1. Interdispersed YSZ-Zn doped CeO2-NiO-Ag
Composites for Anode Supported Intermediate
Temperature Solid Oxide Fuel Cells
Bhasker Soni and Somnath Biswas*
*Email: drsomnathbiswas@gmail.com
Department of Physics, The LNM Institute of Information Technology
(Deemed University)
Jaipur – 302031, India
4th ICAER, IIT Bombay, 2013
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2. Lecture Plan





Introduction
Experimental details
Results
Future Work
Conclusions
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3. Introduction
 Global energy requirements are increasing rapidly
 Energy crisis
 Green house effect
 Global warming
 Limited energy sources : Conventional and non-conventional
 Drawbacks with the present power technologies
 Lack of efficient technology
Fuel cells technology
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4. Introduction
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5. Introduction
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6. Introduction
Presently used technology
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7. Introduction

Fuel cell : An electrochemical device that
converts energy produced from a
chemical reaction into electrical energy.
This chemical reaction is not a combustion
process

Chemical Energy  Electrical Energy
Working :
Anode: 2H2 + 2O= =4e- + 2H2O
Cathode: O2 + 4e- = 2O=
Over All: 2H2 + O2 = 2H2O
Electricity is generated with H2O as
byproduct.


Animation taken from Solid state energy conversion Alliance (SECA)
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8. Introduction
Types of Fuel Cells






PEMFC (proton exchange membrane)
DMFC (direct methanol)
AFC (alkaline)
PAFC (phosphoric acid)
MCFC (Molten Carbonate)
SOFC (solid oxide)
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9. Introduction



SOFC : Solid Oxide Fuel Cell.
Working :
Anode: 2H2 + 2O= =4e- + 2H2O
Cathode: O2 + 4e- = 2O=
Over All: 2H2 + O2 = 2H2O
Electricity is generated with H2O as
byproduct.
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10. Advantages
 High conversion efficiency 45%(up to *85% energy efficiency
when combined with gas turbine).
 Combined heat and power.
 No need for electrolyte management.
 Ample fuel flexibility (Nat. gas/methane
fuelled).
 Non Polluting - no NOx/SOx
 Long life, modular.
 Quiet in operation.
 Load flexible.
 Low cost ceramic and non noble metal materials.
SOFCs
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11. Disadvantages
 High operating temperature (800 °C – 1000 °C).
 Less material selection options.
Thermal stress.
 Degradation and delamination.
 Long start up time.
 Difficulty in stacking cells.
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12. Experimental Details
Synthesis
 Synthesis of nanoparticles
 Synthesis of YSZ-CZO-NiO-Ag nanocomposites.
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13. Experimental Details
Synthesis of nanoparticles of 8YSZ, Ni:NiO, Zn doped CeO2(CZO)
 Sol-gel type chemical precursor
Nitrate solutions of
method.
 Y(NO3)3·6H2O
 pH: Basic medium
 ZrO(NO3)2·H2O
 Ni(NO3)2.6H2O
 Reaction Temperature: 60 – 70 C
C
 Ce(NO3)3·6H2O
 Zn(NO3)3·6H2O
 Amorphous dried precursor.
 Calcined at 400 C,500 C and 600 C.
Magnetic
Stirrer
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14. Experimental Details
40
50
(331)
(420)
(222)
(400)
80
50
70
80

60
Diffraction Angle, 2 (degree)

70

(222)
 NiO
 Ni

40
(400)
60
(311)
(220)
(111)


30
(311)
50
(200)
(c)
20
70
(220)
40
(200)
30
(111)
20
60
(220)
(200)
(b)
30
(111)
Intensity (arb. unit)
20
(311)
(220)
(200)
(a)
(111)
Synthesis of nanoparticles of 8YSZ, Ni:NiO, Zn doped CeO2(CZO)

80
Fig. 1 XRD plots of (a) 10 mol% CZO, (b) 8 mol% YSZ, and (c) Ni : NiO (core-shell) nanoparticles obtained
after heat treatment of the corresponding precursors at 400°C, 500°C and 600°C, respectively in ambient air.
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15. Experimental Details
(a)
(b)
(c)
(d)
Fig. 2 Typical HRTEM images of (a, b) 8 mol% YSZ, (c) 10 mol% CZO, and (d) Ni:NiO nanoparticles.
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16. Experimental Details
Synthesis of nanoparticles of 8YSZ, Ni:NiO, Zn doped CeO2(CZO)
(a)
(b)
Fig. 3 FESEM images of (a) 10 mol% CZO and (b) 8 mol% YSZ nanoparticles.
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17. Experimental Details
Synthesis of YSZ-CZO-NiO-Ag nanocomposites
Structural
Electrical
Sample
Code
YSZ
(vol%)
CZO
(vol%)
Ni : NiO
(vol%)
A
20
20
60
B
25
25
50
C
30
30
40
D
35
35
30
 Series of composite samples.
 Ball milled for 5 h.
 Starch as pore former.
 Ball to Powder ratio 10 : 1.
Table 1. Compositional details of YSZ-CZO-Ni:NiO composites.
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18. Experimental Details
Synthesis of YSZ-CZO-NiO-Ag nanocomposites
Structural
Electrical
Sample
Code
YSZ
(vol%)
CZO
(vol%)
Ni : NiO
(vol%)
A
20
20
60
B
25
25
50
C
30
30
40
D
35
35
30
 TEC of YSZ : 10.5 x10-6 K-1.
 TEC of Ni : 13.0 x10-6 K-1.
 TEC of CeO2 : 12.58 x10-6 K-1
TEC of Ag : 18.0 x10-6 K-1.
Table 1. Compositional details of YSZ-CZO-Ni:NiO composites.
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19. Experimental Details
(200)
(111)

CZO
 YSZ
 NiO
Ni




(220)
(311)
(220)
(222)
•
(311)

(311)
•
(220)
(220)
(200)
(200)
(200)
Intensity (arb. unit)
(A)
(111)
(111)
•





•

(B)
(C)
(D)
20
30
40
50
60
70
80
Diffraction Angle, 2 (degree)
Fig. 4 XRD plots of YSZ-CZO-Ni:NiO nanocomposites of compositions as shown in Table 1.
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20. Experimental Details
 Porosity measurement using ASTM C20 technique
 Sample is oven dried at 110 ⁰ C till constant weight is achieved.
 Submerged in boiling water for 4 h.
 When suspended in water, the weight is measured to calculate specific
gravity.
 Porosity (P,%) = (W – D)/V x 100 = 38.4% (sample A)
= 38.7% (sample C)
where, W = saturated weight
D = dry weight
V = volume of sample
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21. Future Work
 Oxygen Permeability.
 Impedance Spectroscopy.
 I-V and I-P characteristics : DC Four Probe.
 Mechanical properties : Ductility and strength, Elastic properties, CTE,
Poisson's ratio, creep analysis etc.
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22. Conclusions
 Composite anode materials of YSZ-CZO-Ni:NiO for intermediate temperature
SOFCs have been developed by mechanical attrition method.
 From XRD studies, the crystal structure of YSZ, CZO and Ni:NiO has been
confirmed to be cubic in nature.
 FESEM and HRTEM micrographs reveal the fine structure of the particles.
 Electrical and electro-chemical analyses of the samples are currently being
performed.
 Successful development of this material would decrease the polarization losses at
anode and aid in enhancing the cell performance at lower temperatures.
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23. Acknowledgements
The authors sincerely thank (i) Tata Institute of Fundamental Research
(TIFR), Mumbai (ii) UGC-DAE Consortium for Scientific Research, Indore,
(iii) Sathyabama University, Chennai, and (iv) Sophisticated Analytical
Instrument Facility (SAIF), North-Eastern Hill University (NEHU), Shillong
for providing us the instrumental facilities.
We also thank The LNM Institute of Information Technology for their
financial support to carry out the research work.
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24. THANK YOU
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