Controllable synthesis of a 3D flower-like CeTiO_x composite oxide exposing CeO₂100 plane and it supported Au catalyst for CO oxidation

In this work, a flower-like CeTiO_x composite oxide, predominantly exposing CeO₂100 plane, was synthesized by a simple hydrothermal method. The SEM and XRD results revealed the growth mechanism of CeTiO_x composite oxide can be divided into two stages, including the rapid growth of amorphous and the following crystallization. The ratio of Ce/Ti, KOH concentration, crystallization time and calcination temperature are the key factors for the synthesis of the flower-like CeTiO_x composite oxide. Au catalyst supported on this composite oxide exhibited superior activity for CO oxidation at room temperature. The TEM and H₂-TPR results suggested that the exposed CeO₂100 plane and the strong interaction between Au and CeTiO_x composite oxide are responsible for the high activity.