocrystalline Tio2

Use of Nanopillars-TiO2 Thin Films in the Photocatalytic Degradation of Bromophenol Blue from Aqueous Solution

2018 ◽  
Vol 6 (1) ◽  
pp. 22-30
Author(s):  
C. Lalhriatpuia ◽  
◽  
Thanhming liana ◽  
K. Vanlaldinpuia
Keyword(s):  
Thin Films ◽  
Aqueous Solution ◽  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Batch Reactor ◽  
Bromophenol Blue ◽  
Tio2 Thin Films ◽  
Initial Concentration ◽  
Bet Specific Surface Area ◽  
Interfering Ions

The photocatalytic activity of Nanopillars-TiO2 thin films was assessed in the degradation of Bromophenol blue (BPB) dye from aqueous solution under batch reactor operations. The thin films were characterized by the XRD, SEM and AFM analytical methods. BET specific surface area and pore sizes were also obtained. The XRD data showed anatase phase of TiO2 particles with average particle size of 25.4 and 21.9 nm, for S1 and S2 catalysts respectively. The SEM and AFM images indicated the catalyst composed with Nanosized pillars of TiO2, evenly distributed on the surface of the substrate. The average height of the pillars was found to be 180 and 40 nm respectively for the S1 and S2 catalyst. The BET specific surface area and pore sizes of S1 and S2 catalyst were found to be 5.217 and 1.420 m2/g and 7.77 and 4.16 nm respectively. The photocatalytic degradation of BPB using the UV light was studied at wide range of physico-chemical parametric studies to determine the mechanism of degradation as well as the practical applicability of the technique. The batch reactor operations were conducted at varied pH (pH 4.0 to 10.0), BPB initial concentration (1.0 to 20.0 mg/L) and presence of several interfering ions, i.e., cadmium nitrate, copper sulfate, zinc chloride, sodium chloride, sodium nitrate, sodium nitrite, glycine, oxalic acid and EDTA in the photocatalytic degradation of BPB. The maximum percent removal of BPB was observed at pH 6.0 and a low initial concentration of the pollutant highly favours the photocatalytic degradation using thin films. The presence of several interfering ions suppressed the photocatalytic activity of thin films to some extent. The time dependence photocatalytic degradation of BPB was demonstrated with the pseudo-first-order rate kinetics. Study was further extended with total organic carbon measurement using the TOC (Total Organic Carbon) analysis. This demonstrated an apparent mineralization of BPB from aqueous solutions.

Sign in / Sign up

Export Citation Format

Share Document