(1. 湖南科技大学 化学化工学院，湘潭 411201；
2. 中南大学 粉末冶金研究院，长沙 410083)
摘 要: 分别以柠檬酸(CA)、聚乙二醇(PEG)和淀粉(ST)为添加剂，采用共沉淀法制备CeO2-ZrO2-Al2O3(CZA)复合氧化物储氧材料，利用XRD、TG/DSC、SEM、N2吸附-脱附、氧脉冲吸附和程序升温还原等检测方法对材料性能进行表征。XRD结果表明:ST添加剂的样品经1000 ℃煅烧后产物主要为CeO2和γ-Al2O3，添加CA与PEG的样品为CeO2-ZrO2相，并夹带少量γ-Al2O3相；经1100 ℃煅烧后，3种添加剂样品都主要为CeO2-ZrO2晶相。SEM结果表明:CA、ST和PEG添加剂样品经1000 ℃高温处理后，分别为颗粒状、蜂窝状和多孔网状结构。N2吸附-脱附结果表明:经600 ℃热处理后，ST添加剂样品具有最大的比表面积234.95 m2/g和孔容1.589 cm3/g；经1000 ℃热处理后，添加PEG样品获得最大的比表面积、孔容和孔径，其值分别为92.50 m2/g、0.702 cm3/g和29.84 nm，且有最佳的孔分布和吸附-脱附能力。储氧性能OSC和H2-TPR结果表明:PEG添加剂制备的材料具有最好的储氧能力(OSC)和还原性能；1100 ℃高温下，ST添加剂样品的结构特性与PEG的接近；而CA添加剂样品的吸附能力、储氧性能都相对较低。
关键字: CeO2-ZrO2-Al2O3；储氧材料；添加剂；结构；性能
（1. School of Chemistry and Chemical Engineering, Hunan University of Science and Technology,
Xiangtan 411201, China;
2. College of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:CeO2-ZrO2-Al2O3 oxygen storage materials were prepared by coprecipitation method using citric acid (CA), starch (ST) and polyethylene glycol (PEG) as organic additives. The material performances were characterized by X-ray diffraction (XRD), TG/DSC, SEM, N2 adsorption-desorption, oxygen pulse adsorption and H2 temperature -programmed reduction (H2-TPR). The XRD results show that the sample with starch-additive has CeO2 and γ-Al2O3 phases, while the samples with citric acid and polyethylene glycol additives mainly have CeO2-ZrO2 cubic fluorite and only a little γ-Al2O3 phases after sintered at 1000 ℃. The samples are major CeO2-ZrO2 solid solution crystal phase with three additives after sintered at 1100 ℃. The SEM results display that the products are particulate with citric acid additive, the products are honeycomb with starch additive, and the products are porous with polyethylene glycol additive. The N2 adsorption-desorption results demonstrate that the sample facilitated by starch additive has the largest specific surface area of 234.95 m2/g, highest pore volume of 1.589 cm3/g after sintered 600 ℃. When sintered at 1000 ℃, the sample by polyethylene glycol additives-modified method possesses the largest specific surface area (92.50 m2/g), pore volume (0.702 cm3/g) and pore diameter (29.84 nm), the best pore size distribution and adsorption-desorption capacity. The results of oxygen storage and H2-TPR indicate that the samples prepared with polyethylene glycol additives have the best oxygen storage performance (OSC) and reduction capacity. The structural characteristics of the samples calcined at 1100 ℃ with starch additive exhibit proximity to that of samples prepared with polyethylene glycol additives. The samples synthesized with citric acid additive show relatively lower adsorption and oxygen storage performance.
Key words: CeO2-ZrO2-Al2O3; oxygen storage material; additive; structure; performance
