ADSORPTION AND PARTIAL CHARGE-TRANSFER AT DIAMOND ELECTRODES .1. PHENOMENOLOGY - AN IMPEDANCE STUDY

Impedance spectra of semiconducting polycrystalline and single crystal diamond specimens were studied in aqueous electrolytes under ideally polarizable (blocking) and non-polarizable conditions. The dispersive impedance of the samples in the blocking case is probably unrelated to the roughness of the polycrystalline films and appears as an inherent property of the interface. Different samples are seen to have differe nt electrocatalytic activity. Diffusion-controlled partial charge tran sfer was proven to take place on the most active specimens which are p romising candidates for non-corrosive, dimensionally stable photoelect rodes.