Transport through Redox-Active Ru-Terpyridine Complexes Integrated in Single Nanoparticle Devices

The Journal of Physical Chemistry C, vol. 124, pp. 4881–4889

Abstract

Transition metal complexes are electrofunctional molecules due to their high conductivity and their intrinsic switching ability involving a metal-to-ligand charge transfer. Here, a method is presented to contact reliably a few to single redox-active Ru-terpyridine complexes in a CMOS compatible nanodevice and preserve their electrical functionality. Using hybrid materials from 14 nm gold nanoparticles (AuNP) and bis-{4′-[4-(mercaptophenyl)-2,2′:6′,2″-terpyridine]}-ruthenium(II) complexes a device size of 30 2 nm 2 inclusive nanoelectrodes is achieved. Moreover, this method bears the opportunity for further downscaling. The Ru-complex AuNP devices show symmetric and asymmetric current versus voltage curves with a hysteretic characteristic in two well separated conductance ranges. By theoretical approximations based on the single-channel Landauer model, the charge transport through the formed double-barrier tunnel junction is thoroughly analyzed and its sensibility to the molecule/metal contact is revealed. It can be verified that tunneling transport through the HOMO is the main transport mechanism while decoherent hopping transport is present to a minor extent.

Authors 5

1. Max Mennicken Aachen

   Forschungszentrum Jülich · Jülich Aachen Research Alliance · RWTH Aachen University

   Affiliation as printed

   Peter Grünberg Institut (PGI-7) and JARA-FIT, Forschungszentrum Jülich GmbH, Jülich 52425, Germany

   RWTH Aachen University, Aachen 52062, Germany

2. Sophia Katharina Peter Aachen JARA-FIT Institute of Inorganic Chemistry

   RWTH Aachen University

   Affiliation as printed

   JARA−FIT and Institute of Inorganic Chemistry, RWTH Aachen University, Aachen 52074, Germany

3. Corinna Kaulen corresponding Aachen Faculty of Medical Engineering and Applied Mathematics JARA-FIT Institute of Inorganic Chemistry

   RWTH Aachen University · FH Aachen

   Affiliation as printed

   Faculty of Medical Engineering and Applied Mathematics, FH Aachen, University of Applied Science, 52428 Jülich, Germany

   JARA−FIT and Institute of Inorganic Chemistry, RWTH Aachen University, Aachen 52074, Germany

4. Ulrich Simon Aachen JARA-FIT Institute of Inorganic Chemistry

   RWTH Aachen University

   Affiliation as printed

   JARA−FIT and Institute of Inorganic Chemistry, RWTH Aachen University, Aachen 52074, Germany

5. Silvia Karthäuser corresponding

   Forschungszentrum Jülich · Jülich Aachen Research Alliance

   Affiliation as printed

   Peter Grünberg Institut (PGI-7) and JARA-FIT, Forschungszentrum Jülich GmbH, Jülich 52425, Germany