Can a helical molecule be an efficient functional element to meet the present requirement of thermoelectric efficiency?

¹ Department of Physics, Adamas University - Adamas Knowledge City, Barasat-Barrackpore Road, 24 Parganas North, Kolkata-700 126, India
² Physics and Applied Mathematics Unit, Indian Statistical Institute - 203 Barrackpore Trunk Road, Kolkata-700 108, India

^(a) santanu.maiti@isical.ac.in

Received: 12 December 2018
Accepted: 23 April 2019

Abstract

Although a large amount of works has been done to test whether molecular junctions can offer suitable energy conversion from heat energy to electrical energy, still it is questionable mainly because of their too poor efficiencies. Here we report that a single helical molecule subjected to transverse electric field exhibits efficient thermoelectric energy conversion. The structural geometry has a significant effect on electronic transmission, and thus, thermopower and figure of merit (FOM), namely, ZT, which we verify by comparing the results of single-stranded DNA (ssDNA) and α-helical protein molecules. We prove that α-helical protein is much superior than ssDNA, and our analysis provides a boost in the field of energy conversion. Finally, we examine the role of the electric field which could be another eminent parameter for controlling the efficiency.