A Novel Approach to Combine Scanning Electrochemical Microscopy and Scanning Photoelectrochemical Microscopy

A new instrumental technique that combines scanning electrochemical microscopy and scanning photoelectrochemical microscopy is described. This technique is capable of monitoring electroassisted and/or photoassisted reactions on semiconductor surfaces either concurrently or sequentially. The instrument uses a probe which consists of an optical fiber coated with gold and isolated from its surrounding environment with a polymer film. Measurements of the electroreduction of Br₂ at the gold ring which had been generated by photo-oxidation of Br^-on a 50 A thick TiO₂film on Ti are discussed.