The 3DPEC reasonably reproduces the studied [Fe(CN)6] 4-/3-probe kinetics. The process is considered irreversible, with kinetics somewhat limited by the intrinsic nature of the CB-PLA composites, introducing an iR drop. Moreover, the XRM studies revealed that the CB-PLA/PLA interface is sharp and does not affect ESA reproducibility. 3DPEC activation by electrochemical saponification in 1 M NaOH under CV cycling effectively increased the ESA, which is nearly equal to the geometric surface area of the WE within 3DPEC. It was also testified that the proposed activation protocol modifies both WE and CE simultaneously.