1. Na2S-P2S5 glass-ceramic electrolytes
for sodium batteries at room
Paper Id 239
temperature
Presented by
*Paramjyot Kumar Jha, O. P. Pandey, K. Singh
*Research Scholar
School of Physics and Materials Science
Thapar University, Patiala, Punjab, INDIA
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11/12/2013

2. Outline of presentation
☺ Introduction of Solid Electrolyte
☺ Applications of Solid Electrolyte
☺ Experimental Procedure
☺ Results and Discussion
☺ Conclusions
☺ Acknowledgment
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3. What is electrolyte?
Any substance containing free ions that make
the substance electrically conductive is called
electrolyte.
What is Solid electrolyte?
A solid compound
in which ions migrate
through vacancies or interstices within the
lattice which leads to ionic conductivity.
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4. Characteristics of Solid Electrolyte
۞ 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.
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5. Applications of Solid Electrolyte
Gas Sensors
Fuel Cells
Solid State
batteries
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6. Advantages of solid state batteries over
conventional batteries

7. Superionic glasses for Solid
electrolytes
 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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8. Glass Compositions
xNa2S- (100-x)P2S5
• 35Na2S-65P2S5
NP1
• 40Na2S-60P2S5
NP2
• 45Na2S-55P2S5
NP3
• 50Na2S-50P2S5
NP4
• 55Na2S-45P2S5
NP5
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9. METHODOLOGY
Sample preparation
by melt quenched technique
at 700 ͦ C
Characterization
XRD
DTA/TGA
Raman Spectroscopy
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SEM
Dilatometer
Impedance Spectroscopy
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10. X-ray diffraction of glasses
Intensity (a.u)
55 % Na2S
50 % Na2S
45 % Na2S
40 % Na2S
35 % Na2S
10
20
30
40
50
60
70
80
2 (degree)
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11. Dilatometeric study
-3
1.5x10
-3
dL/L0
2.0x10
1.0x10
5.0x10
-3
35 mol% Na2S
40 mol% Na2S
-4
45 mol% Na2S
50 mol% Na2S
0.0
55 mol% Na2S
50
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100
150
200
Temperature /C
250
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12. Differentiation of Dilatometeric curves for
Glasses
-3
1.5x10
40 mol % Na2S
1.0x10
-3
-5
120 C
-6
d(dL/L )
0
dL/L0
5.0x10
1.0x10
-3
185 C
-3
45 mol% Na2S
-5
168 C
-3
1.6x10
1.2x10
1.5x10
dL/L0
2.0x10
-6
3.0x10
-6
-4
4.0x10
-6
6.0x10
8.0x10
9.0x10
-4
0.0
-5.0x10
-5
0.0
50
1.6x10
100
150
200
Temperature /C
250
0.0
300
50
100
150
200
Temperature /C
250
-3.0x10
300
1.0x10
110 C
-3
5.0x10
170 C
-5
55 mol % Na2S
173 C
-6
1.0x10
-5
-3
5.0x10
-6
8.0x10
-4
0.0
-4
-5.0x10
-6
4.0x10
-1.0x10
-5
-3
1.2x10
d(dL/L )
0
1.6x10
-5.0x10
-1.0x10
-4
-5
-1.5x10
4.0x10
-6
dL/L0
dL/L0
-4
d(dL/L )
0
0.0
8.0x10
-6
-3
50 mol % Na2S
1.2x10
0.0
-6
-1.0x10
d(dL/L )
0
5.0x10
-4
-5
0.0
0.0
50
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100
150
200
Temperature /C
250
-2.0x10
300
-5
50
100
150
200
Temperature /C
250
300
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13. Raman Spectroscopy
60 mol % Na2S
Intensity (a.u.)
55 mol % Na2S
50 mol % Na2S
45 mol % Na2S
250
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500
1279
1164
1011
948
684
620
528
300
379
40 mol % Na2S
35 mol % Na2S
750
1000
1250
1500
-1
Raman shift (cm )
1750
2000
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14. Table 1
35
40
45
50
55
60
Assignment
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
Wave number (cm-1)
Mol %
(Na2S)
1276
1279
1266
1274
1256
νas(PO2)
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15. Differential Thermal Analysis (DTA)
Endo Down /Exo up (V)
Tc
Tg
Tc1
55 mol %
10 C/min
20 C/min
30 C/min
40 C/min
Tg
Endo Down /Exo up (V)
10 C/min
20 C/min
30 C/min
40 C/min
45 mol %
Tm
Tc2
Tm
100
200
300
400
Temperature  C)
τ.Tg = constant
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500
600
100
200
300
400
500
600
700
Temperature  C)
Tg increases means relaxation dynamics in the glass.
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16. Kissinger plot for Tg and Tc at different
heating rates
Linear fit of Tc
Linear fit of Tg
10.5
10.4
10.0
10.0
ln
ln
Linear fit of Tc
Linear fit of Tg
9.5
9.6
9.2
9.0
8.8
1.5
1.6
1.7
-1
1000/T(K )
1.8
1.9
1.5
1.6
1.7
-1
1000/T(K )
1.8
1.9
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.
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17. Crystallization Kinetics Parameters
Glass
Heating
rate
(⁰C/min.)
X = 45
10
∆T =
Ea
Hr =
Tc-Tg (⁰C) (kJ mol-1) (Tc-Tg)/
(Tm-Tc)
68
0.33
Tm
(⁰C)
276
344
547
278
355
552
77
370 (Tg)
0.39
30
283
362
555
79
170 (Tc)
0.40
40
286
370
559
84
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
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Tc
(⁰C)
20
X = 55
Tg
(⁰C)
264
345
626
81
0.29
0.44
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18. X-ray diffraction of glass-ceramics
 Na3PS4
Rest NaPO3
* Na2S2O3
*
Intensity (a.u.)


55 % Na2S


50 % Na2S


45 % Na2S

40 % Na2S

*
*
*
10

20


30

40
50
60
70
80
 (degree)
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19. Density Variation
2.36
Density (g/cc)
2.32
2.28
2.24
40
45
50
55
Mol % Na2S
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20. UV-Visible Spectroscopy of Glass-ceramics
40 % Na2S
45 % Na2S
50 % Na2S
( h  )
2
55 % Na2S
1
2
3
4
5
h (eV)
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21. Table 2
S.
Glass
Bulk
No. composition Density Band resista Ionic
(Mol %) ρ (g/cc) gap
nce conduct
(eV) (Ω) ×
ivity
103
(S/cm)
× 10-5
Na2S P2S5
Volume fractions
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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22. FE-SEM micrographs of Glass-ceramics
X = 40
X = 45
X = 50
X = 55
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23. Conclusions
• 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.
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24. 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.
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25. Thank you for your Kind
Attention
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