Fluorescence and Transient Absorption Spectra of Solid Surface: Development of Time-Resolved Total Internal Reflection Spectroscopy

This chapter discusses two time-resolved spectroscopic methods, giving direct information on picosecond and nanosecond photodynamics of solid surface. One is a fluorescence spectroscopy that analyzes fluorescence behavior of the surface area excited by the evanescent laser pulse. The other is to get transient ultraviolet—visible absorption spectra by using the evanescent light as a probe beam. The chapter describes depth-distribution of fluorescent dopants in cast polymer film. Fluorescence spectra of poly(N-vinylcarbazole) film doped with perylene are shown. They consist of two broad structureless excimer bands of the polymer with a shoulder at 375nm and a peak at 420nm, and perylene band with a vibrational structure above 450nm. It is worth noting that the perylene fluorescence intensity under the total internal reflection condition is relatively weaker than that under the normal one. As the boundary surface is selectively excited under the former condition, the structure near the surface should be different from the bulk. It is well known that the excitation energy migrates over carbazolyl chromophores and is trapped in the doped perylene efficiently.