Abstract

Semiconducting organic films that are at the heart of light-emitting diodes, solar cells and transistors frequently contain a large number of morphological defects, most prominently at the interconnects between crystalline regions. These grain boundaries can dominate the overall (opto-)electronic properties of the entire device and their exact morphological and energetic nature is still under current debate. Here, we explore in detail the energetics at the grain boundaries of a novel electron conductive perylene diimide thin film. Via a combination of temperature dependent charge transport measurements and ab-initio simulations at atomistic resolution, we identify that energetic barriers at grain boundaries dominate charge transport in our system. This novel aspect of physics at the grain boundary is distinct from previously identified grain-boundary defects that had been explained by trapping of charges. We furthermore derive molecular design criteria to suppress such energetic barriers at grain boundaries in future, more efficient organic semiconductors.

Details

Title
Energy barriers at grain boundaries dominate charge carrier transport in an electron-conductive organic semiconductor
Author
Vladimirov, I 1 ; Kühn, M 2 ; Geßner, T 2 ; May, F 1 ; Weitz, R T 3 

 BASF SE, FET Systems, Ludwigshafen, Germany; InnovationLab GmbH, Heidelberg, Germany 
 BASF SE, FET Systems, Ludwigshafen, Germany 
 BASF SE, FET Systems, Ludwigshafen, Germany; InnovationLab GmbH, Heidelberg, Germany; Physics of Nanosystems, Faculty of Physics, Ludwig-Maximilians University, Munich, Germany; Center for Nanoscience (CeNS), Ludwig-Maximilians University Munich, Munich, Germany; Nanosystems Initiative Munich (NIM), Munich, Germany 
Pages
1-10
Publication year
2018
Publication date
Oct 2018
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2116607075
Copyright
© 2018. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.