16 Magnetic Fluids for Thermoelectricity
399
With R exp the experimentally determined resistance of the cell (from an I-V curve,
for example), l and A are the thermocell constant (length and the effective electrode
area, respectively) and Nu is the Nusselt number, which equals to unity in the absence
of convection. Note that while the convection (Nu > 1) will increase the effective
thermal conductivity, it also helps to increase the mass transport of the redox couples
(thus reduces the R exp ). In certain cases, it is found that the reduction in R exp is
larger than the increase in k, resulting in the enhancement of ZT* of the thermocell
[39, 50]. Therefore, in addition to improving the materials’ intrinsic thermoelectric
property, many opportunities exist in the device engineering (cell dimensions, heating
directions, etc.) for improving the performance of liquid thermocells.
Last, but not least, the application of magnetic field is known to increase the
Soret coefficients of ferrofluids and influence the layering behaviour of nanoparticles
near the electrodes. These experimental observations further encourage the use of
magnetic nanoparticles’ unique and tunable properties [51] in the development of
magnetothermoelectric energy conversion applications.
References
1. C.B. Vinning, An inconvenient truth about thermoelectrics. Nat. Mater. 8, 83 (2009)
2. J.P. Heremans et al., When thermoelectrics reached the nanoscale. Nat. Nanotechnol. 8, 471
(2013)
3. A.I. Hochbaum et al., Enhanced thermoelectric performance of rough silicon nanowires. Nature
451, 163 (2007)
4. L.D. Hicks et M.S. Dresselhaus, Effect of quantum-well structures on the thermoelectric figure
of merit. Phys. Rev. B. 47, 12727–12731 (1993)
5. A. Fina, S. Colonna, L. Maddalena et M. Tortello, A facile and low environmental impact
approach to prepare thermally conductive nanocomposites based on polylactide and graphite
nanoplatelets. ACS Sustain Chem Eng (2018). https://doi.org/10.1021/acssuschemeng.8b0
3013
6. D. Zhao, H. Wanga, Z. U. Khana, J. C. Chen, R. Gabrielssona, M.P. Jonssona, M. Berggrena
et X. Crispin, Ionic thermoelectric supercapacitor. Energy Environ. Sci. 9, 1450 (2016).
7. V. Zinovyeva, S. Nakamae, M. Bonetti, et M. Roger, Enhanced thermoelectric power in ionic
liquids. Chem. Electr. Chem. (2013). https://doi.org/10.1002/celc.201300074
8. M. Hayyan et al., J. Ind Eng. Chem. 19, 106 (2013)
9. S. Uhl et al., J. Electron. Mater. 43, 3758 (2014)
10. M.F. Dupont, D.R. MacFarlane et J.M. Pringle, Thermo-electrochemical cells for waste heat
harvesting—progress and perspectives. Chem. Comm. (2017)
11. T.J. Salez, B.T. Huang, M. Rietjens, M. Bonetti, C. Wiertel-Gasquet, R.M. Gasquet, C.L.
Filomeno, E. Dubois, R. Perzynski et S. Nakamae, Can charged colloidal particles increase
the thermoelectric energy conversion efficiency? Phys. Chem. Chem. Phys. (2017). https://doi.
org/10.1039/C7CP01023K.
12. C. Goupil, W. Seifert, K. Zabrocki, E. Müller et G.J. Snyder, Thermodynamics of thermoelectric
phenomena and applications. Entropy. 13, 1481–1517 (2011)
13. J. Agar et J. Turner, Thermal diffusion in solutions of electrolytes. Proc. R. Soc. Lond. A Math.
Phys; Eng. Sci. 255, 307–330 (1960)
14. S. Di Lecce et F. Bresme, Thermal polarization of water influences the thermoelectric response
of aqueous solutions. J. Phys. Chem. B. 122, 1662–1668 (2018)
399
With R exp the experimentally determined resistance of the cell (from an I-V curve,
for example), l and A are the thermocell constant (length and the effective electrode
area, respectively) and Nu is the Nusselt number, which equals to unity in the absence
of convection. Note that while the convection (Nu > 1) will increase the effective
thermal conductivity, it also helps to increase the mass transport of the redox couples
(thus reduces the R exp ). In certain cases, it is found that the reduction in R exp is
larger than the increase in k, resulting in the enhancement of ZT* of the thermocell
[39, 50]. Therefore, in addition to improving the materials’ intrinsic thermoelectric
property, many opportunities exist in the device engineering (cell dimensions, heating
directions, etc.) for improving the performance of liquid thermocells.
Last, but not least, the application of magnetic field is known to increase the
Soret coefficients of ferrofluids and influence the layering behaviour of nanoparticles
near the electrodes. These experimental observations further encourage the use of
magnetic nanoparticles’ unique and tunable properties [51] in the development of
magnetothermoelectric energy conversion applications.
References
1. C.B. Vinning, An inconvenient truth about thermoelectrics. Nat. Mater. 8, 83 (2009)
2. J.P. Heremans et al., When thermoelectrics reached the nanoscale. Nat. Nanotechnol. 8, 471
(2013)
3. A.I. Hochbaum et al., Enhanced thermoelectric performance of rough silicon nanowires. Nature
451, 163 (2007)
4. L.D. Hicks et M.S. Dresselhaus, Effect of quantum-well structures on the thermoelectric figure
of merit. Phys. Rev. B. 47, 12727–12731 (1993)
5. A. Fina, S. Colonna, L. Maddalena et M. Tortello, A facile and low environmental impact
approach to prepare thermally conductive nanocomposites based on polylactide and graphite
nanoplatelets. ACS Sustain Chem Eng (2018). https://doi.org/10.1021/acssuschemeng.8b0
3013
6. D. Zhao, H. Wanga, Z. U. Khana, J. C. Chen, R. Gabrielssona, M.P. Jonssona, M. Berggrena
et X. Crispin, Ionic thermoelectric supercapacitor. Energy Environ. Sci. 9, 1450 (2016).
7. V. Zinovyeva, S. Nakamae, M. Bonetti, et M. Roger, Enhanced thermoelectric power in ionic
liquids. Chem. Electr. Chem. (2013). https://doi.org/10.1002/celc.201300074
8. M. Hayyan et al., J. Ind Eng. Chem. 19, 106 (2013)
9. S. Uhl et al., J. Electron. Mater. 43, 3758 (2014)
10. M.F. Dupont, D.R. MacFarlane et J.M. Pringle, Thermo-electrochemical cells for waste heat
harvesting—progress and perspectives. Chem. Comm. (2017)
11. T.J. Salez, B.T. Huang, M. Rietjens, M. Bonetti, C. Wiertel-Gasquet, R.M. Gasquet, C.L.
Filomeno, E. Dubois, R. Perzynski et S. Nakamae, Can charged colloidal particles increase
the thermoelectric energy conversion efficiency? Phys. Chem. Chem. Phys. (2017). https://doi.
org/10.1039/C7CP01023K.
12. C. Goupil, W. Seifert, K. Zabrocki, E. Müller et G.J. Snyder, Thermodynamics of thermoelectric
phenomena and applications. Entropy. 13, 1481–1517 (2011)
13. J. Agar et J. Turner, Thermal diffusion in solutions of electrolytes. Proc. R. Soc. Lond. A Math.
Phys; Eng. Sci. 255, 307–330 (1960)
14. S. Di Lecce et F. Bresme, Thermal polarization of water influences the thermoelectric response
of aqueous solutions. J. Phys. Chem. B. 122, 1662–1668 (2018)