Metal sintering in Rh/Al2O3 catalysts followed by HREM, 1 H NMR, and H2 chemisorption. Force, C., Ruiz Paniego, A., Guil, J., Gatica, J., López-Cartes, C., Bernal, S., & Sanz, J. Langmuir, 17(9):2720–2726, Instituto de Ciencia de Materiales de Madrid, CSIC, Campus Universitario de Cantoblanco, 28049 Madrid, Spain, 2001.
Metal sintering in Rh/Al2O3 catalysts followed by HREM, 1 H NMR, and H2 chemisorption [link]Paper  abstract   bibtex   
Hydrogen adsorption on Rh/Al2O3 catalysts sintered at increasing temperatures has been analyzed with high-resolution electron microscopy (HREM), proton nuclear magnetic resonance (1H NMR), and microcalorimetric techniques. The 1H NMR technique has been used to differentiate hydrogen adsorption on metal particles from that produced on the support. Metal dispersions estimated by HREM are intermediate between those deduced from volumetry and NMR techniques. Metal particle sizes deduced from HREM histograms, once weighted for surface effects, agree well with those determined by NMR but differ appreciably from those calculated from volumetric data. Observed differences have been ascribed to hydrogen retained on Al2O3 near Rh particles, that increases the NMR line located at the resonance frequency. The dependence of the NMR shift associated with hydrogen adsorbed on the rhodium is discussed in terms of metal particle size. In samples with low metal loadings, a partial coverage of metal particles with Al2O3 moieties, deposited during catalyst preparation, has been detected that reduces observed 1H NMR shifts.
@article{Force2001,
abstract = {Hydrogen adsorption on Rh/Al2O3 catalysts sintered at increasing temperatures has been analyzed with high-resolution electron microscopy (HREM), proton nuclear magnetic resonance (1H NMR), and microcalorimetric techniques. The 1H NMR technique has been used to differentiate hydrogen adsorption on metal particles from that produced on the support. Metal dispersions estimated by HREM are intermediate between those deduced from volumetry and NMR techniques. Metal particle sizes deduced from HREM histograms, once weighted for surface effects, agree well with those determined by NMR but differ appreciably from those calculated from volumetric data. Observed differences have been ascribed to hydrogen retained on Al2O3 near Rh particles, that increases the NMR line located at the resonance frequency. The dependence of the NMR shift associated with hydrogen adsorbed on the rhodium is discussed in terms of metal particle size. In samples with low metal loadings, a partial coverage of metal particles with Al2O3 moieties, deposited during catalyst preparation, has been detected that reduces observed 1H NMR shifts.},
address = {Instituto de Ciencia de Materiales de Madrid, CSIC, Campus Universitario de Cantoblanco, 28049 Madrid, Spain},
annote = {From Duplicate 1 ( Metal sintering in Rh/Al2O3 catalysts followed by HREM, 1 H NMR, and H2 chemisorption - Force, C; Ruiz Paniego, A; Guil, J M; Gatica, J M; L\'{o}pez-Cartes, C; Bernal, S; Sanz, J )

Cited By (since 1996): 9
        
Export Date: 22 January 2013
        
Source: Scopus
        
CODEN: LANGD
        
Language of Original Document: English
        
Correspondence Address: Force, C.; Inst. de Ciencia de Mat. de Madrid, CSIC, Campus Universitario de Cantoblanco, 28049 Madrid, Spain; email: Cforce@icmm.csic.es
        
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From Duplicate 2 ( Metal sintering in Rh/Al2O3 catalysts followed by HREM, 1 H NMR, and H2 chemisorption - Force C.a Ruiz Paniego, A.b Guil J.M.b Gatica J.M.c L\'{o}pez-Cartes C.c Bernal S.c Sanz J.a )

cited By (since 1996)10

},
author = {Force, C. and {Ruiz Paniego}, A. and Guil, JM. and Gatica, JM. and L\'{o}pez-Cartes, C. and Bernal, S. and Sanz, J.},
issn = {07437463},
journal = {Langmuir},
keywords = {Alumina,Catalysts,Chemisorption,Gas adsorption,High resolution electron microscopy,Hydrogen,Metal dispersions,Nuclear magnetic resonance,Particle size analysis,Rhodium compounds,Sintering,Surface phenomena,Thermal effects,Volumetric analysis},
number = {9},
pages = {2720--2726},
title = {{Metal sintering in Rh/Al2O3 catalysts followed by HREM, 1 H NMR, and H2 chemisorption}},
url = {https://www.scopus.com/inward/record.url?eid=2-s2.0-0035353329&partnerID=40&md5=3c17326739185d25bac3093bf576df6c http://www.scopus.com/inward/record.url?eid=2-s2.0-0035353329&partnerID=40&md5=e9c739cd54a46734209806bc4b1575b4},
volume = {17},
year = {2001}
}

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