Abstract
The effect of electrode-LC interface on the photogeneration process of hole in 8-PNPO12 was investigated. The photocurrent for ITO, Au, Pt electrode was found to be much higher than that for AI electrode. From photocurrent spectrum measurement, it is assumed that the hole injection from electrode is not only due to the photoelectric effect but also due to the exciton decay at interface of electrode and liquid crystal. The transient photocurrent due to delayed charge injection is observed and the rise of the photocurrent can be described by exponential function. Besides the work function of electrode materials, the possibility that the existence of shallow traps near the interface and the interaction between electrode and LC molecules also has a great effect on the hole injection process is be considered.
