FTIR studies of CO adsorption on Rh-Ge/Al2O3 catalysts prepared by surface redox reactions.
A series of bimetallic Al2O3-supported Rh-Ge catalysts was prepared by surface redox reactions under controlled hydrogen atmosphere. The surface properties of these catalysts were probed via in-situ FTIR spectroscopic studies of adsorbed CO and were compared to those of monometallic Rh catalysts that had undergone similar treatments. The results indicate that Ge addition results in the formation and stabilization of smaller rhodium ensembles at the expense of larger Rh0 surfaces. A charge-transfer mechanism from Ge to Rh is also inferred by the IR results for the high Ge loading samples. Air exposure of the catalysts leads to an irreversible segregation of the two metals and formation of large Rh crystallites.
Lafaye
Gwendoline
G
Laboratoire de Catalyse en Chimie Organique, UMR CNRS 6503 Université de Poitiers, 40 Avenue du Recteur Pineau, F-86022 Poitiers Cedex, France.
Mihut
Corina
C
Especel
Catherine
C
Marécot
Patrice
P
Amiridis
Michael D
MD
D000327:Adsorption; D000537:Aluminum Oxide / Q000737:chemistry*; D002248:Carbon Monoxide / Q000737:chemistry*; D002384:Catalysis; D005857:Germanium / Q000737:chemistry*; D010084:Oxidation-Reduction; D012238:Rhodium / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D013499:Surface Properties
D005857:Germanium; D002248:Carbon Monoxide; D012238:Rhodium; D000537:Aluminum Oxide