Scanning electrochemical microscopy: approach curves for sphere-cap scanning electrochemical microscopy tips.

The parameters of functions used to predict diffusion-controlled scanning electrochemical microscopy approach curves under positive and negative (hindered diffusion) feedback for sphere-cap tips are reported. These functions were obtained by fitting approach curves simulated with an error-bounded adaptive finite element algorithm. Several geometries corresponding to different sphere-cap dimensions were considered including the effect of the tip insulating sheath.