Talk about Carbon paste electrode

Carbon Paste Electrodes (CPE) are made from a mixture of conductive graphite powder and pasty liquid.These electrodes are simple to fabricate and provide an easily reproducible electron exchange surface.Carbon paste electrodes belong to a special group of heterogeneous carbon electrodes.These electrodes are widely used for voltammetric measurements; however, carbon paste-based sensors are also suitable for coulometric methods (amperometric and potentiometric).

Advantages 

In general, CPEs are popular because carbon pastes are readily available at minimal cost and are particularly suitable for preparing electrode materials modified with mixtures of other compounds to impart certain predetermined properties to the electrodes.Electrodes fabricated in this way are highly selective sensors for inorganic and organic electrochemistry.Electrodes modified by carbon paste, glassy carbon paste, glassy carbon,etc are called chemically modified electrodes.Chemically modified electrodes have been used to analyze inorganic and organic substances.

Disadvantages

The biggest disadvantage of CPEs limits their applicability in practical analysis, that is, success with carbon paste electrodes depends on user experience.While this is true for any type of solid electrode,CPEs are an exception. Compared with commercially available solid electrodes, the basic electrochemical properties of almost all products from each manufacturer are comparable, and each carbon paste unit is an individual, where physical, chemical and electrochemical properties may vary due to a formulation different.Therefore, each probe must be calibrated individually.While this might not be a problem in a research environment, it would be a considerable burden in a production service.