An XPS Study of the Interaction of NO2 with Sibunit in the Presence of Supported Palladium Particles
M. Yu. Smirnov, А. В. Калинкин, Alexandr N. Simonov, V. I. Bukhtiyarov
Abstract
The interaction of NO2 with a carbon material from the Sibunit family with palladium metal particles supported on its surface was studied by X-ray photoelectron spectroscopy (XPS) at a pressure of 10–6 mbar in a temperature range from room temperature to 300°C. Two Pd/Sibunit samples, one of which was prepared by chemical deposition of palladium (Pd/C-HC sample) and the other, by vacuum evaporation of the metal onto the support (Pd/C-VE sample), were studied. Both of the samples showed similar behaviors in the interaction with NO2. Over the entire temperature range, the C1s spectrum of the samples contained a single peak with a binding energy of 284.4 eV from carbon atoms in the sp2-hybrid state, which indicated a weak effect of NO2 on Sibunit. At temperatures from room temperature to 150°C, the state of palladium supported onto the surface of Sibunit also did not change, but palladium was partially oxidized with the formation of PdO in a range from 200 to 300°C.