The electrochem. properties of IrO2 nanoparticles deposited on a synthetic boron-doped diamond surface (BDD/IrO2) were investigated. After a description of the prepn. procedure by thermal decompn. technique, the morphol. characterization of the samples by SEM and TEM was discussed. The electrochem. behavior of the redox system 1,4-benzoquinone/hydroquinone (Q/H2Q) was studied on BDD electrodes with a different IrO2 loading. The kinetics parameters such the transfer coeffs. a and b and the reaction rate const. k0 were calcd. Oxygen evolution and oxidn. of org. compds. were investigated on both BDD and BDD/IrO2 electrodes by voltammetric measurements and preparative electrolysis. A phenomenol. model is proposed to explain the behavior of electrodes. [on SciFinder (R)]