Methylnaphthalene as a Fluorescent Probe in Ionic, Nonionic, Reverse Micelles and Photogalvanic Effect

The absorption spectrum of I Methylnaphthalene (1 MN) is not perturbed in the presence of halides and surfactants studied (cetyl trimethyl ammonium bromide, CTAB, sodium dodeeyl sulphate, SDS and octyl phenyl polyoxyethylene ether, Triton X-100), indicating no molecular interaction between surfactants, halides and 1 MN in the ground state. The fluorescence of 1 MN is quenched in the presence of halides. The quenching process is affected in the presence of normal micelles and reverse micelles (RM) of Triton X-100 in chloroform. The quenching results have been processed in the light of Stern Volmer equation and its modified form to evaluate the extent of interaction between the fluorophore and the quencher. The magnitude of the Stern Volmer constant (K_sv) in quenching follows the trend I^- > Br^- > Cl^- in all micelles and for each ion the trend in the terms of the surfactants is CTAB > Triton X-100 > SDS > RM. In RM, the Stern Volmer quenching constant increases with ω ([H₂0]/[Triton X-1001). Statistical models describing the distribution of solubilized molecules in Triton X-100 reverse micelles are used to explain the results. The photogalvanic effect of 1 MN-Surfactant system has been studied using platinum electrode and redox electrode. Photovoltage is generated only with CTAB and not with other surfactants studied.