CAJ | 학술논문

CeO2因具有较高的储氧/释氧能力、较强的氧化-还原性能,受到人们极大关注,并在工业催化领域其有重要应用.杂质对CeO2性能具有重要影响,用基于密度泛函理论的第一性原理方法和具有三维周期性边界条件的超晶胞模型,计算并分析了金属Al掺杂对CeO2原子结构、电子结构和化学特性的影响.在计算中,用DFT+U方法描述Ce 4f电子的强关联效应,用基于GGA的PAW势描述芯电子与价电子的相互作用.计算结果表明,Al掺杂降低还原能,使形成氧空位更容易,并从原子结构和电子结构等方面对掺杂降低还原能的机理进行了分析.
CeO2인구유교고적저양/석양능력、교강적양화-환원성능,수도인문겁대관주,병재공업최화영역기유중요응용.잡질대CeO2성능구유중요영향,용기우밀도범함이론적제일성원리방법화구유삼유주기성변계조건적초정포모형,계산병분석료금속Al참잡대CeO2원자결구、전자결구화화학특성적영향.재계산중,용DFT+U방법묘술Ce 4f전자적강관련효응,용기우GGA적PAW세묘술심전자여개전자적상호작용.계산결과표명,Al참잡강저환원능,사형성양공위경용역,병종원자결구화전자결구등방면대참잡강저환원능적궤리진행료분석.
The geometric and electronic structures of the unreduced and reduced Al-doped ceria are systematically studied using the first principle method based on the density functional theory(DFT) within generalized gradient approximation(GGA) and with the inclusion of on-site Coulomb interaction(DFT+U). The projector-augmented wave method(PAW) is applied to treat the interaction of the core electrons with the valence electrons. It is shown that Al-doping substantially reduces the reduction energies, i. e. makes the reduction easier. The mechanisms that the Al dopant lowes the reduction energies are studied in detail from atomic and electronic structure analysis.