Fabrication of a flower-like Pd/CeO2 material with improved three-way catalytic performance

Pd/CeO₂ catalysts with flower-like morphology were fabricated via an ultrasonic-assisted membrane reduction (UAMR) and hydrothermal methods. The catalysts were physically characterized and evaluated for three-way catalytic activities versus traditional Pd/CeO₂ catalysts. Flower-like Pd/CeO₂ catalysts exhibited a higher catalytic performance and better thermal stability than the Pd/CeO₂ prepared by conventional impregnation. The flower-like Pd/CeO₂ catalysts were constructed from 20–50 nm thick nanosheet petals. These petals were in turn constructed from 10 nm CeO₂ nanoparticles that self-assembled into the flower-like morphology resulting in abundant pores in all directions. The Pd nanoparticles were anchored and dispersed on both the interior and surface of the pores and had minimal sintering. When these catalysts were aged, the structure and morphology of the catalysts remained unchanged with important industrial implications for this new type of material including improved catalytic performance and high thermal stability. Regardless of the Pd loading, both the fresh and aged Pd/CeO₂ catalysts prepared by the UAMR-hydrothermal method exhibited better performance than the corresponding samples prepared by conventional impregnation means.