Binary rare-earth ceria-ytterbia and ceria-dysprosia and pure CeO2 have been subjected to CO2-laser irradiation. All the samples have been prepared by precipitation and controlled drying. Irradiated samples as well as the samples calcinated at 1273 K have been studied using TG-DTA, TEM and SAED, WAXS and FT-IR. Introduction of a second rare-earth oxide, like ytterbia or dysprosia led to an important increase of 'stability' towards the CO2-laser irradiation. Thermal investigation of these samples revealed in fact a 'metastability' because, for the temperatures of about 500 K, a release of oxygen has been observed. This behaviour could recommend CO2-laser irradiation as a possible alternative for activation of the oxidation catalysts.