Applications of the boundary element method in electrochemistry: Scanning electrochemical microscopy, part 2

Boundary element method (BEM) simulations are presented for a range of scan ning electrochemical microscopy applications. Calculations are performed to quantify the effects of the surrounding shield for a range of tip geometri es and produce three-dimensional images of electrodes embedded in substrate surfaces. Approach curves are presented for a range of experimentally expl oited probes, including the sphere-cap electrode. In addition, the BEM is u sed to generate a line scan across the interface between a conducting and n onconducting substrate for different tip geometries. The comparative resolu tion at a fixed tip-substrate separation for a microdisk and microhemispher e probe is noted. Finally, three-dimensional images of raised and recessed hemispherical electrodes embedded in nonconducting flat substrates are gene rated and the results compared to the image of a microdisk electrode.