Synthetic
Metals
161 (2011) 2045–
2048
Contents
lists
available
at
ScienceDirect
Synthetic
Metals
journa
l
h
o
me
page:
www.elsevier.com/locate/synmet
Short
communication
Study
on
poly-O-anisidine
film
with
the
properties
of
electrochromism
and
infrared
emissivity
modulation
Liangliang
Tu, Chunyang
Jia
∗
,
Xiaolong
Weng,
Longjiang
Deng
State
key
Laboratory
of
Electronic
Thin
Films
and
Integrated
Devices,
School
of
Microelectronics
and
Solid-State
Electronics,
University
of
Electronic
Science
and
Technology
of
China,
Chengdu
610054,
China
a
r
t
i
c
l
e
i
n
f
o
Article
history:
Received
15
January
2011
Received
in
revised
form
2
June
2011
Accepted
20
June
2011
Available online 20 July 2011
Keywords:
Poly-O-anisidine
Electropolymerization
Cyclic
voltammetry
Electrochromic
film
Emissivity
a
b
s
t
r
a
c
t
The
poly-O-anisidine
(POA)
electrochromic
film
was
obtained
by
cyclic
voltammetry
method.
The
optical
properties
of
the
electrochromic
film
were
investigated
by
UV–vis
spectrophotometer
and
FT-IR
spec-
troscopy.
The
results
show
that
the
different
colors
of
the
electrochromic
film
can
be
achieved,
which
exhibit
as
light
yellow-green,
light
dark
green
and
blue.
The
maximum
difference
of
the
UV–vis
absorption
of
the
film
is
about
40%
between
−0.5
V
and
0.9
V
and
the
biggest
different
average
emissivity
dynamic
of
the
film
is
0.553
in
the
wavelength
of
8–14
m
regions.
© 2011 Elsevier B.V. All rights reserved.
1.
Introduction
Electrochromism
(EC)
can
be
defined
as
a
reversible
and
visi-
ble
change
in
the
transmittance
and/or
reflectance
of
a
material
by
applying
different
voltages
or
electric
currents
with
the
result
of
electrochemical
oxidation
or
reduction
[1,2].
Recently,
elec-
trochromic
devices
are
now
being
studied
for
modulation
of
radiation
in
the
near
infrared,
thermal
infrared
and
microwave
regions
[3,4].
There
are
several
categories
of
EC
materials
that
are
capable
of
modulating
light
in
the
mid-IR
region.
Besides
metal
oxides,
conducting
polymers
as
promising
electrochromic
mate-
rials
due
to
their
lots
of
special
virtues,
which
including
multicolor
capability,
high
contrast
ratios,
fast
response
time,
narrow
potential
windows
of
application
with
the
perspective
for
long-term
optical
stability,
and
their
optical
properties
can
be
tailored
by
anodic
or
cathodic
coloring
[5–8].
Many
valuable
works
have
been
explored
in
the
field
of
EC
materials
based
on
conducting
polymer.
Li
et
al.
[9]
studied
the
IR
electrochromism
of
a
polyaniline
(PANI)
system
with
sul-
furic
acid
as
dopant
and
the
optical
properties
of
the
devices
were
characterized
by
spectrophotometry
in
the
wavelength
range
from
0.4
m
to
15
m.
The
results
show
that
the
devices
have
an
average
reflectance
dynamic
range
as
34%
and
an
aver-
age
emissivity
dynamic
range
of
ca.
0.24
in
8–12
m
region.
∗
Corresponding
author.
Tel.:
+86
28
83202550;
fax:
+86
28
83202569.
E-mail
address:
cyjia@uestc.edu.cn
(C.
Jia).
Chandrasekhar
et
al.
[10]
reported
the
IR
electrochromic
film
syn-
thesized
by
potentiostatical
electropolymerization
at
+1.2
V
(vs.
Pt
quasi-reference),
copolymerization
with
aniline
and
diphenyl
amine
(in
96%/4%
molar
proportion)
using
polymeric
materials
as
dopant
and
the
emissivity
of
the
device
varied
from
0.32
to
0.79.
To
the
best
of
our
knowledge,
there
is
few
research
con-
cerning
the
aniline
derivatives
as
the
variable
emissivity
material.
The
methoxyl
group,
as
auxiliary
electro-donating
substituent
in
the
polymer
may
exhibit
more
favorable
for
processing
the
corresponding
film
[11],
modulating
the
film’s
conductivity
and
electrochromic
efficiency
as
well
as
enhancing
its
thermal
stability
[12,13].
In
this
paper,
an
electrochromic
film
based
on
POA
with
variable
emissivity
properties
was
synthesized
by
cyclic
voltammetry
and
performs
reversible
color
changes
in
the
electrochemical
doped
and
undoped
states.
The
optical
properties
of
the
film
were
character-
ized
by
UV–vis
spectrophotometer
and
FT-IR
spectroscopy.
2.
Experimental
2.1.
Materials
O-Anisidine,
ITO
glasses,
sulfuric
acid
and
sodium
dodecylben-
zenesulphonate
are
purchased
from
commercial
sources
and
used
without
any
purifications.
ITO
glass
(15
/)
is
purchased
and
cut
into
small
pieces
with
the
size
of
2
cm
× 4
cm,
which
are
washed
with
deionized
water
and
ethanol
several
times
0379-6779/$
–
see
front
matter ©
2011 Elsevier B.V. All rights reserved.
doi:10.1016/j.synthmet.2011.06.032