Preparation of Rh/CeO2 using supercritical CO2 and its catalytic application for automotive exhaust

Abstract

Rh/CeO2 catalysts were investigated for automotive catalysts prepared by a supercritical CO2 impregnation technique. Energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used for the analysis of the Rh loading, Rh structure, and the morphology of the particles, respectively. Results of TEM and XRD showed Rh particles are highly dispersed on CeO 2 surface, and Rh/CeO2 after calcination were prevented aggregation of CeO2. OSC of Rh/CeO2 prepared by supercritical impregnation method was higher than those of conventional catalysts. The catalytic tests for three way catalysts (TWC) showed high CO oxidation activity obtained using Rh/CeO2 prepared by supercritical impregnation. Thus, it was concluded that supercritical CO2 impregnation technique can improve OSC and TWC activity.