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.

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.

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.

scholarly journals The Growth of Semiconductor Thin Films Studied by RHEED

1990 ◽  
Vol 43 (5) ◽  
pp. 583
Author(s):  
GL Price
Keyword(s):  
Thin Films ◽  
Surface Science ◽  
High Vacuum ◽  
High Energy ◽  
Ultra High Vacuum ◽  
Large Area ◽  
Growth Modes ◽  
Semiconductor Thin Films ◽  
Wide Range ◽  
Recent Developments

Recent developments in the growth of semiconductor thin films are reviewed. The emphasis is on growth by molecular beam epitaxy (MBE). Results obtained by reflection high energy electron diffraction (RHEED) are employed to describe the different kinds of growth processes and the types of materials which can be constructed. MBE is routinely capable of heterostructure growth to atomic precision with a wide range of materials including III-V, IV, II-VI semiconductors, metals, ceramics such as high Tc materials and organics. As the growth proceeds in ultra high vacuum, MBE can take advantage of surface science techniques such as Auger, RHEED and SIMS. RHEED is the essential in-situ probe since the final crystal quality is strongly dependent on the surface reconstruction during growth. RHEED can also be used to calibrate the growth rate, monitor growth kinetics, and distinguish between various growth modes. A major new area is lattice mismatched growth where attempts are being made to construct heterostructures between materials of different lattice constants such as GaAs on Si. Also described are the new techniques of migration enhanced epitaxy and tilted superlattice growth. Finally some comments are given On the means of preparing large area, thin samples for analysis by other techniques from MBE grown films using capping, etching and liftoff.

scholarly journals ASSESSMENT OF THE CURRENT STATE OF COASTAL WATERS OF THE SOUTHERN PART OF LAKE BAIKAL ON SANITARY AND MICROBIOLOGICAL INDICATORS WITH USE OF THE TEST SYSTEMS

2018 ◽  
pp. 54-58
Author(s):  
I.V. Mosharova ◽  
V.V. Il’inskij ◽  
O.V. Il’ina
Keyword(s):  
Lake Baikal ◽  
Coastal Waters ◽  
Test Systems ◽  
Current State ◽  
Wide Range ◽  
Microbial Number ◽  
Southern Site ◽  
First Time ◽  
Number Of Bacteria ◽  
Microbiological Indicators

Sanitary and microbiological researches of a coastal surface water of the southern part of Lake Baikal (from the Listvyanka to the Tanghui) were conducted in June, 2017. Total number of bacteria varied over a wide range – from 0.93 million сells/ml up to 2:05 million сells/ml, with an average 1.41 ± 0.3 million сells/ml. Biomass of bacteria varied from 11.05 to 305.00 mg С/m3, with an average of 123.34 mg С/m3. Coastal waters of the southern site of Lake Baikal mainly had a beta-meso-saprobic status in June, 2017. The total microbial number was determined with the use of the test systems for the first time. The values of the total microbial number were less than 1 000 COU/ml and varied from 9 to 412 COU/ml. Innovative test systems Petrifilm are of great interest for rapid assessments of the sanitary and microbiological status of reservoirs directly in the field conditions.

Controllable growth of novel BiPO4 dendrites by an innovative approach and high energy facets-dependent photocatalytic activity

CrystEngComm ◽  
2014 ◽  
Vol 16 (36) ◽  
pp. 8334-8339 ◽  
Author(s):  
Qiuying Zhang ◽  
Hao Tian ◽  
Na Li ◽  
Mindong Chen ◽  
Fei Teng
Keyword(s):  
Photocatalytic Activity ◽  
High Energy ◽  
Innovative Approach ◽  
Tetraacetic Acid ◽  
Ethylenediamine Tetraacetic Acid ◽  
Controllable Growth ◽  
First Time

Two new monoclinic BiPO4 nanodendrites were for the first time hydrothermally synthesized in the presence of ethylenediamine-tetraacetic acid.

scholarly journals Surface morphology and X-ray photoelectron spectroscopy of BiFeO3 thin films deposited on top of Ta2O5/Si layers

2021 ◽  
Vol 295 ◽  
pp. 04009
Author(s):  
Shikhgasan Ramazanov ◽  
Ştefan Ţălu ◽  
Rashid Dallaev ◽  
Guseyn Ramazanov ◽  
Pavel Škarvada ◽  
...  
Keyword(s):  
Thin Films ◽  
Photoelectron Spectroscopy ◽  
Bismuth Ferrite ◽  
Ferrite Film ◽  
Bifeo3 Thin Films ◽  
Expansion Coefficients ◽  
The Difference ◽  
First Time ◽  
The Relationship

In this study a comparison of the topography of BiFeO3 (BFO) thin films deposited on tantalum pentoxide substrates of different thicknesses is provided. The Ta2O5 substrates had a roughness increasing with the film thickness. The relationship between substrates of different topography but the same composition with the quality of the growing bismuth ferrite film is estimated. For the first time the topography estimation of BFO on Ta2O5 is presented. The difference in temperature expansion coefficients leads to intensive evaporation of bismuth ferrite from the surface during annealing. XPS analysis is provided for asdeposited and annealed BFO layers.

scholarly journals The Grain Market between the Reigns of Alexey Mikhailovich and Catherine the Great: Was there a ‘Price Revolution’?

2021 ◽  
Vol 9 (3) ◽  
Author(s):  
Arthur Mustafin
Keyword(s):  
Eighteenth Century ◽  
Supply And Demand ◽  
Wide Range ◽  
Grain Market ◽  
The Impact ◽  
First Time ◽  
The Relationship ◽  
Regions Of Russia ◽  
Grain Prices

The author of this article attempts to reveal and systematise archival data on grain prices in Russia between the 1650s and 1700s and analyse their dynamics by comparing them with data for the eighteenth century. The study is based on a wide range of archival sources from the funds of the RSAAA (RGADA), CSA of Moscow (TsGA of Moscow), DM NLR (OR RNB), and SFI CANNR (GKU TsANO). The data from these sources make it possible to construct time series describing rye and oat price dynamics in the northern and central non-black earth regions of Russia. The author substantiates the homogeneity and reliability of the data received and determines the real prices. The resulting numbers make the author doubt the “price revolution” in eighteenth-century Russia. Throughout the eighteenth century, the average real prices remained below the level of the 1660s and 1670s. Only in the 1790s did prices briefly exceed this level. Overall, the Russian grain market was characterised by long-term price fluctuations. The author aims to explain this dynamic by analysing supply and demand in the grain market. More particularly, for the first time in the historiography, the author examines the connection between Russian grain prices and yield in the second half of the seventeenth and eighteenth centuries. It is established that in most cases, the relationship between these indicators was direct: as grain yield increased, prices did too. The article explains this seeming paradox. The data published by the author help not only to estimate the impact of various factors on grain prices during the period in question, but also solve practical tasks regarding various price indicators in grain equivalents.

Metal Ion Complexes with Pyrazoles, Aziridines and Diaziridines – Synthesis and Biological Activity

2019 ◽  
Vol 26 (4) ◽  
pp. 648-663 ◽  
Author(s):  
Katarzyna Malinowska ◽  
Ingo-Peter Lorenz ◽  
Beata Sadowska ◽  
Paulina Mucha
Keyword(s):  
Biological Activity ◽  
Metal Ion ◽  
Biological Significance ◽  
Antimicrobial Properties ◽  
Transition Metal Ions ◽  
Antitumor Action ◽  
Metal Ion Complexes ◽  
Current State ◽  
Wide Range ◽  
The Relationship

Heterocyclic compounds containing nitrogen ions, like pyrazoles, aziridines, diaziridines and their metal ion complexes with Cu(II), Zn(II) and Ru(III) and others exhibit a wide range of biological activity, including mainly anti-inflammatory, antioxidant, anticancer, and antimicrobial properties. Biological significance of these molecules and thus their potential use in medicine has driven growing interest into their coordination chemistry. A knowledge of the relationship between the structure of chemical compounds and their activity is needed for the synthesis of the preparations possessing the most beneficial features. The choice of interposed substituents may improve biocidal and antitumor action, reduce the toxicity of the initial substance, or even completely eliminate its adverse effects for healthy tissues. The main aim of this review paper is to present the current state of knowledge concerning the synthesis and biological activity of complexes with small heterocyclic ligands containing transition metal ions.

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