Resonant Transport in Single Diketopyrrolopyrrole Junctions
Author(s):
Yaping Zang, Suman Ray, E-Dean Fung, Anders Borges, Marc H. Garner, Michael L. Steigerwald, Gemma C. Solomon, Satish Patil, Latha Venkataraman
Journal:
Journal of the American Chemical Society
Year:
2018
Volume:
140
Pages
13167–13170
DOI:
10.1021/jacs.8b06964
Abstract:
We study the single-molecule transport properties of small bandgap diketopyrrolopyrrole oligomers (DPPn, n = 1−4) with lengths varying from 1 to 5 nm. At a low bias voltage, the conductance decays exponentially as a function of length indicative of nonresonant transport. However, at a high bias voltage, we observe a remarkably high conductance close to 10−2 G0 with currents reaching over 0.1 μA across all four oligomers. These unique transport properties, together with density functional theory-based transport calculations, suggest a mechanism of resonant transport across the highly delocalized DPP backbones in the high bias regime. This study thus demonstrates the unique properties of diketopyrrolopyrrole derivatives in achieving highly efficient long-range charge transport in singlemolecule devices