Skip to main content

Research Repository

Advanced Search

Exploring the thermoelectric properties of oligo(phenylene-ethynylene) derivatives

Chen, Hang; Sangtarash, Sara; Li, Guopeng; Gantenbein, Markus; Cao, Wenqiang; Alqorashi, Afaf; Liu, Junyang; Zhang, Chunquan; Zhang, Yulong; Chen, Lijue; Chen, Yaorong; Olsen, Gunnar; Sadeghi, Hatef; Bryce, Martin R.; Lambert, Colin J.; Hong, Wenjing

Exploring the thermoelectric properties of oligo(phenylene-ethynylene) derivatives Thumbnail


Authors

Hang Chen

Sara Sangtarash

Guopeng Li

Markus Gantenbein

Wenqiang Cao

Afaf Alqorashi

Junyang Liu

Chunquan Zhang

Yulong Zhang

Lijue Chen

Yaorong Chen

Gunnar Olsen

Hatef Sadeghi

Colin J. Lambert

Wenjing Hong



Abstract

Seebeck coefficient measurements provide unique insights into the electronic structure of single-molecule junctions, which underpins their charge and heat transport properties. Since the Seebeck coefficient depends on the slope of the transmission function at the Fermi energy (EF), the sign of the thermoelectric voltage will be determined by the location of the molecular orbital levels relative to EF. Here we investigate thermoelectricity in molecular junctions formed from a series of oligophenylene-ethynylene (OPE) derivatives with biphenylene, naphthalene and anthracene cores and pyridyl or methylthio end-groups. Single-molecule conductance and thermoelectric voltage data were obtained using a home-built scanning tunneling microscope break junction technique. The results show that all the OPE derivatives studied here are dominated by the lowest unoccupied molecular orbital level. The Seebeck coefficients for these molecules follow the same trend as the energy derivatives of their corresponding transmission spectra around the Fermi level. The molecule terminated with pyridyl units has the largest Seebeck coefficient corresponding to the highest slope of the transmission function at EF. Density-functional-theory-based quantum transport calculations support the experimental results.

Citation

Chen, H., Sangtarash, S., Li, G., Gantenbein, M., Cao, W., Alqorashi, A., …Hong, W. (2020). Exploring the thermoelectric properties of oligo(phenylene-ethynylene) derivatives. Nanoscale, 12(28), 15150-15156. https://doi.org/10.1039/d0nr03303k

Journal Article Type Article
Acceptance Date Jun 19, 2020
Online Publication Date Jul 13, 2020
Publication Date 2020-07
Deposit Date Aug 5, 2020
Publicly Available Date Aug 5, 2020
Journal Nanoscale
Print ISSN 2040-3364
Electronic ISSN 2040-3372
Publisher Royal Society of Chemistry
Peer Reviewed Peer Reviewed
Volume 12
Issue 28
Pages 15150-15156
DOI https://doi.org/10.1039/d0nr03303k

Files








You might also like



Downloadable Citations