Temperature dependent reaction of propene on Ni(100) single crystal surfaces

Abstract The reaction behaviour of propene on Ni(100) single crystals was studied by photoelectron spectroscopy (XPS), thermal desorption spectroscopy (TDS) and low energy electron diffraction (LEED). Propene is molecularly adsorbed at temperatures below 150 K. For the saturated layer, 80% of the adsorbed propene decomposes upon heating, as indicated by hydrogen desorption; only 20% desorbs molecularly with desorption peaks at 160 and 225 K. No other desorbing species can be observed. After complete dehydrogenation of propene at 500 K the remaining carbon species form a p4g-(2×2)C structure. The corresponding XP spectra show two distinct C1s peaks, probably due to carbon species located in different adsorption sites. Further increase of the temperature of the Ni(100) crystal to 610 K results in a small shift of the binding energies but without any changes in the LEED pattern.