Detection principle for a chemically modified electrode (CME) in which a charge transfer reaction between a CME and analyte proceeds at a lower overpotential than at the bare electrode. Usually, the effect of electrocatalysis is also an increase of faradaic current.

Note: Electrocatalysis at a CME must be distinguished from redox mediation.

Examples: Hydrogen evolution at HMDE catalyzed by adsorbed organic bases, oxygen reduction, water oxidation, hydroxylamine oxidation at CME with metal complex compounds as the electrocatalyst.