Potentiostats are control and measurement devices designed to output a controlled potential. Unlike other voltage sources, potentiostats contain feedback circuitry between the output and measured potential. This enables them to maintain a set potential through a circuit with varying resistance by increasing or decreasing the output, ensuring that the measured potential remains constant as per Ohm's Law.
Potentiostatic experiments such as cyclic voltammetry use a three electrode system consisting of a working electrode, a counter electrode, and a reference electrode. These are placed in an electrochemical cell containing the electrolyte solution and a reference solution. During a measurement, the potential of the reference electrode remains fixed while the potentiostat varies the potential of the working electrode. The counter electrode completes the circuit and allows current to flow, counteracting the redox events taking place at the working electrode due to electrochemical reactions in the cell, and ensuring that no current passes between the reference and working electrodes.
Screw-fit PTFE lid with 3-electrode holes and 2-gas holes.
Highly polished platinum embedded in polytetrafluoroethylene (PTFE) plastic bodies.
All dimensions are in millimetres.