Electron optical characterization of a supported rhodium catalyst

Abstract Both fresh and reduced V 2 O 5 -supported rhodium catalyst prepared by wet impregnation were characterized by temperature-programmed reduction, CO gas chemisorption (CO-GC), X-ray diffraction and IR spectroscopy. Complementary structural and morphological investigations were carried out using scanning (SEM) and transmission electron microscopics (TEM). Reduction of the catalyst at 250°C in hydrogen led to a predominant support reduction to V 4 O 9 . Rhodium particles with different shapes and sizes were observed on the surface of this support. The distribution of particle sizes determined from TEM images is compared with that obtained from CO-GC.