Potential intermediate in CH4-assisted reduction of nitric oxide: the reactions of methyl nitrite on oxidized Mo(1 1 0)

Abstract The reactions of methyl nitrite (CH 3 ONO) on O-covered Mo(1 1 0) were studied in order to determine whether methyl nitrite is a possible intermediate in CH 4 -assisted reduction of NO. Methyl nitrite decomposes to NO and methoxy (CH 3 O ads ) upon adsorption at low temperature. Most NO is evolved directly into the gas phase at 110 K, although a small fraction is trapped on the surface and is identified using infrared spectroscopy. Methoxy remains on the surface until ∼600 K, at which point it decomposes to gas phase • CH 3 and adsorbed oxygen. Hence, the overall reaction is the reverse of the • CH 3 + NO reaction. However, no reduction products (N 2 or N 2 O) are evolved. The absence of reduction may be due to the fact that all high coordination sites are occupied on the O-covered surface or to the low coverage of NO. These results are discussed in the context of • CH 3 -assisted NO reduction.