Monday, 30 May 2022: 10:50
West Meeting Room 114 (Vancouver Convention Center)
Overpotential, defined by IUPAC as the 'deviation of the potential of an electrode from its equilibrium value' is a key parameter in electrodeposition, as it is in other areas of electrochemistry. However, care is required when dividing the overpotential into contributions such as transport overpotential, activation overpotential etc. The concept of 'nucleation overpotential' is especially open to abuse, as I shall demonstrate with the help of examples from the literature. To avoid misunderstanding, it is necessary to recognize that when deposition takes place via the formation of reduced mobile adatoms, the key quantity for both nucleation and growth is the difference between the adatom chemical potential and the chemical potential of metal atoms at the so-called half-crystal position.