Effects of co-precipitation temperature on structure and properties of La and Y doped cerium zirconium mixed oxides

Abstract

Due to the oxygen storage and release properties, cerium zirconium mixed oxides are recognized as the key material in automotive three-way catalysts. To reveal the effects of co-precipitation temperature on structure, physical and chemical properties of multi-doped cerium zirconium mixed oxides, a series of La and Y doped cerium zirconium mixed oxides (CZLYs) were synthesized via a co-precipitation method, and the physical and chemical properties of CZLYs were systemically characterized by XRD, N2 adsorption–desorption, TEM, XPS, oxygen storage capacity (OSC) and hydrogen temperature programmed reduction (H2-TPR). The results show that co-precipitation temperature is an important parameter to influence the crystal size, oxygen storage capacity and thermal stability of CZLYs. When the co-precipitation temperature was 60 °C, the best redox properties and thermal stability of CZLYs were obtained. After thermal treatment at 1100 °C for 10 h, the specific surface area and oxygen storage capacity of the corresponding aged sample were 15.42 m2/g and 497.7 μmol/g, respectively. In addition, a mechanism was proposed to reveal the effects of co-precipitation temperature on the structure and properties of CZLYs.