Coverage dependence of the kinetics of H sub 2 desorption from Rh(111)

• Published in: Surface science Vol. 366; no. 1; pp. 19 - 28
• Main Authors: Sibener, S J, Colonell, J I, Curtiss, T J
• Format: Journal Article
• Language: English
• Published: 10-10-1996
• ISSN: 0039-6028

Coverage dependent sticking probabilities and second order rate constants for recombinative desorption of hydrogen from Rh(111) were measured using molecular beam relaxation spectroscopy (MBRS) and time resolved specular helium scattering. The sticking probability follows second order Langmuir coverage dependence, with s sub 0 equal to 0.01plus/minus0.005. Under isothermal and nearly isosteric conditions over the coverage range 0.2-0.7 ML, the second order rate constant for desorption was essentially independent of hydrogen coverage, in contrast to kinetic parameters determined from thermal desorption spectra.