Structural and energy storage
studies of Copper Oxide
Mei Shiyuan1, M .V. Reddy2, 3*, S. Adams3,
B.V.R.Chowdan2
1SRP
student, Hwa Chong Institution, 661, Bukit Timah
Road, Singapore 269734
2Department
of Physics, Solid State Ionics/Advanced
Batteries Lab, National University of Singapore,
Singapore 117542
3 Department of materials Science & Engineering;
National University of Singapore, Singapore 117546
*Corresponding Author:
phymvvr@nus.edu.sg;msemvvr@nus.edu.sg
Introduction
Lithium Ion Battery
 Power sources for portable devices
 Advantages:
 high energy density
 Lightweight
 a long life span
 Commercially used anode - graphite
 Low capacity of 372 mAh per gram,
compared with other materials (CuO 650mAh per gram)
2
Introduction
Copper Oxide
 High theoretical capacity
 More eco-friendly
In this project we prepared the
samples at various temperatures
and studied the effect of
reheating them to 750 oC
CuO has a Monoclinic structure
3
Preparation
Molten salt method
4
Preparation conditions
Sample Number
Materials used to prepare
the samples
Temperature
heated for the
first 3 hours (oC)
Temperature
reheated to(oC)
Sample 1
CuSO4·5H2O and
0.88M LiNO3:0.12M LiCl
280
750
Sample 2
Cu (NO3)2·3H2O and
0.88M LiNO3:0.12M LiCl
510
750
Sample 3
CuSO4·5H2O and
0.88M LiNO3:0.12M LiCl
650
750
Sample 4
CuSO4·5H2O and
0.88M LiNO3:0.12M LiCl
510
750
Sample 5
CuSO4·5H2O and
0.88M LiNO3:0.12M LiCl
410
750
Sample 6
Cu (NO3)2·3H2O and
0.88M LiNO3:0.12M LiCl
750
750
5
Fabrication of cells
 Super P Carbon – improved its conductivity
 Polyvinylidene fluoride (PVDF) - binder
 N-methyl pyrrolidone (NMP) – viscous slurry
6
Fabrication of cells
Top cap
Lithium
Separator
Electrolyte
Anode (CuO)
Bottom cap
7
Results and discussions
8
X-Ray Diffraction
- To study the crystal structure
70,000
60,000
50,000
40,000
30,000
20,000
10,000
0
-10,000
Tenorite
10
20
30
40
50
2Th eta(Degrees)
60
70
100.00 %
80
Tenorite
80,000
100.00 %
60,000
40,000
20,000
0
-20,000
10
20
30
40
50
2Th eta(Degrees)
60
70
80
Intensity (counts)
100,000
Tenorite
100.00 %
80,000
60,000
40,000
20,000
0
-20,000
-40,000
Intensity (counts)
10
20
30
40
50
2Th eta(Degrees)
60
70
80
70,000
60,000
50,000
40,000
30,000
20,000
10,000
0
-10,000
10
Tenorite 100.00 %
20
30
40
50
2Th eta(Degrees)
60
70
80
X-ray diffraction test
Compound
name
Lattice Parameters
Particle size (nm)
Crystal density
(g/cm3)
CuO-280OC
a(Å)=4.6858(5)
b(Å)=3.4232(1)
c(Å)=5.1291(3)
beta(°)=99.47258
93.1
5.1291(3)
CuO-510 oCCu(NO3)2
a(Å)= 4.6871(0)
b(Å)= 3.4266(7)
c(Å)= 5.1322(1)
beta(°)=99.54
108.4
6.500
CuO-650 oC
a(Å)= 4.6848(6)
b(Å)= 3.4235(0)
c(Å)= 5.1291(2)
beta(°)=99.46607
131.1
6.511
CuO-510 oCCuSO4
a(Å)= 4.6886(7)
b(Å)= 3.4219(5)
c(Å)= 5.1313(7)
beta(°)=99.496
100.1
6.507
Reference: S. Grugeon, S. Laruelle, R. Herrera-Urbina, L. Dupont, P.
Poizot, J-M. Tarascon, Journal of the Electrochemical Society, 148
(4) A285-A292 (2001)
10
Scanning electron microscopy (SEM)
Sample 1-280oC
Sample 4-510oC
Cauliflower
-like shape
Sample 5-410oC
Sample 3-650oC
11
Scanning electron microscopy (SEM)
CuO reheated to 750 oC prepared from: CuO750 oC MSM; bar scale: 1 µm
CuO heated directly to 750 oC : bar scale:
1 µm
Sample 6-750oC
Spongy
shape
Change in
morphology
Drop in
capacity
Needle
shape
12
Cyclic Voltammetry
0.005V
 Cathodic peaks
3.0V
0.001
1st Cycle
2nd Cycle
5th Cycle
Current / A
0.000
-0.001
-0.002
CuO Sample 4 Cell 2
-0.003
-0.004
 Reduction:
 Cu2+ to Cu metal
 Anodic peaks
 Oxidation:
 Cu metal to Cu2+
 2nd and 5th
Cycles overlap a
lot
-0.005
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Voltage / V
Sample 4: CuO-510 oC -CuSO4 MSM
The peak density
decreased for
the 5th Cycle
13
Galvanostatic Cycling
- To test the capacity of the cell
Capacity (mAh/g)
Discharge Capacity
Charge Capacity
Coulombic Efficiency
800
600
400
200
0
0
10
20
30
40
1000
800
600
400
200
0
100
90
80
CuO Sample 3 Cell 2 P4100
70
60
50
Discharge Capacity
40
Charge Capacity
30
Coulombic Efficiency
20
10
Cu(SO)4·5H2O and0 0.68M
10
20 :0.32M
30 LiCl40with a
LiNO
3
Cycle
number
molar
ratio
Coulombic Efficiency (%)
CuO Sample 4 Cell 2 m2113
1000
100
90
80
70
60
50
40
30
20
10
0
Coulombic Efficiency (%)
1200
Capacity (mAh/g)
1200
of 1:10
Cycle number



Sample 4 – reversible capacity increased.The result is better than
the cell which was heated directly to 750 oC1
Capacities were not as high as cells heated directly to 750oC1
Due to their difference in morphologies
1. Reddy, M. V.; Yu, C.; Fan, J. H.; Loh, K. P.; Chowdari, B. V. R., Li-Cycling Properties of Molten Salt Method Prepared
Nano/Submicrometer and Micrometer-Sized CuO for Lithium Batteries. ACS Appl. Mater. Interfaces 2013, 5 (10), 43614366.
14
1200
Capacity (mAh/g)
1000
CuO Sample 2 Cell 1 P4103
800
Discharge Capacity
Charge Capacity
Coulombic Efficiency
600
400
200
0
0
10
20
30
40
100
90
80
70
60
50
40
30
20
10
0
Coulombic Efficiency (%)
Galvanostatic Cycling
Cycle number
1200
Coulumbic Efficiency (%)
100
90
80
70
60
50
40
30
20
Capacity (mAh/g)
1000
CuO Sample 6 Cell 2 P4095
800
Discharge Capacity
Charge Capacity
Coulombic Efficiency
600
400
200
0
0
10
20
30
Cycle number
40
1200
1100
1000
900
800
700
600
500
400
300
200
100
100
90
80
70
60
50
40
30
20
Columbic Efficiency (%)
Capacity (mAh/g)
Fig: Voltage (0.005-3.0V) vs Capacity of CuO reheated to 750 oC
prepared from (a) CuO-280 oC MSM (b) CuO-510oC-Cu(NO3)2 MSM (c)
15
CuO-750 oC MSM
CuO Sample 6 Cell 2 P4095
Discharge Capacity
Charge Capacity
Coulombic Efficiency
0
10
20
30
Cycle number
40
Conclusion
Synthesized CuO at various
temperature and reheated them to
750 oC
X-Ray Diffraction (XRD)
Scanning Electron
Microscopy (SEM)
Cyclic Voltammetry (CV)
Galvanostatic
Cycling studies (GC)
510 oC using CuSO4
High and stable reversible
capacity
16
Insert your poster here
reserve SLIDES
28
Cyclic Voltammetry
0.0004
0.0004
0.0002
0.0002
1st Cycle
2nd Cycle
5th Cyvle
-0.0002
-0.0004
-0.0006
-0.0008
Current / A
Current / A
0.0000
CuO Sample 1 Cell 2
-0.0010
1st Cycle
2nd Cycle
5th Cycle
0.0000
-0.0002
-0.0004
CuO Sample 2 Cell 1
-0.0006
-0.0012
-0.0008
-0.0014
-0.0016
-0.0010
0.0
0.5
1.0
1.5
2.0
2.5
3.0
0.0
0.5
1.0
Voltage / V
2.0
2.5
3.0
Voltage / V
0.001
0.0005
0.0000
1st Cycle
2nd Cycle
5th Cycle
0.000
-0.0010
-0.0015
-0.0020
CuO Sample 3 Cell 2
-0.0025
Current / A
1st Cycle
2nd Cycle -0.001
5th Cycle
-0.0005
Current / A
1.5
-0.002
CuO Sample 4 Cell 2
-0.003
-0.0030
-0.004
-0.0035
-0.0040
-0.005
0.0
0.5
1.0
1.5
2.0
Voltage / V
2.5
3.0
0.0
0.5
1.0
1.5
2.0
Voltage / V
2.5
3.0
19
Cyclic Voltammetry
0.001
1st Cycle
2nd Cycle
5th Cycle
-0.001
0.0004
1st Cycle
2nd Cycle
5th Cycle
0.0002
0.0000
-0.002
-0.003
CuO Sample 5 Cell 2
-0.004
-0.005
-0.006
Current / A
Current / A
0.000
-0.0002
CuO C2669 Sample 6 Cell 4
-0.0004
-0.0006
-0.0008
-0.007
-0.0010
0.0
0.5
1.0
1.5
2.0
Voltage / V
2.5
3.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Voltage / V
Fig: Cyclic voltammograms of CuO reheated to 750 oC
prepared from (a) CuO-280 oC MSM (b) CuO-510oCCu(NO3)2 MSM (c) CuO-650 oC MSM (d) CuO-510 oC -CuSO4
MSM (e) CuO-410 oC MSM (f) CuO-750 oC MSM
20
Cyclic Voltammetry
0.001
1st Cycle
2nd Cycle
5th Cycle
-0.001
0.0004
1st Cycle
2nd Cycle
5th Cycle
0.0002
0.0000
-0.002
-0.003
CuO Sample 5 Cell 2
-0.004
-0.005
-0.006
Current / A
Current / A
0.000
-0.0002
CuO C2669 Sample 6 Cell 4
-0.0004
-0.0006
-0.0008
-0.007
-0.0010
0.0
0.5
1.0
1.5
2.0
Voltage / V
2.5
3.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
Voltage / V
Fig: Cyclic voltammograms of CuO reheated to 750 oC
prepared from (a) CuO-280 oC MSM (b) CuO-510oCCu(NO3)2 MSM (c) CuO-650 oC MSM (d) CuO-510 oC -CuSO4
MSM (e) CuO-410 oC MSM (f) CuO-750 oC MSM
20