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Sevda Akay Sevda Akay Fatih University, Istanbul, TURKEY Proton Conductivity Studies of Novel Organic Proton Conductivity Studies of Novel Organic Polymer Polymer
Sevda AkaySevda Akay
Fatih University, Istanbul,TURKEY
Proton Conductivity Studies of Novel OrganicProton Conductivity Studies of Novel OrganicPolymerPolymer
Content
Fuel Cells
Proton Exchange Membrane
Benzimidazole Nitronyl Nitroxides
Synthesis of Novel Organic Polymer (SBNN1)
Electrochemical Impedance Analysis of SBNN1
Conclusions
Acknowledgement
Fuel CellsCells
http://www.carblogindia.com/wpcontent/uploads/2011/02/fuelcell_thumb.jpg
What is function of protonexchange membrane (PEM) infuel cells?
Benzimidazole Nitronyl Nitroxides
-Analogues of nitronyl nitroxide radicals (NNs)-Highly resonance stabilized radicals (two equivalent NO groups and oflarge negative charges on O atom)-High spin density
Proton Conductivity Mechanismof SBNN1
N
N
O
O
O
H
H+
N
N
O
O
O
H
N
N
O
O
O
H ...
......
Thermal Stability of SBNN1
0 100 200 300 400 500 600 700 800
20
30
40
50
60
70
80
90
100
110
We
igh
t(%
)
Temperature (oC)
Commercial PolymerSBNN1
Purchased aldehyde hasbeen found to retain 100% of the mass up to about250 oC. It was observed tolose 5 % of its mass at 340oC, about 62 % at 500 oC,
SBNN is stable up to 150°C, it has lost some massgradually from beginningof 100 °C. It only lost 5%of its mass upto 240oCwhic is mostly associatedwith absorbed water.
The mass loss becamemore pronounced after400 oC. This polymer lost51 % of its mass at 500oC.
Impedance MeasurementsComparison between Nafion and SBNN1
0 1 2 30,0
0,5
1,0
1,5
-Z
''/M
Z' /M
SBNN1, N2
Nafion,N2
0 100 200 300 400 5000
100
200
Z' /M
SBNN1
Nafion
air
Measurements in hydrogenMeasurements of SBNN1 in dry H2 show that the materialSBNN1 has proton conductivity, which increases with theincrease of the gas flow
0 250 500 7500
150
300
40% H2
Z' / M
25% H230% H2
SBNN1, dry H2, room tCo
Impedance diagram of sample SBNN1 in dry hydrogen at room temperature as a function of theflow:
64 µl/min (○); 48 µl/min (○) , 40 µl/min (○)
demonstrate the existence of protonconductivity in SBNN1.
0 200 400 600 800 10000
100
200
300
400
500
Z' /M
air SBNN1N2
48l/min,dry H2
Impedance diagram of sample Bu1 in different gases:air (○); N2 (▲) and dry H2 (◊)
Conclusion
• The results obtained by impedance spectroscopymeasurements of SBNN1 show that the material hasproton conductivity. It is much lower than the onemeasured on Nafion samples prepared by the sametechnological procedure.
Acknowledgements
• Prof. Dr. Zdravko Stoynov
• Prof. Dr. Daria Vladikova
• Assoc. Prof. Dr. Burak Esat
• Dr. Emiliya Mladenova
• Ivaylo Genov
Thank you for listeningThank you for listening……
Synthesis of Novel Organic Polymer(SBNN1)
