Adsorption and Decomposition of Methanol on NiAl(110)

Article abstract of DOI:10.1021/j100091a048

Methanol adsorption and reaction on NiAl(110) have been investigated with temperature-programmed desorption, X-ray and ultraviolet photoelectron spectroscopy, and high-resolution electron energy loss spectroscopy.Methanol chemisorbs associatively (at least relatively high coverage) on NiAl(110) at 120 K and transforms into surface methoxy by 200 K.Decomposition of the methoxy overlayer leads to the evolution of gaseous H2, CO, CH4, and CH3 radicals, in addition to the deposition of surface oxygen and carbonaceous species.The formation of C2H4 is also observed after a high coverage of methoxy decomposes on NiAl(119).Methyl radical desorption occurs near 570 K and CH4 desorbs near 350 K from NiAl(110).The low-temperature CH4 desorption peak indicates that the C-O bond of a fraction of surface methoxy is cleaved below 350 K on NiAl(110), in contrast to monometallic Al and Ni, emphasizing the unique reactivity of this alloy surface.