Hydrothermal Synthesis of Rare-Earth Oxide Nanocatalysts for Automotive Exhaust Clean-Up

Abstract

Three rare-earth metal oxide nanopowders (CeO2, PrO2, and TbO2) were synthesized using a facile hydrothermal method in a Teflon-lined autoclave. The rare-earth metal oxide nanocrystals with variable morphology were prepared by controlling the synthesis conditions with temperatures in the range of 70−220 °C. X-ray diffraction (XRD), thermal gravimetric analysis (TGA), and temperature programmed reduction (TPR) were used to characterize the average structures and redox properties of these materials. Transmission electron microscopy (TEM) was used to investigate the morphology, particle size, and formation and growth mechanisms of the rare-earth metal oxide nanoparticles in solution-based environment.