How does a Galvanostat work?
As a galvanostat, the instrument controls the cell current rather than the cell voltage. The working electrode could be a metal on which a reaction takes place or – in corrosion measurements – a sample of the corroded material. For testing batteries, the potentiostat is connected directly to the battery electrodes.
How does a potentiostat work?
A potentiostat (Figure 1) is an electronic instrument that controls the voltage difference between a Working Electrode and a Reference Electrode. The potentiostat implements this control by injecting current into the cell through an Auxiliary, or Counter, electrode.
How does a three electrode cell work?
The three electrode system consists of a working electrode, counter electrode, and reference electrode. The reference electrode’s role is to act as a reference in measuring and controlling the working electrode potential, without passing any current.
What does a counter electrode do?
The counter or auxiliary electrode provides a means of applying input potential to the working electrode. The purpose of these electrodes is to complete the circuit and allow charge to flow.
Why do we use 3 electrode system?
For a better control and measurement of the current and potential going through the cell during the electricity driven chemical reaction, it is better to use a three electrode system to reduce and compensate the potential changes caused by large currents passing through the working and counter electrodes.
What is a 3 electrode system?
Why are counter electrodes used?
The counter electrode (also known as auxiliary electrode), is an electrode which is used to close the current circuit in the electrochemical cell. It is usually made of an inert material (e.g. Pt, Au, graphite, glassy carbon) and usually it does not participate in the electrochemical reaction.