Evanescent wave induced fluorescence spectroscopy and time-correlated single-photon counting have been combined to provide a method of studying the fluorescence decay profiles of fluorophores at a solid/solution interface. Using these techniques the photophysical properties of tetrasulphonated aluminium phthalocyanine (AlS4Pc) in methanol and water solution have been studied at a fused silica interface. In a poor solvent, such as methanol, AlS4Pc is shown to form an adsorbed monolayer on the fused silica surface and exhibit a fluorescence decay profile that deviates from the simple, first-order, single-exponential kinetics of the bulk solution. By changing the solvent to water, which is a good solvent for AlS4Pc, the surface/bulk differences are not observed. The ability of time-resolved fluorescence spectroscopy to distinguish between concentration and quantum-yield effects on evanescent wave induced fluorescence intensity, is clearly demonstrated.
|Number of pages||6|
|Journal||Journal of the Chemical Society - Faraday Transactions|
|Publication status||Published - 1991|
ASJC Scopus subject areas
- Physical and Theoretical Chemistry