H2 Adsorption in Rhodium metal catalysts supported in oxides with different reducibility

Nuclear Magnetic Resonance has been used to monitor hydrogen spill-over in different rhodium metal supported catalysts. The detection of two lines in the NMR spectra allowed the differentiation of hydrogen adsorbed on Rh particles and on oxides used as supports. The study of intensities of these lines vs . pH 2 showed that hydrogen transferred to the support is favoured in metal catalysts supported on high hydroxylated reducible oxides. Spill-over depends on the area and nature of metal support interfaces, detecting some differences with the precursor metal salt used in catalyst preparation.