Abstract
Monolayer polyimide films containing azobenzene were prepared on SnO2- coated glass substrates by using the Langmuir-Blodgett technique. We have examined the electrical properties of precursor films of polyimide (AZBPAA) and polyimide films (AZBPI). The displacement current due to trans-cis photoisomerization was generated by alternate irradiation with UV light and visible light in AZBPAA LB films. In contrast, the displacement current was not generated in AZBPI LB films, because the photoisomerization was not initiated and the transportation of photoexcited electrons in the films was negligibly small.
The displacement current due to the photoexcited electron transfer between AZBPAA monolayers and electrodes was found to be generated only in the initial photoirradiation by introducing an electrically insulating film (PIBM LB films) between AZBPAA monolayers and electrodes. It was concluded that motion of charged particles can be purposefully controlled and be detected by the displacement current measurement.
