Scale-up of room-temperature constructive quantum interference from single molecules to self-assembled molecular-electronic films
File(s)
Accepted version
Supporting information
Author(s)
Type
Journal Article
Abstract
The realization of self-assembled molecular-electronic films, whose room-temperature transport properties are controlled by quantum interference (QI), is an essential step in the scale-up of QI effects from single molecules to parallel arrays of molecules. Recently, the effect of destructive QI (DQI) on the electrical conductance of self-assembled monolayers (SAMs) has been investigated. Here, through a combined experimental and theoretical investigation, we demonstrate chemical control of different forms of constructive QI (CQI) in cross-plane transport through SAMs and assess its influence on cross-plane thermoelectricity in SAMs. It is known that the electrical conductance of single molecules can be controlled in a deterministic manner, by chemically varying their connectivity to external electrodes. Here, by employing synthetic methodologies to vary the connectivity of terminal anchor groups around aromatic anthracene cores, and by forming SAMs of the resulting molecules, we clearly demonstrate that this signature of CQI can be translated into SAM-on-gold molecular films. We show that the conductance of vertical molecular junctions formed from anthracene-based molecules with two different connectivities differ by a factor of approximately 16, in agreement with theoretical predictions for their conductance ratio based on CQI effects within the core. We also demonstrate that for molecules with thioether anchor groups, the Seebeck coefficient of such films is connectivity dependent and with an appropriate choice of connectivity can be boosted by ∼50%. This demonstration of QI and its influence on thermoelectricity in SAMs represents a critical step toward functional ultra-thin-film devices for future thermoelectric and molecular-scale electronics applications.
Date Issued
2020-05-04
Date Acceptance
2020-04-26
Citation
Journal of the American Chemical Society, 2020, 142 (19), pp.8555-8560
ISSN
0002-7863
Publisher
American Chemical Society
Start Page
8555
End Page
8560
Journal / Book Title
Journal of the American Chemical Society
Volume
142
Issue
19
Copyright Statement
© 2020 American Chemical Society. This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of the American Chemical Society, after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/jacs.9b13578
Sponsor
Engineering & Physical Science Research Council (E
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/32343894
Grant Number
EP/N032977/1
Subjects
Science & Technology
Physical Sciences
Chemistry, Multidisciplinary
Chemistry
ORBITAL VIEWS
FUNCTIONALIZED FULLERENES
TUNNELING JUNCTIONS
CONDUCTANCE
TRANSPORT
THERMOPOWER
MONOLAYERS
SURFACES
AU(111)
POLYMER
General Chemistry
03 Chemical Sciences
Publication Status
Published online
Coverage Spatial
United States
Date Publish Online
2020-04-28