Double Doping of a Low-Ionization-Energy Polythiophene with a Molybdenum Dithiolene Complex
Journal article, 2022
Doping of organic semiconductors is crucial for tuning the charge-carrier density of conjugated polymers. The exchange of more than one electron between a monomeric dopant and an organic semiconductor allows the polaron density to be increased relative to the number of counterions that are introduced into the host matrix. Here, a molybdenum dithiolene complex with a high electron affinity of 5.5 eV is shown to accept two electrons from a polythiophene that has a low ionization energy of 4.7 eV. Double p-doping is consistent with the ability of the monoanion salt of the molybdenum dithiolene complex to dope the polymer. The transfer of two electrons to the neutral dopant was also confirmed by electron paramagnetic resonance spectroscopy since the monoanion, but not the dianion, of the molybdenum dithiolene complex features an unpaired electron. Double doping allowed an ionization efficiency of 200% to be reached, which facilitates the design of strongly doped semiconductors while lessening any counterion-induced disruption of the nanostructure.
Author
Emmy Järsvall
Chalmers, Chemistry and Chemical Engineering, Applied Chemistry
Till Biskup
Universität des Saarlandes
Yadong Zhang
Georgia Institute of Technology
University of Colorado
Renee Kroon
Linköping University
Chalmers, Chemistry and Chemical Engineering, Applied Chemistry
Stephen Barlow
University of Colorado
Georgia Institute of Technology
Seth R. Marder
Ctr Organ Photon & Elect
University of Colorado at Boulder
Georgia Institute of Technology
Christian Müller
Chalmers, Chemistry and Chemical Engineering, Applied Chemistry
Chemistry of Materials
0897-4756 (ISSN) 1520-5002 (eISSN)
Vol. 34 12 5673-5679Subject Categories
Chemical Engineering
Materials Chemistry
DOI
10.1021/acs.chemmater.2c01040
PubMed
35782206