Research Paper
Large scale flexible solid state symmetric supercapacitor through
inexpensive solution processed V
2
O
5
complex surface architecture
Bidhan Pandit
a
, Deepak P. Dubal
b,c
, Babasaheb R. Sankapal
a,
*
a
Nano Materials and Device Laboratory, Department of Physics, Visvesvaraya National Institute of Technology, South Ambazari Road, Nagpur-440010,
Maharashtra, India
b
Catalan Institute of Nanoscience and Nanotechnology, CIN2, ICN2 (CSIC-ICN), Campus UAB, E-08193 Bellaterra (Barcelona), Spain
c
School of Chemical Engineering, The University of Adelaide, Adelaide, South Australia 5005, Australia
A R T I C L E I N F O
Article history:
Received 12 August 2016
Received in revised form 19 March 2017
Accepted 2 May 2017
Available online 3 May 2017
Keywords:
Chemical method
V
2
O
5
flakes
supercapacitor
symmetric device
A B S T R A C T
Complex nanostructured morphology of V
2
O
5
has been grown on pliable stainless steel substrate (SS)
through simple and inexpensive chemical bath deposition (CBD) for all-solid state flexible supercapacitor
(SC). The structure and morphology of the synthesized V
2
O
5
thin films revealed the formation of
intermixed flakes. High specific capacitance of 735 F g
1
(at scan rate of 1 mV s
1
) of V
2
O
5
through liquid
configuration motivated us to form complete flexible all-solid state symmetric supercapacitor (FASC)
device. Remarkable specific capacitance of 358 F g
1
.
With 1.8 V wide potential window and high value of
capacitive retention of 88% over 1000 cycles has been achieved for FASC. Furthermore, the origin of
capacitive behavior from dual contributions of surface-controlled and diffusion-controlled charge
components has been evaluated to identify the dominating nature in electrochemical reactions. As
practical applicability, pliability of electrode has been tested at 175
bending angle along with the
integration to large scale electrode dimension (11 4 cm
2
).
© 2017 Elsevier Ltd. All rights reserved.
1. Introduction
Modern technology needs advanced energy storage devices for
wide range of applications. Hence, there is prevailing need to
design energy storage devices with flexible, light weight, high
efficiency, compact and with higher stability approach [1]. In order
to commercialize, the active electrode material should be easily
processed with low-cost technology along with integration
towards large scale production with optimum specific energy
(SE) and specific power (SP). Transition metal oxides are most
widely used as electrode material since they fulfill the above
criteria [2]. Due to diverse oxidation states and great electrical
conductivity, ruthenium oxide (RuO
2
) paid great attention in last
decades but limits the practical application in supercapacitor due
to its less abundance, higher cost and most importantly the toxic
nature [3]. Furthermore, much efforts have been focused for the
search of new active material such as MnO
2
[4], CuO [5], etc. for
supercapacitor application.
Recently, vanadium oxide and their distinct structures have
been perceived various front-line applications in catalysts [6],
lithium-ion batteries [7], sensors [8], solar cell window materials,
various electrochemical devices [9] and supercapacitors [10–12]
due to their different oxidation states, easy availability in
environment and low cost. Differences in electrochemical proper-
ties have been observed in V
2
O
5
thin films synthesized through
variety of techniques such as vacuum evaporation [13], sputter
deposition [14–17], pulsed laser deposition [18], chemical vapor
deposition [19–21], thermal oxidation [22,23], and sol–gel
processes [24] which are attributed to the synthesis routes, film
thickness, composition, surface morphology, and nanostructure.
Even Giorgetti et al. [25] synthesized dehydrated V
2
O
5
xerogel
contained thin film with amorphous nature. Now in term of
electrochemistry analyzed results, Wee et al. [26] prepared V
2
O
5
nanofibers for supercapacitor electrode with specific capacitance
of 190 F g
1
through electrospinning method. Reddy et al. [27]
synthesized nanoporous layered structure V
2
O
5
using sol-gel
method and developed specific capacitance of 214 F g
1
in 2 M KCl
electrolyte. But these values are still inferior to the RuO
2
. To
improve electrochemical characteristics, many exertions are given
to synthesize V
2
O
5
with altered morphology through different
techniques. In this context, Giorgetti et al. [28] reported that metal
* Corresponding author. Tel: +91 (712) 2801170; Fax: No: +91 712 2223230.
E-mail addresses: brsankapal@phy.vnit.ac.in, brsankapal@gmail.com
(B.R. Sankapal).
http://dx.doi.org/10.1016/j.electacta.2017.05.010
0013-4686/© 2017 Elsevier Ltd. All rights reserved.
Electrochimica Acta 242 (2017) 382–389
Contents lists available at ScienceDirect
Electrochimica Acta
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