polymer-based thermoelectrics

Polymer-based Thermoelectric Devices

School of Chemical EngineeringPurdue UniversityThursday August 7, 2014

Stuart W. A. Hilsmier, Edward P. Tomlinson, and Bryan W. Boudouris

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Need for Waste Energy Recovery

Source: Lawrence Livermore National Laboratory (www.llnl.gov)1. Introduction (1 of 4)2. Methods (2)3. Results (1)4. Conclusion (1)

Fundamentals of Thermoelectric Materials

𝑧𝑇=𝜎𝑆2𝜅 𝑇

Used to compare efficiency of materials

Parameters

Seebeck Coefficient (S): Measures the amount of energy an electron carries across the material

Electrical Conductivity (σ): Measure of the ability for electrons to move through the material

Thermal Conductivity (κ): Measures how easily heat can move through the material

Material Figure of Merit (zT)

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1. Introduction (2 of 4)2. Methods (2)3. Results (1)4. Conclusion (1)

Uses of Thermoelectric Devices

Reduce Weight

Improve efficiency

Reliable

1. Introduction (3 of 4)2. Methods (2)3. Results (1)4. Conclusion (1)

Organic Molecules in Thermoelectric Device

Poly(2,2,6,6-tetramethyl-1-piperidinyloxy-4-yl methacrylate) PTMA

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Testing films doped with 4-ethylbenzenesulfonic acid EBSA

• PTMA previously used in solid-state[3]

• Has well-documented conductivity[1-2]

• Question: What effects will doping PTMA with EBSA have on its conductivity, Seebeck coefficient, and thermoelectric power factor?

1. Introduction (4 of 4)2. Methods (2)3. Results (1)4. Conclusion (1)

From Solution to Device

Prepare solution• Mass compounds

• Add solvent

• Stir until dissolved

Heat to evaporate solvent

Paint silver contacts on

Apply solution to substrate

1. Introduction (4)2. Methods (1 of 2)3. Results (1)4. Conclusion (1)

Conductivity and Seebeck Testing

Current

Voltage

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Voltage

ΔT

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1. Introduction (4)2. Methods (2 of 2)3. Results (1)4. Conclusion (1)

Results

1. Introduction (4)2. Methods (2)3. Results (1 of 1)4. Conclusion (1)

Mass Percent EBSA vs Conductivity

Conclusions and Future Work

1. Introduction (4)2. Methods (2)3. Results (1)4. Conclusion (1 of 1)

• Conductivity increases with larger mass percent of EBSA

• Seebeck data necessary to determine power factor of devices

Percent EBSA vs Seebeck and Power Factor (Example Data)

References

1. Rostro, L.; Baradwaj, A. G.; Boudouris, B. W. ACS Appl. Mater. Interfaces 2013, 5, 9896–9901.

2. Rostro, L.; Wong, S. H.; Boudouris, B. W. Macromolecules 2014, 47, 3713–3719.3. Yonekuta, Y.; Susuki, K.; Oyaizu, K.; Honda, K.; Nishide, H. J. Am. Chem. Soc.

2007, 129, 14128–14129.

Acknowledgements