HYDROGEN ADSORPTION ON RHODIUM PARTICLES SUPPORTED ON STRONTIUM-TITANATE AS FOLLOWED BY H-1-NMR AND MICROCALORIMETRY

Citation
Jm. Rojo et al., HYDROGEN ADSORPTION ON RHODIUM PARTICLES SUPPORTED ON STRONTIUM-TITANATE AS FOLLOWED BY H-1-NMR AND MICROCALORIMETRY, Journal of physical chemistry, 98(51), 1994, pp. 13631-13635
Citations number
35
Categorie Soggetti
Chemistry Physical
ISSN journal
00223654
Volume
98
Issue
51
Year of publication
1994
Pages
13631 - 13635
Database
ISI
SICI code
0022-3654(1994)98:51<13631:HAORPS>2.0.ZU;2-A
Abstract
Hydrogen adsorption on supported rhodium particles has been studied by H-1 NMR, volumetry, and microcalorimetry techniques, The amounts of h ydrogen adsorbed on the metal and support have been evaluated. There i s a good correlation between the shift of the NMR Line assigned to hyd rogen adsorbed on the metal and the mean integral heat involved in thi s adsorption. This permits an estimation of differential shifts corres ponding to each dose. From analysis of differential NMR shift and diff erential adsorption heat, it is deduced that the hydrogen-metal intera ction becomes weaker and less energetic with adsorption. This effect i s discussed on the basis of the heterogeneity of the adsorption sites and a modification of the electronic properties at the metal surface.