The cyclic voltammetry response of partially blocked electrodes is modeled using finite difference simulations and a method presented for determining currents at electrode surfaces which have a well-defined geometric blocking pattern. Peak current and peak separation data are presented for six decades of scan rates, blocking coverage values between 0.1 and 0.9 and between the limits of reversible and irreversible electrochemistry. The validity of the simulation approach employed is verified by data obtained experimentally from purpose-built partially blocked gold film electrodes, with either a cubic or hexagonal geometric array of electroinactive disks uniformly distributed on the electrode surface. Comparison of theory with experiment suggests that the modeling of hexagonally distributed blocking systems is superior to that of the cubically arranged ones.

The cyclic voltammetric response of partially blocked electrodes is modeled using finite difference simulations, and a method is presented for the determination of currents at electrode surfaces that have an unstructured blocking pattern. The method is first applied to predict the current at purposely fabricated gold film electrodes in which monodispersed blocking disks are randomly sprinkled over the gold surface. The theoretical models are subsequently applied to the case of a basal plane pyrolytic graphite electrode modified with microdroplets of an electrochemically inactive oil. The theoretically predicted results are in good agreement with those observed experimentally.

The electro-reduction of carbon dioxide is studied by linear sweep and cyclic voltammetry in DMSO electrolyte solutions and at polycrystalline gold microdisk electrodes. An electrode reaction pathway is suggested. Numerical simulation of the reaction mechanism gives current | potential waveshapes in excellent agreement with those observed experimentally. Kinetic parameters for the reduction process are deduced from this waveshape approach, and the charge-transfer coefficient is found to be approximately 0.43 ( 0.05.