Designed synthesis of Zr-based ceria–zirconia–neodymia composite with high thermal stability and its enhanced catalytic performance for Rh-only three-way catalyst

Abstract

Developing advanced oxygen storage materials that deliver high thermal stability is crucial to meeting increasingly stringent environmental regulations for three-way catalysts (TWCs). The surfactant, trialkylamine (N235, N (C_nH_2n+1), n = 8–10), was used to prepare the zirconium (Zr)-based ceria–zirconia–neodymia composites with loose morphology for the first time, and the effect of N235 on the properties of the ceria–zirconia–neodymia solid solution composites was investigated systematically. After thermal treatment at 1000 °C for 5 h in air, the obtained material (CZ/N235-1000) presented a high surface area of 31 m² g⁻¹ and had superior redox properties. As a support material in rhodium (Rh)-only TWCs, the prepared Rh/CZ/N235-f and Rh/CZ/N235-a demonstrated excellent catalytic performances. Particularly, after aging at 1000 °C for 5 h in air, the light off temperature (T_50%) of nitrogen oxide and carbon monoxide for Rh/CZ/N235-a were 229 °C and 235 °C, respectively, and were much lower than those (278 °C and 280 °C) of Rh/CZ-a in which the support material was synthesized without N235. Therefore, this work provides a simple and scalable synthesis route for advanced oxygen storage materials.