Molecular rectifier composed of DNA with high rectification ratio enabled by intercalation.
The predictability, diversity and programmability of DNA make it a leading candidate for the design of functional electronic devices that use single molecules, yet its electron transport properties have not been fully elucidated. This is primarily because of a poor understanding of how the structure of DNA determines its electron transport. Here, we demonstrate a DNA-based molecular rectifier constructed by site-specific intercalation of small molecules (coralyne) into a custom-designed 11-base-pair DNA duplex. Measured current-voltage curves of the DNA-coralyne molecular junction show unexpectedly large rectification with a rectification ratio of about 15 at 1.1 V, a counter-intuitive finding considering the seemingly symmetrical molecular structure of the junction. A non-equilibrium Green's function-based model-parameterized by density functional theory calculations-revealed that the coralyne-induced spatial asymmetry in the electron state distribution caused the observed rectification. This inherent asymmetry leads to changes in the coupling of the molecular HOMO-1 level to the electrodes when an external voltage is applied, resulting in an asymmetric change in transmission.
Single Molecule Study Laboratory, College of Engineering and Nanoscale Science and Engineering Center, University of Georgia, Athens, Georgia 30602, USA.
Cunlan
C
Guo
Single Molecule Study Laboratory, College of Engineering and Nanoscale Science and Engineering Center, University of Georgia, Athens, Georgia 30602, USA.
Kun
K
Wang
Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
Elinor
E
Zerah-Harush
Single Molecule Study Laboratory, College of Engineering and Nanoscale Science and Engineering Center, University of Georgia, Athens, Georgia 30602, USA.
Joseph
J
Hamill
Single Molecule Study Laboratory, College of Engineering and Nanoscale Science and Engineering Center, University of Georgia, Athens, Georgia 30602, USA.
Bin
B
Wang
Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.|Ilse-Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
Yonatan
Y
Dubi
Single Molecule Study Laboratory, College of Engineering and Nanoscale Science and Engineering Center, University of Georgia, Athens, Georgia 30602, USA.
Bingqian
B
Xu
D001483:Base Sequence; D001600:Berberine Alkaloids / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D004553:Electric Conductivity; D055615:Electrical Equipment and Supplies; D004566:Electrodes; D004581:Electronics; D007364:Intercalating Agents / Q000737:chemistry*; D011789:Quantum Theory
D001600:Berberine Alkaloids; D007364:Intercalating Agents; C000666:coralyne; D004247:DNA