Last Updated:

21/08/2020 - 14:35

The research article “The Role of Electrostatic Interaction between Free Charge Carriers and Counterions in Thermoelectric Power Factor of Conducting Polymers: From Crystalline to Polycrystalline Domains”, co-authored by METU member Asst. Prof. Erol Yıldırım, has been published in Advanced Theory and Simulations.

One of the most burning problems in organic thermoelectrics is the lack of deep understanding on the key limiting factors of thermoelectric efficiency at different length scales for conducting polymers. Here, by examining a prototypical π-conjugated polymer, poly(3-hexylthiophene) from molecular level to crystalline and polycrystalline domains, and on the basis of first-principles calculations, new insights are presented into the thermoelectric transport in conducting polymers, and new material design guidelines are provided. It is proved that in the crystalline domains of conducting polymers, due to the strong electrostatic interactions between free charge carriers and counterions, the power factor within a wide range of doping level is governed by the counterion-induced electronic scattering. It is corroborated that in the polycrystalline domains, although the short mean free path prevents the holes undergoing grain-boundary scatterings, the crystallite orientations relative to the conduction path and the grain sizes strongly affect the power factor, leading to the modulation of the power factor by at least two orders of magnitude.


Shi, W., Yildirim, E., Wu, G., Wong, Z.M., Deng, T., Wang, J.‐S., Xu, J. and Yang, S.‐W. (2020). The role of electrostatic interaction between free charge carriers and counterions in thermoelectric power factor of conducting polymers: From crystalline to polycrystalline domains. Advanced Theory and Simulations, 3(6) doi:10.1002/adts.202000015

 

Article access: https://onlinelibrary.wiley.com/doi/full/10.1002/adts.202000015


METU Author

Asst. Prof. Erol Yıldırım

erolyil@metu.edu.tr Scopus Author ID: 16403972600
About the author ORCID: 0000-0002-9989-9882

Tags/Keywords:

conducting polymers, first-principles calculations, power factor, thermoelectrics


Other authors:
Shi, W., Wu, G., Wong, Z.M., Deng, T., Wang, J.-S., Xu, J., & Yang, S.-W.


Acknowledgment:
This work was supported by the Agency for Science, Technology and Research (A*STAR) of Singapore (1527200024 and 1527200019). Computational resources were provided by the National Supercomputing Centre Singapore (NSCC) and A*STAR Computational Resource Centre (A*CRC).