Protonation-deprotonation effects on the electrooptics of bipyridine containing PPV derivatives

The electrooptic properties of novel bipyridine-containing PPV derivatives were found to be sensitive to the presence of sub-ppm concentration of different acids and bases. Upon exposure to ammonia (or HCl) vapors, the polymer film turns yellow (orange) and the electro- and photoluminescence peak at 580 (640) nm. Using controlled exposure, stable yellow/orange luminescent devices could be fabricated. In addition, reversible decrease (increase) of the effect of aggregation is observed in the electro- and photoinduced absorption, upon the deprotonation (protonation) process.