Temperature-programmed reaction/desorption and reflection-absorption infrared spectroscopy have been employed to investigate the adsorption and decomposition of HOCH 2CH 2NH 2 on Cu(100). HOCH 2CH 2NH 2 molecules desorb from the multilayer and monolayer with a maximum rate at 203 and 255 K, respectively. The desorption state at 255 K corresponds to an adsorption energy of 66.0 kJ . mol -1 calculated for a firstorder kinetics with a preexponential factor of 10 13 s -1. RAIRS suggests that the multilayer and monolayer may be composed of different HOCH 2CH 2NH 2 rotational isomers. HOCH 2CH 2NH 2 can also decompose on Cu(100), approximately at the same temperature range of monolayer desorption, mainly to evolve H 2 and H 2O at ̃400 K. An Ar +-sputtered Cu(100) surface is found to promote the dissociation of HOCH 2CH 2NH 2. Temperature-dependent RAIRS, with the assistance of theoretical calculations based on density-functional theory, strongly suggests that HOCH 2CH 2NH 2 on Cu(100) dissociates first by losing a hydrogen atom to form -OCH 2CH 2NH 2, followed by transformation into HOCH 2CH 2N=. Decomposition of the latter species is responsible for the desorption of H 2 and H 2O.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films