%0 Journal Article %1 Campbell1981a %A Campbell, C.T. %A Ertl, G. %A Kuipers, H. %A Segner, J. %D 1981 %J Surf. Sci. %K oxygen; platinum, science, surface %N 1 %P 220 - 236 %R DOI: 10.1016/0039-6028(81)90622-1 %T A molecular beam study of the adsorption and desorption of oxygen from a Pt(111) surface %U http://www.sciencedirect.com/science/article/B6TVX-46TYBPY-1B/2/c6dc481974893f7f971620bf2fc73d8e %V 107 %X The adsorption and desorption of O2 on a Pt(111) surface have been studied using molecular beam/surface scattering techniques, in combination with AES and LEED for surface characterization. Dissociative adsorption occurs with an initial sticking probability which decreases from 0.06 at 300 K to 0.025 at 600 K. These results indicate that adsorption occurs through a weakly-held state, which is also supported by a diffuse fraction seen in the angular distribution of scattered O2 flux. Predominately specular scattering, however, indicates that failure to stick is largely related to failure to accommodate in the molecular adsorption state. Thermal desorption results can be fit by a desorption rate constant with pre-exponential nud = 2.4 � 10-2 cm2 s-1 and activation energy ED which decreases from 51 to 42 kcal/mole-1 with increasing coverage. A forward peaking of the angular distribution of desorbing O2 flux suggests that part of the adsorbed oxygen atoms combine and are ejected from the surface without fully accomodating in the molecular adsorption state. A slight dependance of the dissociative sticking probability upon the angle of beam incidence further supports this contention.

@article{Campbell1981a, abstract = {The adsorption and desorption of O2 on a Pt(111) surface have been studied using molecular beam/surface scattering techniques, in combination with AES and LEED for surface characterization. Dissociative adsorption occurs with an initial sticking probability which decreases from 0.06 at 300 K to 0.025 at 600 K. These results indicate that adsorption occurs through a weakly-held state, which is also supported by a diffuse fraction seen in the angular distribution of scattered O2 flux. Predominately specular scattering, however, indicates that failure to stick is largely related to failure to accommodate in the molecular adsorption state. Thermal desorption results can be fit by a desorption rate constant with pre-exponential [nu]d = 2.4 � 10-2 cm2 s-1 and activation energy ED which decreases from 51 to 42 kcal/mole-1 with increasing coverage. A forward peaking of the angular distribution of desorbing O2 flux suggests that part of the adsorbed oxygen atoms combine and are ejected from the surface without fully accomodating in the molecular adsorption state. A slight dependance of the dissociative sticking probability upon the angle of beam incidence further supports this contention.}, added-at = {2009-10-30T10:04:05.000+0100}, author = {Campbell, C.T. and Ertl, G. and Kuipers, H. and Segner, J.}, biburl = {https://www.bibsonomy.org/bibtex/22b208b976f4e110a882a89b0fcfdd736/jfischer}, doi = {DOI: 10.1016/0039-6028(81)90622-1}, interhash = {a1ab73decbee84c5e47b2d414b3db4ec}, intrahash = {2b208b976f4e110a882a89b0fcfdd736}, issn = {0039-6028}, journal = {Surf. Sci.}, keywords = {oxygen; platinum, science, surface}, number = 1, pages = {220 - 236}, timestamp = {2009-10-30T10:04:10.000+0100}, title = {A molecular beam study of the adsorption and desorption of oxygen from a Pt(111) surface}, url = {http://www.sciencedirect.com/science/article/B6TVX-46TYBPY-1B/2/c6dc481974893f7f971620bf2fc73d8e}, volume = 107, year = 1981 }