Vol.:(0123456789) 1 3
Journal of the Iranian Chemical Society
https://doi.org/10.1007/s13738-020-01993-0
ORIGINAL PAPER
Studies of the photocatalytic and electrochemical performance
of the Fe
2
O
3
/TiO
2
heteronanostructure
Abdelhak Othmani
2
· Salah Kouass
1
· Thamer Khalf
3
· Sabrine Bourchada
4
· Fathi Touati
3
· Hassouna Dhaouadi
3
Received: 25 March 2020 / Accepted: 29 June 2020
© Iranian Chemical Society 2020
Abstract
The α-Fe
2
O
3
/TiO
2
nanostructure material, synthesized on FTO (fuorine-doped tin oxide) substrate using the hydrothermal
method at 180 °C for 5 h, exhibits an enhanced performance in the photocatalytic degradation of an organic dye. The optical
band gap was found to decrease compared to the TiO
2
one. The photocatalytic performances of the as-prepared heterojunc-
tion were evaluated with the degradation of methylene blue (MB) in an aqueous medium. The results revealed that the pho-
tocatalytic activity of the Fe
2
O
3
/TiO
2
/FTO was much higher than that of the pure TiO
2
. In addition, the photocurrent of the
Fe
2
O
3
/TiO
2
/FTO heterojunction was remarkably higher than that of the bare TiO
2
electrode. The obtained results indicate that
the heterojunction formed between Fe
2
O
3
and TiO
2
signifcantly improved the separation efciency of the photo-generated
electron–hole pairs. The electrochemical properties of the as-synthesized nanocomposite materials (α-Fe
2
O
3
/TiO
2
) were also
evaluated with cyclic voltammetry for 1000 cycles. This nanocomposite exhibited an enhanced specifc discharge capacity
compared to the Fe
2
O
3
nanomaterial. The as-produced material proved to have an impressive performance as a high-capacity
anode for Na
+
-ion batteries.
Keywords Nanocomposite · Heterojunction · Photocatalytic properties · Electrochemical properties
Introduction
Green energy sources have been extensively investigated
in an attempt to replace fossil fuels, which have inherent
pollution problems, and given the limited availability of
resources [1]. In particular, the photocatalytic conversion
of solar energy into chemical energy or into hydrocarbon
fuels has been of great signifcance in environmental con-
servation and energy utilization [2, 3]. Over the last few
decades, much attention has been paid to the production
of various photocatalysts such as: TiO
2
[4], Au/ZnO [5],
C
3
N
3
S
3
[6] and MoS
2
[7]. Titanium dioxide (TiO
2
) is one of
the most commonly used photocatalysts given its efciency
in pollutant degradation in waste water, and also because
of its inexpensiveness, strong oxidizing power, hard-soluble
and long-term photostability [4]. However, its wide band
gap requires excitation with ultraviolet (UV) light, which
is only equivalent to 5–10% of the sunlight reaching the
surface of the earth. This limits its development and prac-
tical applications. Hence, enhancing photoactivity perfor-
mance under UV or visible light irradiation is necessary.
Several approaches, including metal and non-metal ion
doping and sensitization with organic and inorganic dyes,
have been developed to tune the band structure and broaden
the light response toward the long wavelength region [8].
TiO
2
coupled with other semiconductor transition metal
oxides to form heterojunction materials is another way of
extending the optical response range of TiO
2
and improv-
ing the quantum efciency. This system can be expected to
achieve high photocatalytic activity. Among these oxides,
Fe
2
O
3
presents a gap at around 2.0 eV [9, 10]. Fe
2
O
3
seems
to be compatible with TiO
2
and possesses a high solar-light
harvesting capability that is larger than that of TiO
2
. Indeed,
* Salah Kouass
koissa2000@yahoo.fr
1
Laboratoire des Matériaux Utiles, INRAP Sidi-Thabet,
2020 Tunis, Tunisia
2
Faculté des Sciences de Bizerte, LR01 ES15, Laboratoire
de Physique des Matériaux: Structure et Propriétés,
Université de Carthage, Faculté des Sciences de Bizerte,
7021 Zarzouna, Bizerte, Tunisia
3
Laboratoire Matériaux, Traitement et Analyses, INRAP,
Technopole Sidi-Thabet, Ariana Tunis, Tunisia
4
Laboratoire de Chimie des Matériaux, Faculté des Sciences
de Bizerte, 7021 Zarzouna, Bizerte, Tunisia