Determination of microscopic electrode kinetics with electrogenerated chemiluminescence imaging

Abstract

Abstract Light produced by the electrogenerated chemiluminescence reaction of luminol in alkaline peroxide was monitored with a sensitive imaging system. The light images were taken to represent the level of microscopically local activity on the electrode surface with a spatial resolution in the submicrometer domain. The temporal resolving capabilities of the imaging system permitted the construction of time‐sequenced images and intensity‐potential profiles, the latter being equivalent to a microscopically local voltammogram. Spatial variation in luminol oxidation kinetics were observed at porphyrin‐coated glassy carbon, carbon paste, and anodized glassy carbon electrodes. Implications for other composites and microelectrodes are discussed.