Electrochemical deposition of Prussian Blue films across interdigital array electrodes and their use in gas sensing

Prussian Blue films were deposited across carbon ink array electrodes and solid-state voltammetry was performed. The current measured from the array, when the potential across the two electrode array was + 0.5 V, was found to be dependent upon the nature of the bathing gas. It was seen that methanol, water vapor and dichloroethane lead to an increase in the measured current. Upon switching between nitrogen and the aforementioned gases the responses obtained were reversible and rapid, with a response time in the order of 5 s. It is concluded that the bathing gas does not act as an oxidant or reductant but it helps to solvate the internal counterionic species, and leads to an increase in mobility.