Carbon powder based films on traditional solid electrodes as an alternative to disposable electrodes

The covering of conventional solid electrode with a film using an ink containing a conductive powder and a polymer enables to broaden the potential window of the original solid electrode. A solid silver amalgam electrode covered with such a film exhibits a potential window from -600 mV to +1400 mV vs. SCE reference electrode. The renewal of the film is fast and simple: the electrode can be simply wiped with a filter paper to remove the old film and immersed into an ink solution or 1-2 mu L of this ink solution can be applied to the surface of the electrode with a micro dispenser to form a new film. Therefore, just the inexpensive film at the electrode surface is disposable and there is no need to dispose the whole, more expensive electrode. Moreover, when a suitable electrochemical pretreatment of the film electrode is applied, the same film can be used for reproducible measurements for several days.