Thermoelectric properties of oligoglycine molecular wires

Hou, S. and Wu, Q. and Sadeghi, H. and Lambert, C.J. (2019) Thermoelectric properties of oligoglycine molecular wires. Nanoscale, 11 (8). pp. 3567-3573. ISSN 2040-3364

Full text not available from this repository.

Abstract

We have investigated the electrical and thermoelectrical properties of glycine chains with and without cysteine terminal groups. The electrical conductance of (Gly) n , (Gly) n Cys and Cys(Gly) n Cys molecules (where Gly, Cys represent glycine and cysteine and n = 1-3) was found to decay exponentially with length l as e -βl . Our results show that connecting the molecules to gold electrodes via the sulphur atom of the cysteine moiety leads to higher β factors of 1.57 Å -1 and 1.22 Å -1 for (Gly) n Cys and Cys(Gly) n Cys respectively, while β = 0.92 Å -1 for (Gly) n . We also find that replacing the peptide bond with a methylene group (-CH 2 -) increases the conductance of (Gly) 3 Cys. Furthermore, we find the (Gly) 1 Cys and Cys(Gly) 1 Cys systems show good thermoelectrical performance, because of their high Seebeck coefficients (∼0.2 mV K -1 ) induced by the sulphur of the cysteine(s). With the contributions of both electrons and phonons taken into consideration, a high figure of merit ZT = 0.8 is obtained for (Gly) 1 Cys at room temperature, which increases further with increasing temperature, suggesting that peptide-based SAM junctions are promising candidates for thermoelectric energy harvesting.

Item Type: Journal Article
Journal or Publication Title: Nanoscale
Uncontrolled Keywords: /dk/atira/pure/subjectarea/asjc/2500
Subjects:
Departments: Faculty of Science and Technology > Physics
ID Code: 131822
Deposited By: ep_importer_pure
Deposited On: 02 Apr 2019 12:05
Refereed?: Yes
Published?: Published
Last Modified: 21 Feb 2020 04:43
URI: https://eprints.lancs.ac.uk/id/eprint/131822

Actions (login required)

View Item View Item