Adsorption and decomposition of CH 3NH 2 on Mo(100)-c(2 × 2)N

Abstract

The adsorption and decomposition of CH 3NH 3 on a Mo(100)-c(2 × 2)N surface has been studied using temperature-programmed desorption and Auger electron spectroscopy. The initial sticking coefficient for CH 3NH 2, at 210 K, is estimated to be ~ 10 −1, with the absolute value expected to be within a factor of three, and the maximum adsorption capacity is 0.28 ML. Temperature-programmed desorption studies show that adsorbed CH 3NH 2 undergoes desorption and concurrent decomposition. The major decomposition products are H 2, NH 3, C s, and N s. In addition, C 2H 4 is a minor decomposition product. D 2/CH 3NH 2 coadsorption studies suggest that the decomposition of adsorbed CH 3NH 2 is initiated by intramolecular hydrogen transfer to form adsorbed CH 2 and NH 3. Most of the CH 2 species undergo dehydrogenation to form C and H 2. Some of the adsorbed NH 3 decomposes to form N and H 2, but most of the NH 3 desorbs into the gas phase.