title: Gradients of Rectification: Tuning Molecular Electronic Devices by the Controlled Use of Different-Sized Diluents in Heterogeneous Self-Assembled Monolayers.
abstract: Molecular electronics has received significant attention in the last decades. To hone performance of devices, eliminating structural defects in molecular components inside devices is usually needed. We herein demonstrate this problem can be turned into a strength for modulating the performance of devices. We show the systematic dilution of a monolayer of an organic rectifier (2,2'-bipyridine-terminated n-undecanethiolate) with electronically inactive diluents (n-alkanethiolates of different lengths), gives remarkable gradients of rectification. Rectification is finely tunable in a range of approximately two orders of magnitude, retaining its polarity. Trends of rectification against the length of the diluent indicate the gradient of rectification is extremely sensitive to the molecular structure of the diluent. Further studies reveal that noncovalent intermolecular interactions within monolayers likely leads to gradients of structural defect and rectification.
authors.affiliation: Department of Chemistry, Korea University, Seoul, 136-701, Korea.
authors.forename: Gyu Don
authors.initials: GD
authors.lastname: Kong
authors.affiliation: Department of Chemistry, Korea University, Seoul, 136-701, Korea.
authors.forename: Miso
authors.initials: M
authors.lastname: Kim
authors.affiliation: Department of Chemistry, Korea University, Seoul, 136-701, Korea.
authors.forename: Soo Jin
authors.initials: SJ
authors.lastname: Cho
authors.affiliation: Department of Chemistry, Korea University, Seoul, 136-701, Korea. hyoon@korea.ac.kr.
authors.forename: Hyo Jae
authors.initials: HJ
authors.lastname: Yoon
keywords: EGaIn junctions; dilution effects; molecular electronics; rectifiers; self-assembled monolayers