3. INTRODUCTION
• Ever since Somia Iijima discovered carbon nanotubes, carbon nanotube has
exciting properties
• carbon nanotubes use in microelectronic technology,
• similarly to organic nanotubes there is inorganic nanotubes (especially metal
sulfides or oxides)
• Among all transition-metal oxides, TiO2 is the most extensively studied material
• Titanium is the ninth most abundant element in the Earth’s crust.
• TiO2, is often used in many applications .
4. PHYSICAL
PROPERTIES
• Titanium(IV) oxide or titania.
• It’s the naturally occurring oxide of titanium
• Chemical formula ;-TiO2.
• It’s odorless , white powder, Tasteless , pH 7.5.
• It occurs in three crystalline forms ilmenite , rutile and anatase .
• It’s Boiling point 4532 to 5432 °F at 760 mm Hg
• It has Melting point of 3380 °F
• It has Density 3.9 to 4.2
• It has bandgap of 3.2 eV
5. SYNTHESIS:
There are three general approaches to the
synthesis of TiO2 namely:
1) Chemical (template) synthesis,
2) Electrochemical approaches (e.g.,
anodizing of Ti),
3) The alkaline hydrothermal method.
TiO2 can also be prepared by
a) Molecular beam epitaxy
b) Solgel method (chemical synthesis)
c) CVD or PVD
6. 1. It can be prepared by direct combination of titanium and oxygen; by treatment
of titanium salts in aqueous solution; by reaction of volatile,
inorganic titanium compounds with oxygen; by oxidation or hydrolysis of organic
compounds of titanium
2. By adding ammonia or an alkali carbonate to a solution of
titanyl sulfate (TiOSO4). Titanic acid Ti(OH)4 or TiO(OH)2 is precipitated and,
after filtration and washing, is dried and ignited.
3. In the chloride process, the titanium-containing raw materials ilmenite,
leucoxene, rutile, titanium slag, or anatase are chlorinated at 700 - 1200 °C. The
TiCl4 is oxidized at temperatures of 900 - 1400 °C to form TiO2.
7. 1. X-RAY DIFFRACTION (XRD)
2. SCANNING ELECTRON MICROSCOPE:
A). FIELD EMISSION SCANNING ELECTRON MICROSCOPE
B). HIGH RESOLUTION TRANSMISSION ELECTRON MICROSCOPE
3). UV-VISIBLE SPECTROSCOPY
4). ELECTRON DISPERSIVE X-RAY (EDX)
5). DYNAMIC LIGHT SCATTERING (SIZE)
CHARACTERISATION:
8. APPLICATION
• Applications of TiO2 nanostructures usually involve the exploitation of some
unique feature of TiO2 and a significant enhancement of some reaction or
transport rates that is obtained by using small scale dimensions.
• The main application are as follow :
1. Photocatalysis and Dark Photocatalysis
2. Solar cells
3. Drug Delivery and the Release of Other Payloads
4. Gas sensing (co2,h2,no gases)
5. Electrochromic Devices
also in cosmetics, sunscreen and dusting powder
9. PHOTOCATALYSIS
• A photocatalyst is a material which absorbs light to bring it to higher energy
level and provides such energy to a reacting substance to make a chemical
reaction occur.
• TiO2 anatase plays a central role in energy and environmental research. A
major bottleneck toward developing artificial photosynthesis with TiO2 is that
it only absorbs ultraviolet light, owing to its large bandgap of 3.2 eV.
• The photocatalytic degradation of Reactive Blue 4 (RB4), an anthraquinone
dye, has been investigated using pure anatase nano titanium (IV) oxide (TiO2).
10. PHOTOCATALYSIS
• A photocatalyst is a material which absorbs light to bring it to higher energy
level and provides such energy to a reacting substance to make a chemical
reaction occur.
• TiO2 anatase plays a central role in energy and environmental research. A
major bottleneck toward developing artificial photosynthesis with TiO2 is that
it only absorbs ultraviolet light, owing to its large bandgap of 3.2 eV.
• The photocatalytic degradation of Reactive Blue 4 (RB4), an anthraquinone
dye, has been investigated using pure anatase nano titanium (IV) oxide (TiO2).
11. Procedure:
• The coating of anatase TiO2 on the substrate surface (transparent plastic)
by using spray method.
• The coating process begins by mixing the anatase TiO2 powder and DI
Water with the ratio of 5 gr : 50 mL respectively using magnetic stirrer for
30 minutes.
• The next step is washing the transparent mica plastic using 95% alcohol.
The solution is placed in the spray equipment. In this step, parameters are
optimized to obtain samples with more TiO2 surfaces that can be in direct
contact with the pollutant.
• The optimized parameters are the use of additional adhesive polymers
(Araldite, Alteco, G glue) and spray frequency (5-20 times). Additional
adhesive polymers superimposed on plastic substrates by doctor blade
method.
12. • Along with removal of organic waste, the fabric-supported Pd/TiO2 shows
higher inhibition activity for algal growth.
• The ability of the TiO2-coated materials to inhibit algae correlated well with
their activity for the photocatalytic decolorization of methylene blue,
suggesting a nonspecific mechanism in the breakdown of cellular structures.
15. PHOTOCATALYTIC TIO2 FILMS AND MEMBRANES FOR THE
DEVELOPMENT OF EFFICIENT WASTEWATER TREATMENT AND REUSE
SYSTEM:
PUBLISHED IN “DESALINATION” VOLUME 202, ISSUES 1–3, 5 JANUARY 2007, PAGES 199-206
Hyeok Choi, Elias Stathatos, Dionysios DDionysiou
• TiO2/Al2O3 composite membranes with simultaneous photocatalytic, disinfection,
separation, and anti-biofouling properties. The highly porous TiO2 material exhibited high
specific surface area and porosity, narrow pore size distribution, homogeneity without
cracks and pinholes, active anatase crystal phase, and small crystallite size.
• These TiO2 materials were highly efficient in the decomposition of methylene blue dye
and creatinine, destruction of biological toxins (microcystin-LR), and inactivation of
pathogenic microorganisms (Escherichia coli). Moreover, the photocatalytic TiO2
membranes exhibited not only high water permeability and sharp polyethylene glycol
retention but also less adsorption fouling tendency. Here, we report results on the
synthesis, characterization, and environmental application and implication of
photocatalytic TiO2 films and membranes.
16. ENHANCED PHOTOCATALYTIC AND ANTIBACTERIAL ACTIVITIES OF
MECHANOSYNTHESIZED TIO2–AG NANOCOMPOSITE IN WASTEWATER
TREATMENT:
PUBLISHED IN “JOURNAL OF MOLECULAR STRUCTURE” VOLUME 1211, 5JULY
Moupiya Ghosh, Moumita Mondal, Samir Mandal, Anindita Roy, Subhendu Chakrabarty, Gopal
Chakrabarti, Swapan Kumar Pradhan:
• TiO2–Ag nanocomposite (NC) has been successfully synthesized by mechanical alloying (MA)
the TiO2 and Ag powder mixture for the 3h under Ar atmosphere.
• The Rietveld refinement of XRD data and FTIR spectra analyses reveal the detailed structural
and microstructural parameters of this nanocomposite. Particle size and elemental
composition of the nanocomposite are measured from FESEM,TEM images and EDS
spectrum respectively.
• A notable photocatalytic activity (∼95% degradation of Rhodamine B (RhB), ∼76% of
Methylene Blue (MB), ∼23% of Methyl Orange (MO)) of this NC is revealed under visible
light irradiation within 330 min. A significant antibacterial activity of the NC against E.coli
and Staphylococcus aureus bacteria is revealed using the disk agar diffusion method. In
comparison to pure TiO2, both photocatalytic and antibacterial activities of the NC are
found to enhance significantly.
• This synthesized NC by a fast and facile MA method within a short duration of 3h has a
great potential in removing organic pollutants and bacteria from industrial wastewater so
that the purified wastewater can be reused in textile and other chemical industries.
17. NEW PHOTOACTIVE MESOPOROUS CE-MODIFIED TIO2 FOR SIMULTANEOUS
WASTEWATER TREATMENT AND ELECTRIC POWER GENERATION
PUBLISHED IN 13 OCTOBER 2020 IN JOURNAL CATALYSIS TODAY
Mihaela Mureseanu, Valentina Chivu, Mariana Osiac, Madalina Ciobanu, Cristina Bucur, Viorica Parvulescu, Nicoleta
Cioatera,
In the present paper is presented an efficient strategy for synthesis of mesoporous TiO2
modified with different Ce concentrations through a sol–gel process in the presence of triblock
Pluronic P123 as structure directing agent, integrated with evaporation-induced self- assembly
(EISA) approach. The nanocomposite consisted mostly of small crystallite of anatase. The
presence of a new crystal phase corresponding to cerium titanate was evidenced in Ce-
modified powder samples. All materials were characterized by SEM and TEM microscopies,
UV–vis, XPS and N2 adsorption-desorption isotherms in order to examine the textural and
structural characteristics and the chemical nature of their surface. Furthermore, the
photoelectrochemical characterization evidenced the effect of the TiO2 mesoporous structure,
the amount of cerium and the oxidation state of Ti and Ce in the new photocatalysts on the
enhanced photovoltaic performance. The photocatalytic activity of the as-synthesized
materials was evaluated for phenol photodegradation in aqueous media and the reactive
species involved in photocatalytic process were established by using some radical scavengers
in the photodegradation experiments. Based on the obtained results, these new Ce-modified
mesoporous TiO2 photocatalysts could be considered for degradation of organic compounds
from wastewaters by advanced oxidation processes or for photoanodes construction for
efficient photoelectrochemical fuel cell (PFC) systems.