XPS AND IN-SITU IR INVESTIGATION OF RU SIO2 CATALYST/

Ru(NO)(NO3)(3)/SiO2 catalyst precursors were characterized via XPS and in-situ reflectance IR spectroscopy before, during and after reductio n by hydrogen over the temperature range 300-800 K. IR results indicat ed that the catalyst precursor lost NO3 groups first, with subsequent loss of NO both in a reducing atmosphere and during thermal annealing. XPS was used to derive information on the oxidation state of Ru in th e various steps of the annealing and/or reduction processes. (C) 1997 Elsevier Science B.V.