Electrocatalytic activity, of metals

Studies on the electrocatalytic activity of metal porphyrins are limited in comparison with those on other classes of macrocyclic metal complex. Among the few porphyrin complexes tested, cobalt porphyrins have been demonstrated to be efficient electrocatalysts for the reduction of C02 to CO... 

The search for correlations has even produced simply statistical approaches based on a combination of several properties of metals [68, 69]. It has been ascertained that the electrocatalytic activity of metals is a periodic function of the position of the metal in the Mendeleev Table [38, 70—72]. A strict correspondence is observed between two different periods (Fig. 3) indicating that metals in the same group occupy the same relative position in the various periods [60], Since all properties of metals... 

On examination of the electrocatalytic activity of metal nanoparticles in dark electrode processes, of significant interest is the appearance of the limiting current on the i,V curve for the Cu-modified Ti02 electrode, especially taking into account that it does not depend on the stirring of electrolyte and cannot be considered as a consequence of any diffusion limitation caused by the electrolyte solution. At the same time, this limiting current is very sensitive to the heating of the electrolyte as well as to the IR illumination of the electrode. 

To understand the above peculiarities of the electrocatalytic activity of metal nanophase in dark oxidation processes on the Ti02 electrodes, one should take into account the differences in the inherent electrocatalytic properties of deposited metals, on the one hand, and the data on the electronic states formed by the nanoparticles of these metals in a band gap of Ti02 electrode, on the other hand. A peculiar shape of i,V-curves obtained for... 

When one tries to correlate the electrocatalytic activity of metals with some fundamental property of the system, the result is often a "volcano- type" plot, as shown in Fig. 7F. 

A truly satisfactory explanation of these observations, which can be confirmed by independent experiments, has yet to be proposed. Tentatively it is argued that strongly adsorbed intermediates are formed during the oxidation of organic molecules. These intermediates block the surface and decrease its catalytic activity. Formation of a partial layer of lead atoms hinders the adsorption of such intermediates and thus allows the oxidation reaction to occur more readily on the remaining free platinum surface (or perhaps on parts of the surface covered by a monolayer of lead, which may retain much of the catalytic properties of the platinum substrate). This interpretation is attractive in that it is consistent with our general understanding of the electrocatalytic activity of metals (cf. Fig. 7F) but will have to be confirmed by other experiments before it can be accepted. 

The electrocatal5dic hydrogenation of cyclohexanone to cyclohexanol was carried out using various supported catalysts [4]. The hydrogen generation takes place on the metallic sites, whereas the organic substrate is adsorbed on alumina or activated carbon acting as support. The electrocatalytic activity of metals dispersed on alumina particles decreased in the order... 

Zagal JH, Paez M, Tanaka A, dos Santos Jr JR, Linkous CA (1992) Electrocatalytic activity of metal phthalocyanines for oxygen reduction. J Electroanal Chem 339(1-2) 13-30... 

Energy EDX Electrocatalytic activity of metal-porous Si EDX confirms the presence and the uniformity distribution of Pt Miu et al. (2010), Bilyalov et al. (2000), Zhan... 

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