We thank the National Science Foundation (DMR-0408589) and the New Jersey Center for Organic Optoelectronics for funding support. The work at Georgia Tech was partly supported by the National Science Foundation (under the STC program award DMR-0120967 and grant CHE-0342321) and the Georgia Tech “Center for Organic Photonics and Electronics”. Helpful discussions with Prof. J. Schwartz are gratefully acknowledged.
Molecular n-Type Doping of 1,4,5,8-Naphthalene Tetracarboxylic Dianhydride by Pyronin B Studied Using Direct and Inverse Photoelectron Spectroscopies†
Article first published online: 16 FEB 2006
Copyright © 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Advanced Functional Materials
Volume 16, Issue 6, pages 831–837, April, 2006
How to Cite
Chan, C. K., Kim, E.-G., Brédas, J.-L. and Kahn, A. (2006), Molecular n-Type Doping of 1,4,5,8-Naphthalene Tetracarboxylic Dianhydride by Pyronin B Studied Using Direct and Inverse Photoelectron Spectroscopies. Adv. Funct. Mater., 16: 831–837. doi: 10.1002/adfm.200500402
- Issue published online: 30 MAR 2006
- Article first published online: 16 FEB 2006
- Manuscript Accepted: 6 SEP 2005
- Manuscript Received: 29 JUN 2005
- Organic semiconductors;
Molecular n-type doping of 1,4,5,8-naphthalene tetracarboxylic dianhydride (NTCDA) by pyronin B (PyB) is investigated using ultraviolet photoelectron spectroscopy (UPS), inverse photoelectron spectroscopy (IPES), and current–voltage (I–V) measurements. Deposition of small amounts (< 2 Å) of PyB on pristine NTCDA films leads to a shift of all the molecular levels away from the Fermi level by nearly 0.20 eV, indicative of n-type doping of NTCDA by PyB. Interface and bulk energy levels of films formed by co-evaporation of host and dopant show similarly efficient n-doping. The spectroscopic measurements are confirmed by I–V measurements, which show a four-orders-of-magnitude increase in current in doped films. The comparison of data obtained from UPS of the neat PyB film with the results of density functional theory calculations confirm that two species of PyB are evaporated and condensed into the solid state, with one species primarily responsible for doping.