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Structural, morphological and thermo gravimetric analysis of spray pyrolysed Y doped BaCeO3 (BCY) thin films
Under the guidance
Prof. C. H. Bhosale & Dr. L. D. Jadhav
BySnehal U. Dubal
Department of Physics, Shivaji University, Kolhapur - 416 004, India
Outline of Presentation
1. INTRODUCTION
2. EXPERIMENTAL BCY – perovskite structure Synthesis of Yttrium doped Barium Cerate (BCY) thin films by
Spray pyrolysis technique
3. RESULTS AND DICUSSION Thermo gravimetric analysis XRD studies Morphological studies DC- Conductivity
• 4. CONCLUSIONS
Introduction of fuel cell and types of fuel Cell
Fuel cell type Mobile Ion Operating Temperature ◦C
Polymer electrolyte membrane fuel cell (PEMFC)
H+50-100
Alkaline fuel cell (AFC) OH- 50-200
Phosphoric acid fuel cell (PAFC) H+ ~220
Molten carbonate fuel cell (MCFC)
CO32- ~650
Solid oxide fuel cell (SOFC)
O2- OR H+ 500-1000
At Anode H2 → 2H+ + 2e−
At Cathode 1/2O2 +2e− 1/2 O2−
A fuel cell is an electrochemical energy conversion device.
Higher efficiency.
Low cost electrode materials can be used instead of
expensive noble metals such as platinum.
A large variety of fuels can be used including natural
gas, biogas, methanol and ammonia.
Low degradation problem of cell components.
Easy to handle as all the components are in solid
form.
Advantages of SOFC
Chemicals and materialsBCY –perovskite structure
Oxygen atom
Barium atom
Cerium atom
• The different perovskite based materials have
been explored as proton conducting
electrolyte materials for intermediate
temperature SOFCs .
• Three basic materials are BaZrO3, SrZrO3
and BaCeO3.
• BaCeO3 exhibits proton conductivity - 1.8 x
10-2 to 7 x 10-2 𝛀-1 cm-1
• To increase its conductivity and chemical
stability, it is doped with Yttrium at Ceria
sites. Yttrium atom
Three Dimensional View of Perovskite
O
Ba
Ce
A
O3
B
ABO3 - Structure
Proton conduction mechanism
OHVOH ig 2)(2
HOOVOH g 2)(2
Synthesis of Yttrium doped Barium Cerate (BCY) thin films by Spray pyrolysis technique
Solution Concn Substrate Substrate temp. Spray rate
0.1 M Alumina 250 °C 1 ml/min
Chemical-1 Ba (NO3)2
Chemical-2 Ce(NO3)3
Chemical-3 Y(NO3)3
Solvent Water
Schematic view of Spray pyrolysis techniques (SPT)
RESULTS AND DICUSSIONThermo gravimetric analysis
XRD patterns of BCY films annealed at different temperature
AnnealingTemp. °C
Crystallite Size nm
1000 26
900 35
800 11
700 10
a = 8.873Å b = 6.246 Å C = 6.216 Å
JCPDS cardNo. 82-2372
700 °C
800 °C
900 °C
1000 °C
SEM of BCY films
700 °C
1000 °C 900 °C
800 °C
DC-conductivity in (a) air (b) Argon atmosphere
CONCLUSIONS
BCY20 thin electrolyte has been deposited by economical spray pyrolysis technique.
The phase pure and dense film is obtained at 900 °C.
The maximum value of dc conductivity in argon at 600 °C is 2.45 × 10−3 S cm−1.
This method could be extended to form thin electrolyte based SOFC.
• I like to acknowledge the UGC for financial assistance under RGN- fellowship.
Acknowledgment
Thank you