nanofiber-base refrigeration · 2018. 8. 7. · pedot • the electrical conductivity does not...

Nanofiber-base Refrigeration

Alexandria Trevino and Bret Flanders

Department of Physics

Kansas State University

TCTH

Seebeck Effect

∆V

Thermoelectric Refrigeration

Directional Growth of polypyrrole and polythiophene wires Prem S. Thapa, Deok Jin Yu, James P. Wicksted, Jeffrey A. Hadwiger, Joseph N. Barisci, Ray H. Baughman, and Bret N. Flanders

Directional electrochemical nanowire assembly

Thapa, P. S., Yu, D. J., Wicksted, J. P., Hadwiger, J. A., Barisci, J. N., Baughman, R. H., & Flanders, B.

N. (2009). Directional growth of polypyrrole and polythiophene wires. Applied Physics Letters,94(3),

033104. doi:10.1063/1.3072611

• Voltage-amplitude and frequency induces growth

• Knobby structure

• 𝐸𝑙𝑒𝑐𝑡𝑟𝑖𝑐𝑎𝑙 𝑐𝑜𝑛𝑑𝑢𝑐𝑡𝑖𝑣𝑖𝑡𝑦 =𝑙

𝑅𝐴

PEDOT:Heparin Growth

40 μm 20 μm

AU, WE AU, CE

Monomer Solution

AU, WE

AU, CEVoltage

Atomic Force Microscopy (AFM)

5 μm

1 µm

595 nm wire

963 nm wire

Diameter (nm)

400 600 800 1000 1200

Co

un

t

0

10

20

30

40

50

L=74.66 𝜇m

L=52.70 𝜇m

L=47.23 𝜇m

∆𝑉 − The voltage drop across R when I flows though it

100 𝜇M Heparin content

Length (𝛍m) Diameter (nm) Resistance (M𝞨) Conductivity (S cm^-1)

Wire 1 64.03 993 1.07 0.770

Wire 2 64.30 830 0.988 1.20

Wire 3 62.96 964 0.813 1.06

Wire 4 44.55 973 0.858 0.698

Wire 5 57.15 960 1.13 0.700

Wire 6 49.81 622 1.26 1.30

L=44.09 𝜇m

L=62.78 𝜇m

L=42.68 𝜇m

L=43.64 𝜇m

Length (𝛍m) Diameter (nm) Resistance (M𝞨) Conductivity (S cm^-1)

Wire 1 42.68 1362 0.322 0.910

10 𝜇m Heparin content

ConclusionHeparin

PEDOT

• The electrical conductivity does not depend on diameter, resistance,

and length.

• We should see a consistency with the electrical conductivity

of wires grown at the same conditions.

Future Work• Continue pursing decreasing the heparin content

• Test the electrical conductivity of PEDOT:

Heparin at different temperatures

• Test the thermal conductivity

• PEDOT: Tosylate

Acknowledgements

• Bret Flanders

• Krishna

• Gobind

• NSF

• K-State

• REU students

Questions?

5 μm

1 µm

Length

(𝛍m)

Diameter

(nm)

Resistance

(M𝞨)

Conductivity

(S cm^-1)

Wire 1 42.68 1362 0.322 0.910

L=74.66 𝜇m

L=52.70 𝜇m

L=47.23 𝜇m

L=44.09 𝜇m

L=62.78 𝜇m

L=42.68 𝜇m

L=43.64 𝜇m

Diameter (nm)

400 600 800 1000 1200

Co

un

t

0

10

20

30

40

50

20 μm

Length

(𝛍m)

Diameter

(nm)

Resistance

(M𝞨)

Conductivity

(S cm^-1)

Wire 1 64.03 993 1.07 0.770

Wire 2 64.30 830 0.988 1.20

Wire 3 62.96 964 0.813 1.06

Wire 4 44.55 973 0.858 0.698

Wire 5 57.15 960 1.13 0.700

Wire 6 49.81 622 1.26 1.30