TEMPERATURE HYSTERESIS IN OXIDATION OF CO ON COMPLEX OXIDE CATALYSTS

We have used thermal desorption (TD) with mass spectrometric detection of the desorbed species to study the state of the surface of oxide catalysts for oxidation of CO. Detection of weakly bound forms of water and the species H3O+ and HO2 in the thermal desorption spectra correlates with the existence of temperature hysteresis in these samples. The data obtained are explained by the reaction occurring in a highly active state via a heterogeneous–homogeneous mechanism, and also by the effect of local superheating.