Understanding All-Solid Frustrated-Lewis-Pair Sites on CeO2 from Theoretical Perspectives
Understanding All-Solid Frustrated-Lewis-Pair Sites on CeO2 from Theoretical Perspectives
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从理论角度理解 CeO2 上的全固态受阻刘易斯对位点
DOI：
10.1021/acscatal.7b02732
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发表时间：
2018-01-01
期刊：
影响因子：
12.9
通讯作者：
Chang, Chun-Ran
中科院分区：
文献类型：
--
作者：
Huang, Zheng-Qing;Liu, Li-Ping;Chang, Chun-Ran
从均相阻挫路易斯对（FLP）概念发展到非均相阻挫路易斯对（FLP）催化剂在实际应用中具有很大的前景。虽然我们最近的发现已经表明，可以通过表面氧空位调节在二氧化铈上产生全固体FLP（Zhang等人，Nat. Commun. 2017，8，15266），仍然期望对固体FLP的固有性质和反应性的合理理解。本文利用密度泛函理论计算对CeO 2（110）和（100）表面上构建的FLP（Ce···O）进行了全面的理论研究。我们发现，表面氧空位的产生可以增强FLP-酸位的酸性和FLP-碱位的碱性。刘易斯中心酸碱性的增强以及刘易斯对（Ce···O）间距的延长是导致固体FLP高活性的原因。H2在FLP上的解离活化经历了一个异裂途径（H2 → Hδ+ + Hδ−），在CeO 2（110）上的活化能为0.07 eV，在CeO 2（110）上的活化能为0.0 eV。
The development of heterogeneous frustrated-Lewis-pair (FLP) catalysts from homogeneous FLP conception is of great promise in practical applications. While our recent discovery has shown that all-solid FLPs can be created on ceria via surface oxygen vacancy regulation (Zhang et al. Nat. Commun. 2017, 8, 15266), a sound understanding of the intrinsic property and reactivity of the solid FLPs is still expected. Here we present a comprehensive theoretical study on the FLPs (Ce···O) constructed on CeO2(110) and (100) surfaces by using density functional theory calculations. We find that the creation of surface oxygen vacancy can enhance both the acidity of FLP-acid site and the basicity of FLP-base site. The enhanced acidity and basicity of Lewis sites together with the elongated distance of Lewis pairs (Ce···O) contribute to the high activity of solid FLPs. The dissociative activation of H2 on FLPs experiences a heterolytic pathway (H2 → Hδ+ + Hδ−) with a low activation energy of 0.07 eV on CeO2(110) and 0.0...