Electrochemical deposition of a pyrrole-1-yl substituted perylene diimide for photoluminescence and electrochromism

N,N'-Bis(3-pyrrol-1-yl-propyl)-1,6,7,12-tetrakis(4-tert-butylphenoxy) perylene-3,4,9,10-tetracarboxylic acid diimide (PDI-2Py) was synthesized by imidization of 3-pyrrol-1-yl-propylamine and 1,6,7,12-tetrakis(4-tert-butylphenoxy) perylene-3,4,9,10-tetracarboxylic acid dianhydride. PDI-2Py could be electrodeposited by scanning the potential between 0 and 1.2 V vs. Ag/Ag+ in a potentiodynamic mode to form a red film stably adhering to a glassy carbon or indium tin oxide electrodes which was insoluble in common organic solvents. Considering that PDI without pyrrole moiety could not be electrodeposited in the same potential range and that the pyrrole moiety can be electropolymerized at above ca. 0.9 V vs. Ag/Ag+, we conclude that PDI-2Py was electropolymerized to form the corresponding polymer [P(PDI-2Py)]. The resulting P(PDI-2Py) exhibited photoluminescence (lambda(max):629 nm) upon photoexcitation at 573 nm. From the electrochromic study, P(PDI-2Py) turned red (lambda(max):573 nm) and emerald (lambda(max):788 nm) at 0 and 21.8 V vs. Ag/Ag+, respectively. P(PDI-2Py) film formation by electrodeposition of PDI-2Py is one of the promising methods for multilayer fabrications because the insoluble characteristics of the resulting film in common organic solvents allows variety in the choice of solvents for the coating of an upper layer. (C) 2004 The Electrochemical Society.