New Approach to Electrocehmical Microtransducers Fabrication

Fabrication and electrochemical characterization of disposable working electrodes/transducers of electrochemical sensors is described in this work. The aim was to find the best electrochemical properties of screen-printed electrode substrates modified with multiwalled carbon nanotubes (MWCNTs) based active layers. Two types of platinum electrode contacts were investigated and the suitable thickness of deposited MWCNTs active layers was studied. Fabricated electrodes were characterized optically using scanning electron microscope, mechanically using profilometer and electrochemically in a standard redox couple of potassium ferro/ferricyanide employing cyclic voltammetry. The reversibility of the electrode system, size of electroactive surface area, influence of spray-coated layer thickness and platinum electrode contact size on the current response were investigated. It was found that more stable and electrochemically suitable behaviour was achieved using the electrodes with bigger platinum contact and lower thickness of deposited active layers. The electrochemical experiments also confirmed that the electroactive size of the electrode surface is at least two times larger than the designed geometrical size.