The Behavior of a TiO2 Nanoparticle under Extreme Conditions

2012 ◽  
Vol 1442 ◽  
Author(s):  
J. E. Lowther
Keyword(s):  
Distribution Function ◽  
Anatase Phase ◽  
Tio2 Nanoparticle ◽  
Nano Particles ◽  
Extreme Conditions ◽  
Nano Structures ◽  
Partial Distribution Function ◽  
Partial Distribution

ABSTRACTCompressibility of anatase nano particles of TiO2 changes from the bulk counterpart. This has been associated with amorphization and compaction. The behavior of such systems under extreme conditions is examined using a shell partial distribution function and some comparison made with rutile and baddeylite polytypes based nano structures. Particle energies of rutile and baddeylite nano particles appear to be rather size independent as compared to the anatase polytypes. The latter is associated with large relaxations and re-bonding in the relatively soft anatase phase of nano TiO2.

Influence of Preparation Methods of TiO2 Nano-Particle on Photodegradation of Methylene Blue

2020 ◽  
Vol 998 ◽  
pp. 84-89
Author(s):  
Jittinat Sirichokthanasarp ◽  
Dang Trung Tri Trinh ◽  
Du Ang Dao Channei ◽  
Kantapat Chansaenpak ◽  
Wilawan Khanitchaidecha ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Hydrothermal Method ◽  
Organic Compounds ◽  
High Efficiency ◽  
Anatase Phase ◽  
Sol Gel ◽  
Nano Particles ◽  
Preparation Methods ◽  
Gel Method ◽  
Sol Gel Method

The dye-pigments and organic compounds are known as significant pollutants in wastewater of textile industrial. Among of treatment technologies, the photocatalysis using TiO2 nano particles has potential on-site process for removing the dye-pigments and organic compounds, due to no hazardous waste and inexpensive. In this work, the TiO2 nanoparticles were synthesized by two different methods of hydrothermal and sol-gel. Nanoparticle of TiO2 synthesized by hydrothermal method contained pure anatase phase as similar as the TiO2 nanoparticles synthesized by sol-gel method. However, the TiO2 synthesized by hydrothermal method provided the higher specific surface area and pore volume rather than the another TiO2. Further, the high efficiency 86% of methylene blue photodegradation was observed during the by using TiO2 synthesized by hydrothermal method as photocatalyst, whereas the efficiency was only 72% for TiO2 synthesized by sol-gel method.

Variable Temperature Study of Au and Au-Pt Nanoparticles on Selected Oxide Supports

2010 ◽  
Vol 1279 ◽  
Author(s):  
D. Barrett ◽  
P. Franklyn ◽  
M. Scurrell
Keyword(s):  
Particle Size ◽  
Variable Temperature ◽  
Anatase Phase ◽  
Pt Nanoparticles ◽  
Ammonium Hydroxide ◽  
Nano Particles ◽  
Oxide Supports ◽  
Temperature Range ◽  
Size Relationship ◽  
Relationship Of

AbstractWe report on the size relationship of Au and Au-Pt nanoparticles that were synthesised on silica and anatase phase titania supports. Deposition-precipitation (DP) of metal chlorides with the addition of urea and ammonium hydroxide was used to produce the nanoparticles. The relative particle size relationship of the Au and Au-Pt nano particles (NP's) was investigated, relating the Pt concentration and the support polymorph over a temperature range. It was found, with the use of in-situ variable temperature powder X-ray diffraction (VT-PXRD) and transmission electron microscopy (TEM), that the addition of Pt to the Au system corresponded to a reduction in particle size over a broad temperature range.

A Simple Low Temperature and Pressure Method for the Synthesis of Quasi-One Dimensional Nano Structures of TiO2 for Dye Synthesized Solar Cells

2014 ◽  
Vol 28 ◽  
pp. 121-129 ◽  
Author(s):  
Masoud Karimipour ◽  
Mozhdeh Khancheh Zar ◽  
Mehdi Molaei
Keyword(s):  
Solar Cell ◽  
Anatase Phase ◽  
Xrd Analysis ◽  
Spherical Particles ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Nano Structures ◽  
Dispersing Agent ◽  
Shape Structure ◽  
Average Size

In this work we have synthesized TiO2nanostructures using a modified autoclave-free hydrothermal method from bulk powders. In the absence of pressure, Toluene was used as the dispersing agent to prohibit particle aggregation during the thermal treatment. Toluene to Ti mole ratio (X) was varied from 0 up to 30 to obtain different morphologies of TiO2. X-ray diffraction (XRD) analysis demonstrated the Anatase phase for all the samples. FTIR analysis indicated that samples are free of carbon rich compounds and carbon contaminants. SEM images showed that with the increase of Toluene to Ti ratio, the morphology of the powders change from spherical particles with an average size of about 45 nm for X=0 to broccoli-shape structure for X=10, nanotubes for X=20 and nanosticks/wires for X=30. The synthesized TiO2nanotubes have been used as photoanode in a dye synthesized solar cell (DSSCs). The efficiency of the fabricated solar cell without any further modification was obtained about 2.3%.

In-Situ TEM Observation on Phase Formation of TiO2 Nanoparticle Synthesized by Flame Method

2007 ◽  
Vol 534-536 ◽  
pp. 81-84 ◽  
Author(s):  
Hoon Park ◽  
H.S. Jie ◽  
Kyou Hyun Kim ◽  
Jae Pyong Ahn ◽  
Jong Ku Park
Keyword(s):  
Phase Transformation ◽  
Anatase Phase ◽  
Flame Temperature ◽  
Phase Evolution ◽  
Tio2 Nanoparticle ◽  
In Situ Tem ◽  
Titanium Tetraisopropoxide ◽  
Organic Precursor ◽  
Rutile Tio2 ◽  
Flame Method

TiO2 nanoparticle was synthesized by the flame method using a metal organic precursor of titanium tetraisopropoxide (TTIP, Ti(OC3H7)4), which was controlled by varying the ratio and flow rate of gas mixtures consisting of oxygen (oxidizer), methane (fuel) and nitrogen (carrier gas). The morphology and the size distribution of nanoparticles were observed with TEM and FESEM, and the phase evolution was analyzed by XRD measurement using a monochromator. The crystalline phases of TiO2 nanoparticle depended strongly on the temperature distribution in the flame, whereas the morphology was not sensitive. During the flame synthesis of TiO2 nanoparticle, anatase TiO2 nanoparticle was predominantly synthesized at the high flame temperature and rapid flame cooling condition. The low flame temperature and long flame length enabled to form almost rutile TiO2 nanoparticle (>95%). The anatase nanoparticle was formed by a homogeneous nucleation and has finally kept the anatase phase without the phase transformation any more in the flame. However, the rutile TiO2 nanoparticle was not formed directly and homogeneously in flame, and was manufactured by the phase transformation such as amorphousanataserutile. It was proved that the rutile phase was nucleated heterogeneously from the amorphous or anatase particles.

scholarly journals Modification of Energy Band Gap in Natural Dye-Sensitized Tio2 Nano Particles

2016 ◽  
Vol 1 (1) ◽  
Keyword(s):  
Solar Cells ◽  
Band Gap ◽  
Anatase Phase ◽  
Sol Gel ◽  
Dye Sensitized Solar Cells ◽  
Pure Tio2 ◽  
Natural Dye ◽  
Nano Particles ◽  
Attractive Alternative ◽  
Dye Sensitized

The photovoltaic devices have been fabricated using conventional semiconductor materials such as silicon (Si) which are quite expensive and difficult to manufacture. Dye-sensitized solar cells (DSSCs) are attractive alternative to Si-based solar cells as they can be inexpensive, portable, thermally stable, light in weight and flexible. The pure TiO2 nano particles have been prepared by sol gel method for DSSC in this project. The anatase phase of TiO2 has been confirmed using XRD. Transmission Electron Microscopy has been used to the nano particle size of the TiO2 nano particles. The coating of natural dyes extracted from spinach and marry gold has been done on TiO2 nano particles. The Scanning Electron Microscope and EDX study reveals the morphology and elemental composition of the pure and natural dye coated TiO2 nano particles. Tauc’s Plots confirmed decrease in band gap with the natural dye coating. The natural dye coated nano particles are found to be better candidates for DSSCs.

Study of Different TiO2 Electrode Structures on Dye-Sensitized Solar Cell

2008 ◽  
Vol 368-372 ◽  
pp. 1716-1719 ◽  
Author(s):  
Teen Hang Meen ◽  
Chien Jung Huang ◽  
Yin Wei Chen ◽  
Liang Wen Ji ◽  
Chien Chen Diao ◽  
...  
Keyword(s):  
Solar Cell ◽  
Tio2 Film ◽  
Anatase Phase ◽  
Sol Gel ◽  
Nano Particles ◽  
Dye Sensitized Solar Cell ◽  
Tio2 Electrode ◽  
Film Electrode ◽  
Visible Absorption ◽  
Dye Sensitized

In this research, applications of different TiO2 electrode structures on Dye-Sensitized Solar Cell were investigated. The different TiO2 electrode structures include: (1) synthesis of TiO2 nano-particles and TiO2 film electrode by sol-gel and spin-coating method; (2) fabrication of the TiO2 film electrode by RF Sputtering; (3) fabrication of the rod TiO2 electrode by photo lithography. X-ray diffraction patterns show that the best sintering temperature of nano-TiO2 thin film is 500oC, at which TiO2 anatase phase forms best and the smallest particle-size (8-10 nm) can be obtained. Ultraviolet-visible absorption spectra reveal that the rod TiO2 electrode with TCPP sensitizer adsorbed on has the best optical absorption from 400 nm to 700 nm. The results of current-voltage analyses reveal that the solar cell with rod TiO2 electrode has higher conversion efficiency than the others. This result also provides clear evidence for the contact area between TiO2 electrode and TCPP sensitizer plays an important role on the efficiency of dye-sensitized solar cell.

scholarly journals Systematic UHV-AFM experiments on Na nano-particles and nano-structures in NaCl

2005 ◽  
Vol 2 (1) ◽  
pp. 289-293 ◽  
Author(s):  
A. V. Sugonyako ◽  
A. A. Turkin ◽  
R. Gaynutdinov ◽  
D. I. Vainshtein ◽  
H. W. den Hartog ◽  
...  
Keyword(s):  
Nano Particles ◽  
Nano Structures

scholarly journals AFM of Metallic Nano-Particles and Nano-Structures in Heavily Irradiated NaCl

2003 ◽  
Vol 158 (1-6) ◽  
pp. 77-82 ◽  
Author(s):  
R. Gaynutdinov ◽  
D.I. Vainshtein ◽  
S.J. Hak ◽  
A. Tolstikhina ◽  
H.W. Den Hartog
Keyword(s):  
Nano Particles ◽  
Nano Structures

Photooxidation in Combination with Nanotechnologies - Principles, Developments and R&D Approaches of an Advanced Technology for Water and Air Treatment - Uviblox®

2011 ◽  
Vol 14 (2) ◽  
Author(s):  
Frank Seitz ◽  
Katrin Pollmann ◽  
Katrin Mackenzie ◽  
Siegfried Opiolka
Keyword(s):  
Nano Particles ◽  
Advanced Technology ◽  
Development Projects ◽  
Waste Gas ◽  
Air Treatment ◽  
Nano Structures ◽  
Inorganic Substances ◽  
Technical Systems ◽  
Uv Lamps ◽  
Water Waste

AbstractMany organic and oxidizable inorganic substances are main targets for oxidation and destruction during treatment, purification and disinfection of contaminated ground water, waste water, air, soil and waste gas and odor. Uviblox® technology uses the effects of photooxidation and photocatalytical processes by middle and low pressure UV lamps for technical systems. There are many possibilities for combination and optimisation of photooxidation with other technologies like nanotechnologies. Degradation processes can be enforced by nano structures of photocatalysts significantly. Different approaches are strongly pursued in research & development projects like NanoAqua, Fe-NANOSIT and nanoblox. These projects search for different ways of applying and handling the photocatalytical nano particles like TiO

Atom-Bridge to Nano-Wire

1997 ◽  
Vol 3 (S2) ◽  
pp. 391-392
Author(s):  
K. Takayanagi ◽  
Y. Kondo ◽  
H. Ohnishi ◽  
Q. Ru ◽  
H. Kimata
Keyword(s):  
Quantum Wires ◽  
Electron Tunneling ◽  
Point Contact ◽  
Chemical Properties ◽  
Nano Particles ◽  
Nano Particle ◽  
Nano Structures ◽  
Resolution Electron ◽  
Phase Interference ◽  
Physical And Chemical

Nano-fabrications are now available for us to produce well-defined nano-structures showing quantum effects, quantized electron conductance at point contact, of phase interference of electron waves at quantum wires, and single electron tunneling at nano-capacitors. It seems near that we can fabricate even such nano-structures that Professor L.Feynman had described in his book “miniaturization”: the smallest memory unit(nano-particle), which contains 5x5x5 atoms. Such nano-particles are expected to have physical and chemical properties depending on their surface nature, since they have rather large volume of surface atoms compared with that of the core atoms. The surface atoms of such nano-particles might be reconstructed to a structure different from their bulk crystal structure, as well the surfaces of silicon and GaAs are reconstructed. It is, therefore, interesting to fablicate such nano-particles and to study their structures.To study structure and properties of nano-particle surfaces, we developed a UHV high-resolution electron microscope equipped with a field-emission gun (UHV-FE-HR TEM: revised version of JEOL 2000V) at our ERATO project, as shown in fig. 1.

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