Long-Lived, Highly Soluble Pentacene Derivatives for Organic Molecular Electronics
NSF Grant Number: EEC-0425826
PI(s): G. Miller, M. Dokmeci, N. McGruer
Student and Post-doctoral Researchers: I. Kaur, R. Kopreski, W. Jia, S. Selvarasah
Institutions: University of New Hampshire & Northeastern University
Objective: The goals of the research were to prepare soluble, persistent pentacene derivatives that resist photo-oxidation.
Broader Impact: Our results have significant implications for the field of organic molecular electronics. Soluble, persistent alkylthio- and arylthiopentacenes represent promising, new candidates for thin-film OFET, OLED and organic photo-voltaic (OPV) devices.
Significant Results: We completed a combined experimental and computational study of a series of substituted pentacenes included halogenated, phenylated, silylethynylated and thiolated derivatives. Experimental studies included the synthesis and characterization of both new and known pentacene derivatives and a kinetic study of each derivative under photo-oxidative conditions. Computationally, we calculated the energies of the frontier orbitals of each pentacene derivative at the B3LYP/6-311+G**//PM3 level in order to correlate HOMO and LUMO energies with measured half-lives. The results provide for the first time a quantitative assessment of the photo-oxidative stability of a series of pentacene derivatives as a function of substituents. Most interesting is that alkylthio- and arylthiopentacene derivatives, simple to prepare but previously little studied, are considerably more resistant to photo-oxidation than all other pentacene derivatives known.