Accuracy study on fitting procedure of kinetics SECM feedback experiments

Accuracy of kinetics characterization from SECM feedback experiments is carefully discussed. The experimental conditions that lead to the best accuracy are thus detailed on the basis on theoretical results. A recently published experimental study is also used to illustrate the discussion. Three different experimental characteristics of the SECM data acquisition are examined and discussed in this work: the geometrical characteristics of the microdisk tip, the tip-substrate distance range and the influence of an error on the zero tip-substrate distance. The best experimental conditions are encountered with the combination of results coming from approach curves with tips having Rg values larger than 10 on the 0.1–2 tip-substrate distance range and different radius, leading to a dimensionless kinetic parameter in the 0.10–1.8 range and through fit procedure with two adjustable parameters considering the zero tip-substrate distance as unknown.