ARTICLE
Copyright © 2014 by American Scientific Publishers
All rights reserved.
Printed in the United States of America
Journal of Nanoengineering and Nanomanufacturing
Vol. 4, pp. 1–6, 2014
(www.aspbs.com/jnan)
Synthesis of Nanostructured Ta
2
O
5
and Its
Photocatalytic Performance Study
Siddharth P. Deshpande
1
, Mohaseen S. Tamboli
2
, Sudhir S. Arbuj
2, *
,
Uttam P. Mulik
2
, and Dinesh P. Amalnerkar
2
1
Department of Metallurgy, College of Engineering, Shivajinagar, Pune-411005, India
2
Centre for Materials for Electronics Technology, Panchwati, Pune-411008, India
ABSTRACT
Nanostructured Tantalum pentoxide (Ta
2
O
5
) was prepared using solvothermal reaction technique at 200
C for
24 hrs. The prepared Ta
2
O
5
was characterized using X-ray diffractometry, diffuse reflectance UV-visible and
photoluminescence spectroscopy, FE-SEM and TEM techniques. The broad diffraction peaks in XRD confirm
the formation of nano structured Ta
2
O
5
. FE-SEM and TEM analysis showed presence of nanostructured parti-
cles having size in the range of 5 to 10 nm. Photocatalytic activity was evaluated by observing the degradation
of aqueous rhodamine 6G (R6G) and methylene blue (MB) dye under 400 W mercury vapor lamp. Ta
2
O
5
calcined at 400
C showed apparent rate constant values of 0.017 and 0.016 min
-1
for MB and R6G dye
respectively. The study indicates the possible use of Ta
2
O
5
as a photocatalyst for solar energy utilization as
well as for environmental remediation.
KEYWORDS: Nanomaterials, Tantalum Pentoxide, Solvothermal, Photocatalysis, Dye Degradation.
1. INTRODUCTION
Heterogeneous photocatalysis has gained more attention
for solving environmental and energy related issues.
1 2
This photocatalysis technique has been effectively uti-
lized for large number of applications like destruction of
bacteria, viruses and molds, odour control, environmen-
tal remediation, volatile organic compound (VOCs) degra-
dation and even as a glass self cleaner by introducing
superhydrophilicity.
3–8
The efficacy of any heterogeneous
photocatalytic process relies mainly on the availability
of suitable photocatalyst having proper conduction and
valence band levels. In order to enhance the photocat-
alytic efficiency, researchers have tried many catalysts but
still finding newer photocatalyst with higher activity is a
challenge in front of scientific community. Till today vari-
ous semiconductor oxides/sulfides have been exploited viz.
TiO
2
, ZnO, SnO
2
, CdS, ZnS, SnS
2
, WO
3
, and Fe
2
O
3
as
photocatalyst for energy as well as environment related
applications.
9–19
Furthermore, the change in synthesis
methods showed change in the photocatalytic activity as
function of surface area and crystallanity. Additionally, the
photocatalytic activity can be improved by doping cation
as well as anions by lowering the band gap of catalyst
leading visible light absorption.
20
Coupled semiconductor
∗
Author to whom correspondence should be addressed.
Email: sudhir1305@gmail.com
Received: xx Xxxx Xxxx
Accepted: xx Xxxx Xxxx
systems of oxide/oxide as well as sulphide/oxide type also
reported to have enhanced photoactivity.
21–23
The coupled
catalysts effectively separate the electron–hole generated
upon illumination with proper wavelength of light. Using
carbon nanotubes and graphene in combination with TiO
2
and ZnO showed higher photoactivity as compared to their
individual activity.
24 25
Among the studied catalysts, metal
oxides as compared to metal sulfides are the most stable
wide band gap materials with good photocatalytic activity.
Metal sulphides require hole scavengers otherwise it get
corrode resulting poor activity.
26
Of late, tantalum pentoxide (Ta
2
O
5
) has received enor-
mous attention as a heterogeneous photocatalyst for pol-
lution abatement and water splitting into H
2
and O
2
.
27
As
Ta
2
O
5
have superior thermal, chemical and biological sta-
bility, wide band gap (3.8 eV), high dielectric constant
and refractive index. Due to these properties Ta
2
O
5
has
various applications in capacitors, high temperature reflec-
tors, dynamic random access memories, optical coatings,
gas sensors and so on.
28–30
Recently, Liang and co-workers
reported the liquid phase laser ablation synthesis of core
shell structured Ta
2
O
5
nanoparticles and investigated its
photocatalytic activity using methylene blue degradation.
31
Maggard et al. reported the solid state and flux mediated
synthesis of tantalate based materials and studied photocat-
alytic measurements of H
2
and O
2
production in aqueous
solutions.
32
Wachs et al. studied the fundamental structure-
photoactivity relationships for the highly active tantalum
based photocatalysts.
33
So far many reports have proven
J. Nanoeng. Nanomanuf. 2014, Vol. 4, No. xx 2157-9326/2014/4/001/006 doi:10.1166/jnan.2014.1196 1
J. Nanoeng. Nanomanuf., 2014, 4, 215-220