Tuning the thermoelectric properties of metallo-porphyrins

Al-Galiby, Qusiy and Sadeghi, Hatef and Algharagholy, Laith and Grace, Iain Mark and Lambert, Colin John (2016) Tuning the thermoelectric properties of metallo-porphyrins. Nanoscale, 2016 (4). pp. 2428-2433. ISSN 2040-3364

[thumbnail of c5nr06966a]
Preview
PDF (c5nr06966a)
c5nr06966a.pdf - Published Version
Available under License Creative Commons Attribution.

Download (1MB)

Abstract

We investigated the thermoelectric properties of metalloporphyrins connected by thiol anchor groups to gold electrodes. By varying the transition metal-centre over the family Mn, Co, Ni, Cu, Fe, and Zn we are able to tune the molecular energy levels relative to the Fermi energy of the electrodes. The resulting single-molecule room-temperature thermopowers range from almost zero for Co and Cu centres, to +80 μV K−1 and +230 μV K−1 for Ni and Zn respectively. In contrast, the thermopowers with Mn(II) or Fe(II) metal centres are negative and lie in the range −280 to −260 μV K−1. Complexing these with a counter anion to form Fe(III) and Mn(III) changes both the sign and magnitude of their thermopowers to +218 and +95 respectively. The room-temperature power factors of Mn(II), Mn(III), Fe(III), Zn and Fe(II) porphyrins are predicted to be 5.9 × 10−5 W m−1 K−2, 5.4 × 10−4 W m−1 K−2, 9.5 × 10−4 W m−1 K−2, 1.6 × 10−4 W m−1 K−2 and 2.3 × 10−4 W m−1 K−2 respectively, which makes these attractive materials for molecular-scale thermoelectric devices.

Item Type:
Journal Article
Journal or Publication Title:
Nanoscale
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/2500
Subjects:
?? materials science(all) ??
ID Code:
77784
Deposited By:
Deposited On:
20 Jan 2016 16:08
Refereed?:
Yes
Published?:
Published
Last Modified:
18 Dec 2023 01:33