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Electrocatalytic activity of common noble metal (platinum, bimetallic platinum-ruthenium and palladium) nanoparticles (both unsupported and supported on Vulcan carriers) toward electrooxidation of formic acid in acid medium (0.5 mol dm–3 H2SO4) can be significantly enhanced by dispersing them over thin film of zirconia (ZrO2). The enhancement effects concern increases of the electrocatalytic current densities (normalized against the mass of noble metal catalysts) recorded under both cyclic voltammetric and chronoamperometric conditions. The observations can be rationalized in terms of the ability of zirconia nanostructures to provide active hydroxyl groups capable of inducing the removal of the inhibiting COOH or CO type adsorbates from their surfaces. The role of Vulcan carriers is in improving electronic conductivity, in addition to facilitating distribution of catalytic metal sites at the electrocatalytic interface. Regarding dissimilar mechanisms for HCOOH oxidations at Pt, PtRu and Pd nanoparticles, the activating capabilities of zirconia differ depending on the potential applied thus reflecting distinct nature of electronic or chemical interactions. Specific interactions between the zirconia support and noble metal nanoparticles are also possible, particularly in the case of Pd-based catalysts where the enhancement effects are the most pronounced. Finally, it should be emphasized that, historically, representatives of Russian school of electrochemistry, including V.S. Bagotsky, were one of the first world-wide who investigated the formic acid oxidation and emphasized the importance of metal—support interactions during electrooxidation of small organic molecules at noble metal nanoparticles.

Carbon is nonmetal and lead is a typical metal, while silicon and germanium exhibit semiconducting properties. Compounds with hydrogen are stable and common for carbon, but the number of such compounds for silicon and germanium becomes limited, and for lead, only one unstable compound of that type is known. The chemistry of the divalent state is more important for heavier elements and the basicity of oxides increases from carbon to lead. Carbon forms a great number of compounds with different oxidation states. The characteristic feature of carbon is significant stability in both the +4 and -4 valence state compounds. Only the potentials of those compounds of carbon that are traditionally grouped with inorganic substances. The electrode reactions of silicon species are slow under normal conditions, which may follow from the fact that the bonds of silicon with other atoms are quite strong.

Research carried out in the Laboratory of Professor Wiktor Kemula and his coworkers at the University of Warsaw in time of a divided world is described briefly. The description starts from the early works of Professor at the University of Jan Kazimierz in Lvov and ends around 1990, when important political transformations occured in Europe. Difficulties in research work, resulting from a divided world, of this laboratory and other electrochemical laboratories in Poland are presented.