Volume 7 • Issue 3 • 1000257
J Phys Chem Biophys, an open access journal
ISSN: 2161-0398
Open Access
Research Article
Journal of Physical Chemistry &
Biophysics
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ISSN: 2161-0398
Sahbeni et al., J Phys Chem Biophys 2017, 7:3
DOI: 10.4172/2161-0398.1000257
*Corresponding author: Sahbeni K, National Hellenic Research Foundation,
Theoretical and Physical Chemistry Institute, 48, Vasileos Constantinou Ave.,
11635 Athens, Greece, Tel: +21698713283; E-mail: sahbani_kaouther@hotmail.fr
Received September 28, 2017; Accepted October 08, 2017; Published October
14, 2017
Citation: Sahbeni K, Sta I, Jlassi M, Kandyla M, Hajji M, et al. (2017) Annealing
Temperature Effect on the Physical Properties of Titanium Oxide Thin Films
Prepared by the Sol-Gel Method. J Phys Chem Biophys 7: 257. doi: 10.4172/2161-
0398.1000257
Copyright: © 2017 Sahbeni K, et al. This is an open-access article distributed
under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the
original author and source are credited.
Abstract
In this work, the low-cost sol–gel, spin-coating technique was used to grow TiO2 thin flms on silicon substrates.
The infuence of annealing temperature on the structural, morphological, and optical properties of TiO2 flms is
investigated. The structural properties of the TiO2 flms are investigated by Raman and Fourier transform infrared
(FTIR) Spectroscopy. Morphological properties are studied by Atomic Force Microscopy (AFM). The optical properties
are examined by photoluminescence (PL) and ultraviolet-visible (UV-vis) spectroscopy.
Annealing Temperature Effect on the Physical Properties of Titanium
Oxide Thin Films Prepared by the Sol-Gel Method
Sahbeni K
1,2,6
*, Sta I
2,3
, Jlassi M
3,4
, Kandyla M
6
, Hajji M
3,5
, Kompitsas M
6
and Dimassi W
1
1
Laboratoire Photovoltaïque, Centre de Recherche et des Technologies de l’Energie, Technopole de Borj-Cedria, BP 95, 2050, Hammam-Lif, Tunisia
2
Faculté des sciences de Bizerte, 7021 Jarzouna, Tunisia
3
Laboratoire de Semi-conducteur, Nano-structure et Technologie Avancée, Centre de Recherche et des Technologies de l’Energie, Technopole de Borj-Cedria, BP 95,
2050, Hammam-Lif, Tunisia
4
Ecole Supérieure des Sciences et Technologies du Design. Université de la Manouba, P5, Den Den, Tunisia
5
Ecole Nationale d’Electronique des Communication de Sfax, Technopôle de Sfax, Route de Tunis Km 10, Cité El Ons, BP 1163, 3021, Sfax, Tunisia
6
National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48, Vasileos Constantinou Ave., 11635 Athens, Greece
Keywords: Tin flms; Titanium oxide; Sol-gel; Annealing
temperature; Physical properties
Introduction
Titanium fnds more and more applications today. Over 96% of the
world-wide use of titanium is in its oxide form, TiO
2
(titanium dioxide),
thus creating a high demand for this material, due to a wide range of
potential applications for environmental purposes [1]. It is extensively
used for photo degradation of organic and inorganic pollutants [2],
photovoltaic energy production [3], hydrogen production by water
photo-splitting [4,5], and gas sensing [6,7]. Tis variety of applications
is because of TiO
2
low cost, non-toxicity, as well as useful optical,
physical, chemical, and electronic properties, including excellent
transmittance of visible light, photo catalytic behavior, high dielectric
constant, high refractive index, and high chemical stability [8,9].
It is well known that TiO
2
is an n-type semiconductor with an
indirect energy band gap [6,10,11]. It generally crystallizes in three
phases, the tetrahedral anatase (space group I4
1
/amd, density=3.894
g/cm
2
), rutile (space group P4
2
/mnm, density=4.25 g/cm
2
) and
orthorhombic brookite (space group Pcab, density=4.12 g/cm
2
). Te
anatase and rutile phases belong to diferent space groups but both
have a tetragonal crystal lattice. Rutile is the most stable form of TiO
2
,
whereas anatase and brookite are metastable and transform to the rutile
phase upon heating [6,12-14]. Conventional methods to prepare TiO
2
thin flms are pulsed laser deposition (PLD) [15,16], RF magnetron
sputtering [17-19] plasma enhanced chemical vapor deposition [20],
and sol-gel methods [6,15,21,22], among others. Focusing on the sol-
gel method, it is one of the most attractive techniques for thin-flm
deposition, because of low cost, non-vacuum requirements, large area
deposition, and low temperature processing. Furthermore, the sol-gel
method produces thin flms which have good homogeneity, excellent
compositional control, and good electrical and optical properties [23].
Te efect of the annealing temperature on TiO
2
powders has been
ofen reported in the literature [11-13]. Mathpal et al. have studied the
efect of annealing temperature on the structural and luminescence
properties of TiO
2
powders [12]. Another study has investigated the
efect of the annealing temperature on TiO
2
thin flms, prepared by the
sol-gel method and dip-coating techniques [22]. Tese studies have
that the annealing temperature infuences the structural and optical
properties of TiO
2
thin flms. Fewer articles investigate the phase
transition (from anatase to rutile) of TiO
2
thin flms obtained by the
sol-gel and spin coating techniques with annealing temperature, as
most articles study the properties of these flms at lower temperatures
[6].
Hence, we performed this work to understand the physical
properties of TiO
2
sol-gel more systemically and deeply. Te TiO
2
thin
flms are prepared by the sol-gel spin coating method and annealed
between 40 and 900°C. Te variation of structural properties of the
thin flm was studied through Raman, FTIR, PL spectroscopy and AFM
microscopy. Te crystalline structure, surface morphology and optical
properties of the TiO
2
thin flm were then studied and discussed. All
results indicate the dependence of the formed phases (anatase, rutile,
or mixed anatase-rutile phase) of TiO
2
thin flms on the annealing
temperature and indicate a phase transition which starts at 600°C.
Tis simple and no toxic method provided us results similar to those
given by other method more difcult and requires hard realization
conditions, in one hand. In other hand, we have shown that TiO
2
thin flms deposed in silicon substrates is a good agent to produce
antirefecting coating for solar cells.
Experimental
Te precursor solutions of TiO
2
, prepared by the sol-gel method,
were obtained using titanium (IV) isopropoxide (C
12
H
28
O
4
Ti) as the
starting material. Te titanium (IV) isopropoxide was initially added
in a mixture of ethanol and monoethanolamine (MEA) and the