Poster Sessions

2024 KPS Spring Meeting

Wednesday-Friday, November 4-6, 2020; Virtual Conference
Session P1-ap.4: Organic electronics and photonics
1:00 PM-1:50 PM, Thursday, November 05, 2020
Abstract: P1-ap.413* : Highly Tunable Molecular Rectifier Realized by Interfacial Design in Molecular Heterojunction with Two-Dimensional Materials
Shin Jaeho
(KU-KIST Graduate School of Converging Science and Technology, Korea University)

SHIN Jaeho 1, YANG Seunghoon 1, JANG Yeonsik 2, EO Jung Sun 1, KIM Tae-Wook 3, LEE Takhee 2, LEE Chul-Ho 1, WANG Gunuk *1
(1KU-KIST Graduate School of Converging Science and Technology, Korea University, 2Department of Physics and Astronomy, and Institute of Applied Physics, Seoul National University, 3Department of Flexible and Printable Electronics, Jeonbuk National University)
Until now, a specifically designed functional molecular species has been recognized as an absolute necessity for realizing the diode’s behavior in molecular electronic junctions.[1-4] However, even non-functional molecules can be served for the implementation of molecular diode with employing appropriate energy band alignment in heterostructure molecular junctions. Here, we suggest a facile approach for the implementation of a tailored diode in a molecular junction based on non-functionalized alkyl and conjugated molecular monolayers.[5] A two-dimensional (2D) semiconductor (MoS2 and WSe2) was used as a rectifying designer at the alkyl or conjugated molecule/Au interface. From the adjustment of band alignment at molecules/2D semiconductor interface that can activate different transport pathways depending on the voltage polarity, the rectifying characteristics can be implemented and controlled. To demonstrate the molecular tunneling in positive bias region and Schottky emission in negative bias region, we performed temperature-dependent measurements of the solid-state devices composed of Gr/NL-MoS2/OPT2/Au junctions. The rectification ratio could be widely tuned from 1.24 to 1.83 × 104 by changing the molecular species and type and the number of layers of the 2D semiconductors in the heterostructure molecular junction. Our work sets a design rule for implementing tailored-diode function in a molecular heterojunction structure with non-functionalized molecular systems.

[1] Díez-Pérez, I. et al. Rectification and stability of a single molecular diode with controlled orientation. Nat. Chem. 1, 635 (2009).
[2] Van Dyck, C. & Ratner, M. A. Molecular rectifiers: a new design based on asymmetric anchoring moieties. Nano Lett. 15, 1577-1584 (2015).
[3] Yuan, L., Breuer, R., Jiang, L., Schmittel, M. & Nijhuis, C. A. A molecular diode with a statistically robust rectification ratio of three orders of magnitude. Nano Lett. 15, 5506-5512 (2015).
[4] Chen, X. et al. Molecular diodes with rectification ratios exceeding 105 driven by electrostatic interactions. Nat. Nanotechnol. 12, 797 (2017).
[5] Shin, J. et al. Tunable rectification in a molecular heterojunction with two-dimensional semiconductors. Nat. Commun. 11, 1412 (2020).

Molecular electronics, 2D semiconductors, Molecular heterojunction, Molecular-Scale Rectifier