Photoassistcd Anodic Oxidation of Bromide on an n-Type Titanium Dioxide Electrode in an Amide-type Ionic Liquid

摘要

Photoassisted anodic oxidation of bromide (Br~-) on an n-type titanium dioxide (n-TiO_2) electrode has been investigated in an amide-type ionic liquid, 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide (BMPTFSA) containing BMPBr at various concentrations. Photoassisted anodic oxidation of BMPTFSA was confirmed in the absence of BMPBr. A photoanodic current corresponding to the oxidation of Br" was observed under illumination of UV light. The onset potential of the photoanodic current was the function of the concentration of Br", suggesting the flat band potential of the n-TiO_2 electrode in the ionic liquid is related to the potential of zero charge, which is expected to be affected by the specific adsorption of Br" on the n-TiO_2 electrode.