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The kinetics of CO oxidation on heterophase surfaces composed of two different types of patches M1 and M2 is analyzed. The kinetic conjugation of the patches caused by COads spillover leads to the substantial change in reaction rate temperature dependences, as well as to the appearance of a low-temperature, superadditive activity.

The homotopic method has been used to analyze the kinetic models of CO oxidation on two surface patches conjugated by COads spillover. On each patch reaction proceeds via a three-stage mechanism but with different constants. The stability of steady-states solution has been studied. COads spillover from one patch to another changes substantially the bifurcation picture of steady states and produces islands.

The interaction of CO and O2 on the oxidized surface of polycrystalline palladium under steady state reaction conditions has been studied. The adsorption of carbon monoxide leads to the appearance of its α and β states. The β state on the surface shifts the temperature dependence of the CO oxidation rate under s.s. conditions by about 200 K.

Homotopic method has been used to analyze the kinetic model of three-stageCO oxidation on two nonuniform surface patches conjugated byCOads spillover. The diagrams of steady states depending onP(CO) at various temperatures have been built.COads spillover from one patch to another changes substantially the bifurcation picture of the steady states.

The homotopic method has been used to analyze the kinetic model of three-stageCO oxidation on two nonuniform surface patches conjugated byCO2 spillover. Diagrams of steady states depending on the portion of surface patchm1 at various temperatures and pressure ratiosP(O2)/P(CO) have been constructed. The ratios of different type patches corresponding to the maximum overall reaction rate have been found.

O2 and CO adsorption on Ru(001) plane has been studied by Auger electron spectroscopic and thermal desorption techniques. It is shown that the oxygen nonreconstructively adsorbed at 300 K, transforms upon heating to the state of sub-surface oxide. Bond energy and ΘCO of carbon monoxide depends on the ΘO and the state of prechemisorbed oxygen.

LEED, AES and TPD studies of CO adsorption at 170 K on the oxygen-covered surface of Ni(100) have revealed its great amount throughout the range of oxygen coverage. With thermal desorption from a mixed layer the appearance of CO2 due to the reaction COads+Oads, indicates that a part of oxygen adsorbed on Ni(100) at T=170 K is reactive.