Photostability and optical properties of modified titanium dioxide

2012 ◽  
Vol 84 (12) ◽  
pp. 2531-2547 ◽  
Author(s):  
Marta Gleń ◽  
Barbara Grzmil
Keyword(s):  
Titanium Dioxide ◽  
Optical Properties ◽  
Considerable Increase ◽  
Xrd Analysis ◽  
Selective Leaching ◽  
X Ray Diffraction ◽  
Gray Tone ◽  
Rutile Titanium Dioxide ◽  
Selective Leaching Method ◽  
Enhanced Photostability

The influence of different modifiers, P2O5, K2O, Al2O3, SiO2, CeO2, and ZrO2, on the optical properties and photostability of rutile titanium dioxide was studied. The research was aimed at obtaining pigmentary rutile titanium dioxide with the enhanced photostability. The optical properties such as brightness, white tone, and gray tone were improved when titanium dioxide samples were modified with zirconium instead of cerium. Titanium dioxide products modified additionally with Al2O3 displayed improved optical properties by comparison with appropriate titanium dioxide products lacking introduced aluminum. In comparison with unmodified material (∆E* = 21.8), a considerable increase of the photostability of modified titanium dioxide was observed. The lowest photoactivity, in the range of ∆E* = 0.96–2.45, was measured for the TiO2-PKAlSiCe series. A selective leaching method and X-ray diffraction (XRD) analysis were used to determine the distribution of modifiers in titanium dioxide materials. It was concluded that the differences in both photoactivity and optical properties of modified titanium dioxide depend on its phase composition.

Pigmentary properties of rutile TiO2 modified with cerium, phosphorus, potassium, and aluminium

2013 ◽  
Vol 67 (11) ◽  
Author(s):  
Marta Gleń ◽  
Barbara Grzmil
Keyword(s):  
Titanium Dioxide ◽  
Optical Properties ◽  
Photocatalytic Activity ◽  
Phase Composition ◽  
Xrd Analysis ◽  
Transformation Rate ◽  
Selective Leaching ◽  
P2o5 Content ◽  
Selective Leaching Method ◽  
Hydrated Titanium

AbstractThe influence of different modifiers, phosphorus, potassium, aluminium, and cerium on the pigmentary properties of TiO2 was studied. The phase composition and distribution of modifiers in prepared TiO2 products was investigated using XRD analysis, the selective leaching method, and ICP-AES technique. The optical properties, photoactivity, morphology, and surface area of modified TiO2 were determined by spectrophotometric, fluorescent, SEM, and BET measurements. The research was directed towards obtaining a pigmentary TiO2 with the highest possible photostability. It was found that the final calcination temperature, at which the anatase-rutile transformation rate was > 97 %, depended on the kind and amount of the modifiers introduced into hydrated titanium dioxide. In comparing the colour of TiO2 products modified with Ce, it was found that the addition of K to the TiO2 series caused an increase in all the optical properties examined. The presence of K and Al in TiO2 modified with Ce resulted in decreased photocatalytic activity. The photostability of TiO2 modified with Ce and K improved with an increase in P2O5 content. The highest photostability was measured for the TiO2-CePKAl series. It was concluded that the differences in both the optical properties and photoactivity of TiO2 depended on its phase composition and the distribution of modifiers in the products obtained.

Effect of CeO2 and Sb2O3 on the phase transformation and optical properties of photostable titanium dioxide

2011 ◽  
Vol 65 (2) ◽  
Author(s):  
Marta Gleń ◽  
Barbara Grzmil ◽  
Joanna Sreńscek-Nazzal ◽  
Bogumił Kic
Keyword(s):  
Phase Transformation ◽  
Titanium Dioxide ◽  
Optical Properties ◽  
Rutile Phase ◽  
Spectrophotometric Analysis ◽  
Grey Tone ◽  
Rutile Titanium Dioxide ◽  
Selective Leaching Method ◽  
Tio2 Phase ◽  
Xrd Method

AbstractIn the present work, the effect of individual additives calculated as molar fractions of Sb2O3 and CeO2 (x Sb 2O3 range: 0.03–0.08 %, x CeO 2 range: 0.05–0.14 %), on the phase composition, phase transformation, and optical properties of photostable rutile titanium dioxide was studied using selective leaching method, ICP-AES technique, XRD method, spectrophotometric analysis and S BET measurements. The starting material was hydrated titanium dioxide. It was observed that the addition of Sb2O3 to TiO2 did not influence the anatase-rutile phase transformation, but increasing the CeO2 addition caused a decrease in the rutilization degree. Thus, CeO2 acted as an inhibitor of the TiO2 phase transformation. Sb2O3 addition to TiO2 presumably caused the formation of a co-phase of Sb with Ti. Cerium formed a separate phase, CeO2, and reacted partly with titanium, probably creating co-phase, Ce0.8Ti0.2O2. Comparing the colour of modified rutile titanium dioxide according to the type of the additive introduced, it was found that TiO2 with CeO2 had higher brightness but lower white tone values when compared with TiO2 modified with Sb2O3. The relative lightening power and grey tone of the modified TiO2 were higher in TiO2 modified with Sb2O3. The values of the photocatalytic activity measured in all TiO2 samples modified either with Sb2O3 or CeO2 were very similar and varied around the value of 21.

scholarly journals Synthesis of Zinc Oxide Supported on Titanium Dioxide for Photocatalytic Oxidative Desulfurization of Dibenzothiophene

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Hitam, C.N.C. ◽  
Jalil, A.A. ◽  
Triwahyono, S.
Keyword(s):  
Zinc Oxide ◽  
Titanium Dioxide ◽  
High Efficiency ◽  
Diffuse Reflectance Spectroscopy ◽  
Anatase Phase ◽  
Oxidative Desulfurization ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Desulfurization Rate ◽  
Low Energy Consumption

Photocatalytic oxidative desulfurization (PODS) has received much attention due to low energy consumption and high efficiency, as well as simple and pollution-free operation. In this study, zinc oxide supported on titanium dioxide (ZnO/TiO2) catalysts were prepared via a simple electrochemical method. The presence of anatase phase TiO2 and wurtzite ZnO was confirmed by X-ray diffraction (XRD) analysis while band gap energies were determined by UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS). The photocatalytic activity was tested for desulfurization of 100 mg/L dibenzothiophene (DBT). The highest desulfurization rate (2.20 × 10-3 mM/min) was achieved using 1 g/L of 10 wt% ZnO/TiO2 after 2 hr under UV irradiation.

Synthesis and Optical Properties of Eu3+ Doped NaYF4 and KYF4 Micro/Nanocrystals

2016 ◽  
Vol 16 (4) ◽  
pp. 3857-3860 ◽  
Author(s):  
Siling Guo ◽  
Chunyan Cao ◽  
Renping Cao
Keyword(s):  
Optical Properties ◽  
Emission Spectra ◽  
Local Environment ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Two Samples ◽  
Xrd Patterns ◽  
The Eu

Through a hydrothermal method, 1 mol% Eu3+ doped NaYF4 and KYF4 micro/nanocrystals have been synthesized. The materials were characterized by X-ray diffraction (XRD) patterns, field emission scanning electron microscopy (FE-SEM) images, room temperature photoluminescence (PL) excitation and emission spectra, and luminescent dynamic decay curves. The XRD analysis suggested the crystalline structures of the obtained samples. The FE-SEM images indicated the morphology and size of the obtained samples. The PL spectra illustrate the optical properties of Eu3+ in the two samples. Since it is sensitive to the local environment of the ion, the Eu3+ presents different optical properties in the NaYF4 and KYF4 materials.

Structural and Optical Properties of SnO2 Films Grown on 6H-SiC by MOCVD

2009 ◽  
Vol 79-82 ◽  
pp. 1539-1542
Author(s):  
Zhen Zhu ◽  
Jin Ma ◽  
Cai Na Luan ◽  
Fan Yang ◽  
Ling Yi Kong
Keyword(s):  
Optical Properties ◽  
Chemical Vapor ◽  
Xrd Analysis ◽  
Visible Range ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
Rutile Structure ◽  
Average Transmittance ◽  
Sno2 Thin Films ◽  
Relationship Of

SnO2 thin films have been deposited on 6H-SiC(0001) substrates by metalorganic chemical vapor deposition (MOCVD) system. The structural and optical properties of SnO2 films were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and spectrophotometry. The XRD analysis revealed that the prepared samples were SnO2 epitaxial films of rutile structure with a clear relationship of SnO2(100)// 6H-SiC(0001). The average transmittance for the deposited SnO2 samples in the visible range was about 60%.

Optical and photocatalytic properties of photoactive paper with polycrystalline TiO2 nanopigment for optimal product design

TAPPI Journal ◽  
2012 ◽  
Vol 11 (5) ◽  
pp. 33-38 ◽  
Author(s):  
SEONGHYUK KO ◽  
PAUL D. FLEMING ◽  
MARGARET JOYCE ◽  
PNINA ARI-GUR
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Gas Chromatography ◽  
Titanium Dioxide ◽  
Optical Properties ◽  
Photocatalytic Activity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Optimal Product Design

We investigated the effect of the crystalline phases of titanium dioxide nanopigment to optimize the optical properties and photocatalytic activity for synthesizing a photoactive paper. Six different ratios of anatase to rutile were prepared. Phase change and particle size were characterized using X-ray diffraction and transmission electron microscopy. Optical properties including opacity and brightness were tested. Photocatalytic activity was evaluated by measuring toluene decomposition, using gas chromatography. A specific ratio between two different crystallites of titanium dioxide showed relatively better optical and photoactive properties. The optimal anatase-to-rutile ratio was found to be 0.52:0.48.

Synthesis of Rutile Titanium Dioxide Whiskers by Flux Method

2013 ◽  
Vol 711 ◽  
pp. 3-7
Author(s):  
Li Hua Zhang ◽  
Xue Ying Nai ◽  
Dong Hai Zhu ◽  
Cheng Cai Zhu ◽  
Xing Ru Zhang ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Growth Mechanism ◽  
Raw Material ◽  
X Ray Diffraction ◽  
Flux Method ◽  
X Ray ◽  
Scanning Electron Microcopy ◽  
Rutile Titanium Dioxide ◽  
Calcined Temperature ◽  
Scanning Electron

Rutile titanium dioxide whiskers with diameter around 2μm and length up to 45μm have been successfully synthesized via a facile flux method, using anatase titanium dioxide as raw material and a mixture of ZnSO47H2O and Na2SO4 as flux. The products were characterised by X-ray diffraction (XRD), scanning electron microcopy (SEM) and energy dispersive spectroscopy (EDS). It turned out that the calcined temperature and the type of flux addition affected the crystal phase and morphology of the final product greatly. The results showed that rutile titanium dioxide whiskers obtained at 850 °C for 4 hours had the most uniform morphology. The possible growth mechanism was briefly discussed.

Effects of misfit strain on properties of ZnO films grown by pulsed laser deposition

2001 ◽  
Vol 696 ◽  
Author(s):  
M.C. Park ◽  
W.H. Yoon ◽  
D.H. Lee ◽  
J.M. Myoung ◽  
S.H. Bae ◽  
...  
Keyword(s):  
Optical Properties ◽  
Film Thickness ◽  
Pulsed Laser Deposition ◽  
Pulsed Laser ◽  
Xrd Analysis ◽  
Misfit Strain ◽  
Laser Deposition ◽  
Zno Films ◽  
X Ray Diffraction ◽  
Electrical And Optical Properties

AbstractA series of ZnO films with various thicknesses were prepared on (0001) sapphire substrate by pulsed laser deposition (PLD). Scanning electron microscopy (SEM) and x-ray diffraction (XRD) analysis were utilized to investigate the effects of misfit strain on the surface morphology and the crystallinity. The electrical and optical properties of the films were also investigated as a function of the film thickness. It was found that the crystalline quality, electrical and optical properties of the films depended on the film thickness and were improved with increasing the film thickness. This is attributed to the fact that the films thinner than 400 nm are under the severe misfit strain, which decreases as the film thickness increases further.

SYNTHESIS AND CHARACTERIZATION OF SPHERE-LIKE ZnS NANOCRYSTALS BY THERMOLYSIS OF A NEW COMPLEX PRECURSOR

2010 ◽  
Vol 24 (19) ◽  
pp. 2091-2099 ◽  
Author(s):  
JIANJUN ZHANG ◽  
JUNHONG DUAN
Keyword(s):  
Optical Properties ◽  
Photoelectron Spectroscopy ◽  
Inorganic Compounds ◽  
Xrd Analysis ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nitrogen Stream ◽  
Zns Nanocrystals

In this paper, the preparation and optical properties of sphere-like ZnS nanocrystals are reported. Pure and uniform cubic-phase sphere-like ZnS nanocrystals with grain sizes of 30–40 nm were synthesized by thermolysis of a new precursor complex ( enH 2)0.5[ Zn ( en )3]( SCN )3 (en = ethylenediamine) in nitrogen stream at 800°C. The as-synthesized products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS), respectively. The XRD analysis reveals the phase of ZnS with cubic zinc blende. UV-Vis and photoluminescence spectra (PL) were utilized to investigate the optical properties of sphere-like ZnS nanocrystals. By testing on UV-Vis spectra, it is concluded that the limiting wavelength of the ZnS nanocrystals is 320 nm and the band gap is 3.88 eV. In room temperature PL spectra, one strong emission peak centered at 322 nm is discovered, which could be attributed to the band to band transitions. The above-mentioned results showed that the thermolysis method is preferable for synthesizing high-quality sphere-like ZnS nanocrystals. The synthesized precursor could be used as morphological templates to prepare nanostructure inorganic compounds.

Sign in / Sign up

Export Citation Format

Share Document