Low-temperature, high external magnetic field Mössbauer spectroscopy and ferromagnetic resnance were used to characterize iron and iron-ruthenium bimetallic catalysts derived from molecular clusters and supported on Cab-O-Sil. The Ru Fe ratio varied between 1.6 and 6.0. These two methods enabled it to be unambiguously established that paramagnetic iron-ruthenium bimetallic particles of high dispersion are always present along with iron oxide after reduction at high temperature and in the CO + H2 reaction. Thus, for the catalysts investigated earlier (see J. Catal. 87, 179, 1984) the catalytic behavior is attributable to iron-ruthenium bimetallic particles. A value of 3 nm has been estimated for the diameter of ferromagnetic metallic particles.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry