摘要
采用柠檬酸溶胶凝胶法制备了一系列钇掺杂的富锆铈锆复合氧化物Ce0.33YxZr0.67-xO2,并通过XRD,BET,OSC,XPS,in-situ CO-FTIR等测试,系统研究了钇掺杂后铈锆复合氧化物储放氧性能的变化规律及其影响因素。结果表明,钇离子能够进入铈锆晶格形成固溶体,并提高铈锆体系的结构热稳定性。对于新鲜样,钇掺杂可大幅提升Ce0.33Zr0.67O2材料的比表面积,提高单位质量铈锆材料的储氧能力;但老化后,钇掺杂样品的储氧性能随着掺杂量的增加而减小。通过XPS及原位红外吸附性能测试证实,钇在Ce0.33Zr0.67O2材料表面主要取代锆离子,其掺杂会降低样品的表面吸附能力,抑制铈的氧化还原反应,从而导致该体系储氧性能的下降。
A series of Y-doped Ce0.33Zr0.67O2（CZ） materials were prepared by citric acid sol-gel method.The effects of yttrium on the oxygen storage capacities of Ce0.33Zr0.67O2 were studied by OSC measurement,XRD,BET,XPS,and in-situ CO-IR.The results revealed that Y could improve the structural thermal stability.For the fresh samples,the addition of Y enhanced the surface area,so as to improve the OSC value of the CZ.However,for the aged sample,the OSC decreased obviously with the increasing of Y doping ratio.Confirming by XPS and in-situ CO-FTIR,Y substituted the Zr sites on the surface of CZ.The doped Y ions had a counteractive to OSC because of reducing the adsorption properties of CZ and inhibiting the redox process of the Ce ions.
出处
《稀土》
EI
CAS
CSCD
北大核心
2012年第3期6-11,共6页
Chinese Rare Earths
基金
国家自然科学基金项目资助(50972069)
国家863计划课题资助(2009AA064803)
关键词
铈锆复合氧化物
富锆
钇掺杂
储氧性能
CeO2-ZrO2 mixed oxides
Zr-rich
yttrium doping
oxygen storage capacity
