N-Type Organic Thermoelectrics Improved Power Factor by Tailoring Host-Dopant Miscibility

N-Type Organic Thermoelectrics : Improved Power Factor by Tailoring Host-Dopant Miscibility

© 2017 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bibliographische Detailangaben
Veröffentlicht in:Advanced materials (Deerfield Beach, Fla.). - 1998. - 29(2017), 36 vom: 01. Sept.
1. Verfasser: Liu, Jian (VerfasserIn)
Weitere Verfasser: Qiu, Li, Portale, Giuseppe, Koopmans, Marten, Ten Brink, Gert, Hummelen, Jan C, Koster, L Jan Anton
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2017
Zugriff auf das übergeordnete Werk:Advanced materials (Deerfield Beach, Fla.)
Schlagworte:Journal Article conductivity fullerene derivatives n-type doping organic thermoelectrics
Beschreibung
Zusammenfassung:© 2017 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
In this contribution, for the first time, the polarity of fullerene derivatives is tailored to enhance the miscibility between the host and dopant molecules. A fullerene derivative with a hydrophilic triethylene glycol type side chain (PTEG-1) is used as the host and (4-(1,3-dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)phenyl)dimethylamine n-DMBI) as the dopant. Thereby, the doping efficiency can be greatly improved to around 18% (<1% for a nonpolar reference sample) with optimized electrical conductivity of 2.05 S cm-1 , which represents the best result for solution-processed fullerene derivatives. An in-depth microstructural study indicates that the PTEG-1 molecules readily form layered structures parallel to the substrate after solution processing. The fullerene cage plane is alternated by the triethylene glycol side chain plane; the n-DMBI dopants are mainly incorporated in the side chain plane without disturbing the π-π packing of PTEG-1. This new microstructure, which is rarely observed for codeposited thin films from solution, formed by PTEG-1 and n-DMBI molecules explains the increased miscibility of the host/dopant system at a nanoscale level and the high electrical conductivity. Finally, a power factor of 16.7 µW m-1 K-2 is achieved at 40% dopant concentration. This work introduces a new strategy for improving the conductivity of solution-processed n-type organic thermoelectrics
Beschreibung:Date Completed 18.07.2018
Date Revised 01.10.2020
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1521-4095
DOI:10.1002/adma.201701641