Investigation of behaviour of Rh deposited onto polycrystalline SnO2 by means of TPD, AES and EELS

Rh films deposited onto a SnO2 polycrystalline substrate were used to study CO adsorption in dependence on the amount of deposited rhodium. The sample purity and composition were investigated by means of Auger electron spectroscopy, the development of a surface electronic structure by electron energy loss spectroscopy. Temperature programmed desorption (TPD) was used to follow the adsorption of CO. The behaviour of Rh deposit stimulated by the annealing and CO adsorption was monitored by a variation of CO desorption energy and an area of the TPD peak. The CO adsorption capacity of sample and stimulation energy of CO desorption decrease if the TPD experiments are repeated. During these experiments the Auger spectra exhibited the presence of a metallic Sn on the surface.