铈锆比对低贵金属Pt+Rh/Ce_(0.3+x)Zr_(0．6-x)Y_(0．1)O_(1．95)+Al_2O_3三效催化剂性能的影响  

Effects of Cerium/Zirconium Ratio on the Property of Low Noble Metal Pt+Rh/Ce_(0.3+x)Zr_(0.6-x)Y_(0.1)O_(1.95)+Al_2O_3 Three Way Catalysts

作　　者：毛小波[1] 陈耀强[1] 赵明[1] 袁书华[1] 李俊强[1] 龚茂初[1] 

机构地区：[1]四川大学化学学院

出　　处：《化学学报》2007年第4期300-304,共5页Acta Chimica Sinica

基　　金：国家自然科学基金(No.20273043);国家重点基金(No.20333030)资助项目.

摘　　要：用共沉淀法制得一系列铈锆比不同的Ce_(0．3+x)Zr_(0．6-x)Y_(0．1)O_(1．95)储氧材料,并用于制备了一系列低贵金属Pt+ Rh/Ce_(0．3+x)Zr_(0．6-x)Y_(0．1)O_(1．95)+Al_2O_3三效催化剂．用比表面、程序升温还原以及X射线衍射对该系列催化剂进行表征,结果发现,催化剂的活性与催化剂中贵金属的还原性能密切相关,低铈储氧材料比高铈储氧材料更有利于促进贵金属还原,因而含低铈储氧材料催化剂的活性明显优于含高铈储氧材料催化剂的活性,Pt+Rh/Ce_(0．35)Zr_(0．55)Y_(0．1)O_(1．95)+Al_2O_3的活性最佳,对HC,CO和NO的起燃温度最低分别为:235,175,200℃．样品经1000℃水热老化之后,贵金属Pt被烧结而发生迁移,使得催化剂的活性及还原性能变差,含低铈材料的催化剂的抗老化性能优于含高铈材料的催化剂,其中Pt+ Rh/Ce_(0．35)Zr_(0．55)Y_(0．1)O_(1．95)+Al_2O_3的抗老化性能最好．A series of materials Ce0.3＋xZr0.6-xY0.1O1.95 were prepared by co-precipitation route, and these materials were used to prepare low noble metal Pt＋Rh/Ce0.3＋xZr0.6-xY0.1O1.95＋Al2O3 three way catalysts. The properties of the series of catalysts were studied by SBET, temperature programmed reduction and X-ray diffraction. It was found that the reducibility was closely related to the catalytic performance, and the reducibility of the catalysts containing low cerium content oxygen storage material was better than that of the catalysts containing high cerium content oxygen storage material. The catalytic performance of the catalysts containing low cerium content oxygen storage material was better than that of the catalysts containing high cerium content oxygen storage material. The catalyst Pt＋Rh/Ce0.35Zr0.55Y0.1O1.95＋Al2O3 possessed the best catalytic performance （the light-off temperature for HC, CO and NO conversion was 235, 175 and 200 ℃, respectively）. After 1000 ℃ hydrothermal aging, the reducibility and catalytic performance were dropped, the thermal stability of the catalysts containing low cerium content oxygen storage material was better than that of the catalysts containing high cerium content oxygen storage material, and Pt＋ Rh/Ce0.35Zr0.55Y0. 1O1.95＋Al2O3 was the best.

关 键 词：储氧材料 铈锆比 程序升温还原 三效催化剂 

分 类 号：O643.36[理学—物理化学]