Abstract:
This paper describes a GaNFET-based high-speed
charge injection circuit to study fast redox processes at electrodeelectrolyte
interfaces. The circuit allows the rates of electrode
processes, which are much faster than those accessible with a
conventional potentiostat, to be measured. It is able to inject
charge across the interface within a few nanoseconds, and also to
hold the potential generated across the cell following injection for
up to 1 s without appreciable (less than 1%) decay. In addition,
the circuit can still monitor the current flowing through the cell,
as in a conventional potentiostat. Preliminary test results with
both a dummy load and a custom two-electrode electrochemical
cell confirm the functionality of the proposed circuit.
