A simulation model was developed to investigate the proton generation and diffusion from the protonator IDEs, using FEA by COMSOL Multiphysics 5.5 software, following the galvanostatic model presented in our previous work (O . The geometry of the model consisted of 3 mm square box, which acted as the experimental domain and incorporated with two sets of interdigitated 1 µm wide and 150 nm high microband electrodes (20 protonator electrodes and 20 sensing electrodes), with a gap of 1 µm between them. A flux of proton was initiated on the protonators surface by enforcing a steady anodic current. It was hypothesized that this flux would be directly proportional to the current applied at the electrodes: