Abstract Cerium zirconium solid solution is a key washcoat material for automotive three-way catalysts (TWCs). However, improving the redox ability and high temperature thermal stability of cerium zirconium solid solution is still a challenge. In this paper, the cerium zirconium solid solution was prepared by a coprecipitation-hydrothermal method, and the effects of the ammonia concentration on their structures and redox properties were investigated. The results show that when the ammonia concentration is 0.8 mol/L, the aged sample (1100 °C/10 h) of cerium zirconium solid solution has the highest specific surface area of 23.01 m2/g. Additionally, the increase of ammonia concentration improves the uniformity of phase compositions and increases the oxygen vacancies. When the ammonia concentration reaches at 0.4 mol/L, the cerium zirconium solid solution exhibits the best redox activity, with the lowest reduction temperature of 565 °C. Therefore, increasing ammonia concentration in the hydrothermal treatment is beneficial to the thermal stability and redox performance of cerium zirconium solid solution.

中文翻译：

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水热处理氨浓度对铈锆固溶体结构和氧化还原性能的影响

摘要 铈锆固溶体是汽车三元催化剂（TWCs）的关键涂层材料。然而，提高铈锆固溶体的氧化还原能力和高温热稳定性仍然是一个挑战。本文采用共沉淀-水热法制备了铈锆固溶体，研究了氨浓度对其结构和氧化还原性能的影响。结果表明，当氨气浓度为0.8 mol/L时，铈锆固溶体老化样品（1100℃/10 h）的比表面积最高，为23.01 m2/g。此外，氨浓度的增加改善了相组成的均匀性并增加了氧空位。当氨浓度达到 0.4 mol/L 时，铈锆固溶体表现出最好的氧化还原活性，最低还原温度为565℃。因此，在水热处理中增加氨浓度有利于铈锆固溶体的热稳定性和氧化还原性能。