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Na2S-P2S5 glass-ceramic electrolytes for sodium batteries at room temperature
Presented by
*Paramjyot Kumar Jha, O. P. Pandey, K. Singh
*Research ScholarSchool of Physics and Materials ScienceThapar University, Patiala, Punjab, INDIA
ICAER 2013 11/12/2013
Paper Id 239
Outline of presentation
☺ Introduction of Solid Electrolyte
☺ Applications of Solid Electrolyte
☺ Experimental Procedure
☺ Results and Discussion
☺ Conclusions
☺ Acknowledgment
ICAER 2013 11/12/2013
Any substance containing free ions that make
the substance electrically conductive is called
electrolyte.
A solid compound in which ions migrate through
vacancies or interstices within the lattice which
leads to ionic conductivity.
What is electrolyte?
What is Solid electrolyte?
ICAER 2013 11/12/2013
۞ Availability of large number of free ions.
۞ Requirement of low activation energy for the movement
of ions into neighbouring sites.
۞ Three dimensional networking for free movement of the
ions.
۞ The anion framework should be highly polarizable.
ICAER 2013 11/12/2013
Characteristics of Solid Electrolyte
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Applications of Solid Electrolyte
Gas Sensors
Fuel Cells
Solid State batteries
Advantages of solid state batteries over conventional batteries
Higher ionic conductivities
Isotropic properties
No grain and hence no grain boundaries
Exhibits ionic conductivity in the range of
10-1 to 10-4 S/cm at room temperature.
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Superionic glasses for Solid electrolytes
• 35Na2S-65P2S5 NP1
• 40Na2S-60P2S5 NP2
• 45Na2S-55P2S5 NP3
• 50Na2S-50P2S5 NP4
• 55Na2S-45P2S5 NP5ICAER 2013 11/12/2013
Glass Compositions xNa2S- (100-x)P2S5
Sample preparationby melt quenched technique
Characterization
XRD DTA/TGA DilatometerSEM
Impedance Spectroscopy
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Raman Spectroscopy
METHODOLOGY
at 700 $ C
10 20 30 40 50 60 70 80
35 % Na2S
40 % Na2S
45 % Na2S
55 % Na2S
50 % Na2S
2 (degree)
In
tensity (a.u
)
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X-ray diffraction of glasses
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Dilatometeric study
50 100 150 200 250
0.0
5.0x10-4
1.0x10-3
1.5x10-3
2.0x10-3
Temperature /C
dL/L
0
35 mol% Na2S
40 mol% Na2S
45 mol% Na2S
50 mol% Na2S
55 mol% Na2S
50 100 150 200 250 300
0.0
5.0x10-4
1.0x10-3
1.5x10-3
2.0x10-3
168 C
Temperature /C
dL/L
0
120 C
-1.0x10-5
-5.0x10-6
0.0
5.0x10-6
1.0x10-5
1.5x10-5
d(d
L/L
0)
40 mol % Na2S
50 100 150 200 250 300
0.0
4.0x10-4
8.0x10-4
1.2x10-3
1.6x10-3 45 mol% Na2S
Temperature /C
dL/L
0
-3.0x10-6
0.0
3.0x10-6
6.0x10-6
9.0x10-6
d(d
L/L
0)
185 C
50 100 150 200 250 300
0.0
4.0x10-4
8.0x10-4
1.2x10-3
1.6x10-3
50 mol % Na2S
170 C110 C
-2.0x10-5
-1.5x10-5
-1.0x10-5
-5.0x10-6
0.0
5.0x10-6
1.0x10-5
dL
/L0
Temperature /C
d(d
L/L
0)
50 100 150 200 250 300
0.0
4.0x10-4
8.0x10-4
1.2x10-3
1.6x10-3
55 mol % Na2S
-1.0x10-5
-5.0x10-6
0.0
5.0x10-6
1.0x10-5173 C
Temperature /C
dL/L
0
d(d
L/L
0)
ICAER 2013 11/12/2013
Differentiation of Dilatometeric curves for Glasses
250 500 750 1000 1250 1500 1750 2000
1279
1164
1011
948
684
620
528
379
300
35 mol % Na2S
40 mol % Na2S
45 mol % Na2S
50 mol % Na2S
55 mol % Na2S
60 mol % Na2S
Inte
nsity (a.u
.)
Raman shift (cm-1)
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Raman Spectroscopy
Mol %(Na2S)
35 40 45 50 55 60 Assignment
Wave numb
er (cm-1)
300 294 300 307 303 343 νas(P-S-P)
379 375 386 382 384 487 stretching vibration of
the P-S bond
528 540 … … … 539 νs(P-S-P)
620 621 … … … 878 νs(POP)
684 690 684 683 683 690 stretching vibrations
of P = S mode
… … … … … 948 SO32- ion
… … … 1011 … 1011 νs(SO42- )
1164 1162 1164 1161 1164 1151 νs(PO2)
1279 1276 1279 1266 1274 1256 νas(PO2)
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Table 1
100 200 300 400 500 600
Tm
Tg
Tc
Endo
Dow
n /E
xo u
p (
V)
Temperature C)
10 C/min 20 C/min 30 C/min 40 C/min
45 mol %
100 200 300 400 500 600 700
Endo
Dow
n /E
xo u
p (
V)
Tg
Tm
Tc1
Tc2
Temperature C)
10 C/min 20 C/min 30 C/min 40 C/min
Tc2
55 mol %
τ.Tg = constant Tg increases means relaxation dynamics in the glass.
ICAER 2013 11/12/2013
Differential Thermal Analysis (DTA)
1.5 1.6 1.7 1.8 1.9
9.0
9.5
10.0
10.5 Linear fit of Tc Linear fit of Tg
ln
1000/T(K-1)1.5 1.6 1.7 1.8 1.9
8.8
9.2
9.6
10.0
10.4
ln
1000/T(K-1)
Linear fit of Tc Linear fit of Tg
ln [Tc2⁄β] = Ea⁄(RTc ) + constant
Where, Tc is the peak crystallization temperature, R is the gas constant and β is heating
rate. A graph between ln [Tc2⁄β] and 1000/Tc gives straight line and from its slope (Ea/R)
activation energy of the crystallization is obtained. ICAER 2013 11/12/2013
Kissinger plot for Tg and Tc at different heating rates
Glass Heating rate
(⁰C/min.)
Tg (⁰C)
Tc
(⁰C)Tm
(⁰C)∆T =
Tc-Tg (⁰C)Ea
(kJ mol-1)Hr =
(Tc-Tg)/(Tm-Tc)
X = 45 10 276 344 547 68 0.33
20 278 355 552 77 370 (Tg) 0.39
30 283 362 555 79 170 (Tc) 0.40
40 286 370 559 84 0.44
X = 55 10 252 318 616 66 264 (Tg) 0.22
20 257 325 621 68 165 (Tc) 0.22
30 260 338 624 78 0.27
40 264 345 626 81 0.29
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Crystallization Kinetics Parameters
10 20 30 40 50 60 70 80
*
*
*
*
Na3PS
4* Na2S2O3Rest NaPO
3
Inte
nsi
ty (
a.u
.)
(degree)
55 % Na2S
50 % Na2S
45 % Na2S
40 % Na2S
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X-ray diffraction of glass-ceramics
40 45 50 55
2.24
2.28
2.32
2.36
Density (g/c
c)
Mol % Na2S
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Density Variation
1 2 3 4 5h (eV)
(h)2
40 % Na2S
45 % Na2S
50 % Na2S
55 % Na2S
ICAER 2013 11/12/2013
UV-Visible Spectroscopy of Glass-ceramics
S. No.
Glass compositio
n(Mol %)
Densityρ (g/cc)
Band gap (eV)
Bulk resista
nce(Ω) × 103
Ionic conduct
ivity (S/cm) × 10-5
Volume fractions
Na2S P2S5 NaPO3 Na2S2O3 Na3PS4
1 40 60 2.24 3.60 118.2 0.12 85 7 8
2 45 55 2.29 3.48 72.8 0.18 81 9 10
3 50 50 2.33 3.35 6.11 2.0 74 12 14
4 55 45 2.35 2.99 1.84 6.0 69 16 15
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Table 2
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FE-SEM micrographs of Glass-ceramics
X = 40
X = 50
X = 45
X = 55
• All sample shows halo pattern indicating its amorphous nature.
• Glass samples for x = 45 and x = 55 mol % Na2S shows good
stability.
• Glass-ceramics sample shows mainly three phases.
• With increase in Na2S content the most conducting phase Na3PS4 is
found to be increased.
• The ionic conductivity of present samples are found to be in the
order of 10-5 S/cm at room temperature.
• SEM micrographs reveals dense and well grown crystals. ICAER 2013 11/12/2013
Conclusions
ICAER 2013 11/12/2013
Acknowledgment
• I would like to thank my Supervisors Dr. Kulvir Singh (Professor &
Head) and Dr. O. P. Pandey (Senior Professor), Thapar University,
Patiala for their Guidance.
• I would like to thank Department of Science and Technology (DST),
New Delhi for the financial support.
• I would like to thank Technical Education Quality Improvement
Programme (TEQIP), Thapar University, Patiala for the travel
support.
• I would like to thank the Organizer (Dr. P. C. Ghosh ) of ICAER who
has given me an opportunity to present my work here.
ICAER 2013 11/12/2013
Thank you for your Kind Attention
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