CHARACTERIZATION, ADSORPTION, AND PHOTOCHEMISTRY OF SELF-ASSEMBLED MONOLAYERS OF 10-THIODECYL 2-ANTHRYL ETHER ON GOLD

The photodimerization and its photochemical reversal of the pendent an thryl groups in 10-thiodecyl 2-anthryl ether (1) as a self-assembled m onolayer on polycrystalline gold are evaluated as a photochromic surfa ce fluorescence switch. Evidence for SAM-photoresponsiveness was gathe red from surface fluorescence and surface reflectance infrared spectro scopic measurements in which changes in the monolayer were monitored b efore and after irradiation at 350 and 254 nm. Contact angle measureme nts confirmed the presence of a hydrophobic surface in the self-assemb led monolayer Au-1. Electrochemical measurements of the resulting mono layer, before and after irradiation at 350 and 254 nm, indicate that t he stable monolayers insulate the gold electrode from electrical conta ct with redox couples present in a contacting solution. These effects are interpreted by comparison with the solution phase photochemistry o f the acetyl precursor of 1.