Effect of Cobalt additon of SnO2 by using hydrothermal method and its supercapacitor application
-
Upload
karthik506 -
Category
Documents
-
view
113 -
download
4
description
Transcript of Effect of Cobalt additon of SnO2 by using hydrothermal method and its supercapacitor application
CHONNAM NATIONAL UNIVERSITYCHONNAM NATIONAL UNIVERSITY
SnO2 and Cobalt doped SnO2 materials were prepared using low
temperature hydrothermal method.
XRD reveals that the substitution of Co affects the crystal
structure of SnO2 and increases the crystallization of the materials.
TEM images shows that SnO2 and Sn1-xCoxO2 particles are well
developed and have spherical morphology with an average size of
2-4 nm.
Cyclic voltammetry curves show rectangular-like shape which
reveals the capacitive behavior of the materials.
Maximum capacitance of 840 F/g is obtained from Sn0.6Co0.4 O2 in
1 M H2SO4 recorded at 10 mV/s scan rate.
ConclusionsConclusions Aim of the workAim of the work
IntroductionIntroduction
AdvantagesAdvantages
Virtually unlimited cycle life
Low impedance
Simple charge methods
Cost-effective energy storage
DisadvantagesDisadvantages
Unable to use the full energy
spectrum
Low energy density
Cells have low voltages
High self discharge
Supercapacitors (ECs) or ultracapacitors are being widely used for energy storage
in many applications, such as portable electronic devices, and electrical vehicles
etc.
The supercapacitor resembles a regular capacitor except that it offers very high
capacitance in a small package.
Classification of ECsClassification of ECs
Electrochemical double Electrochemical double layer capacitor (EDLC)layer capacitor (EDLC)
Stores energy by double layer, which is formed by the charge separation between the electrode/electrolyte interface
Electrode materials – high surface area carbon such as Activated carbon, Carbon aerogel, Carbon mat, etc.
Redox capacitors (RC)Redox capacitors (RC)
Stores energy by utilizing the pseudocapacitance, which is arising from the redox reactions of active materials
Metal oxides – NiO, MnO2, IrO2 and RuO2
Conducting polymers: PANI, Polythiophene etc.
Among all of the electrode materials, RuO2 exhibits a higher specific capacitance,
good electrical conductivity and stability. However, the high cost and scarce material
retarded its commercial acceptance
A cheap material with equivalent performance is required. Transition metal oxides
have been considered as promising materials for supercapacitors.
To replace RuO2 with cheap
transition metal oxide.
Cobalt doped tin oxide
simples have been synthesized
by hydrothermal method for
supercapacitor application.
Supercapacitive behavior of
Sn1-xCoxO2 samples were
evaluated by cyclic
voltammogram (CV) in 1 M
H2SO4 recorded at 10 mV/s
scan rate.
Stoichiometric amount of
SnCl2 and CoCl2 in 50 ml 0.1 M
NaOH solution and stirred
Add 10 ml ethylene glycol
followed by heating to dissolve
Transferred to teflon autoclave
and heated at 180 0C for 24h.
Sn1-xCoxO2 particles were
separated by centrifuge and
dried at 600 C for 12h
20 30 40 50 60 70 80
SnO2
2 theta (deg)
Sn0.8
Co0.2
O2
Sn0.6
Co0.4
O2
Sn0.4
Co0.6
O2
Sn0.2
Co0.8
O2
(11
2)(
30
1)
(21
1)
(20
0)
(10
1)
(11
0)
Inte
nsi
ty (
A.U
)
Results and discussionResults and discussion
1000 800 600 400
SnO2
% T
ran
smitt
an
ce
Wavenumbers (cm -1)
Sn0.8
Co0.2
O2
Sn0.6
Co0.4
O2
Sn0.4
Co0.6
O2
Sn0.2
Co0.8
O2
The intensity of the diffraction peaks increases with the
increase in the Co content, which indicates the
enhancement of the crystallization of the materials
The peaks observed at 650, 603, 561 are
typical for Sn-O stretching vibrations.
Similarly the peak at 483 cm-1 corresponds to
the Co-O-Co stretching mode, which is not
available for the bare SnO2.
(a) - SnO2
(b) - Sn0.8Co0.2O2
(c) - Sn0.6Co0.4O2
(d) - Sn0.4Co0.6O2
(e) - Sn0.2Co0.8O2
Effect of cobalt addition of SnOEffect of cobalt addition of SnO22 nanoparticles by using hydrothermal nanoparticles by using hydrothermal
method and its capacitor applicationsmethod and its capacitor applications
K. KarthikeyanK. Karthikeyan11, D. Kalpana, D. Kalpana22, S.B. Lee, S.B. Lee11, I.C. Jang, I.C. Jang11, H.H. Lim, H.H. Lim11, Y.S. Lee, Y.S. Lee11
11 Faculty of Applied Chemical Engineering, Chonnam National University, Gwangju 500-757, Republic of KoreaFaculty of Applied Chemical Engineering, Chonnam National University, Gwangju 500-757, Republic of Korea
22 Central Electrochemical Research Institute, Karaikudi 630 006, India Central Electrochemical Research Institute, Karaikudi 630 006, India
When the Co content
increased from 0.2 to 0.8 the
particle sizes decreased
from 2.59 nm to 2.36 nm.
The doping of Co in SnO2
has an influence on the
crystallite size and the
addition of Co decreases the
growth of the crystalline
grains of SnO2.
-0.8 -0.6 -0.4 -0.2 0.0
-18
-15
-12
-9
-6
-3
0
3
6
9
12
SnO2
Sn0.8
Co0.2
O2
Sn0.6
Co0.4
O2
Sn0.4
Co0.6
O2
Sn0.2
Co0.8
O2
Cur
rent
(A
g-1)
Potential (V)
The cyclic voltammogram of
pure and Co-doped SnO2 in 1
M H2SO4 recorded at 10 mV/s
scan rate.
From the CV, a maximum
capacitance of 840 F/g was
obtained for the Sn0.6Co0.4 O2.
XRD patternsXRD patterns
FTIR spectrum
TEM imagesTEM images
Cyclic Voltammetry studiesCyclic Voltammetry studies
PreparationPreparation