Modeling surface spin polarization on ceria-supported Pt nanoparticles
Modeling surface spin polarization on ceria-supported Pt nanoparticles
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DOI：
10.1088/1361-648x/ac62a3
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发表时间：
2021-10
期刊：
影响因子：
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通讯作者：
B. Kang;Joshua L. Vincent;Yongbin Lee;L. Ke;P. Crozier;Qian Zhu
中科院分区：
文献类型：
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作者：
B. Kang;Joshua L. Vincent;Yongbin Lee;L. Ke;P. Crozier;Qian Zhu
在这项工作中，我们采用密度泛函理论模拟研究可能的CeO 2-（111）表面的自旋极化及其对氧化铈载体和Pt纳米颗粒之间的相互作用的影响。在高斯型轨道基础上，我们的模拟表明，由于原子Ce和O层之间的内部电荷转移，CeO 2-（111）表面表现出强大的表面自旋极化。降低了表面氧空位的形成能，提高了氧化物的还原性。我们发现，列入自旋极化可以显着降低主要的活化势垒在建议的反应途径的CO氧化铈支持的Pt纳米粒子。对于金属-载体相互作用，表面自旋极化增强了Pt纳米颗粒和氧化铈表面氧之间的键合，而CO吸附在Pt纳米颗粒上减弱了界面相互作用，而不管自旋极化如何。然而，稳定的表面自旋极化只能在基于高斯型轨道基的模拟中找到。鉴于未来高性能催化剂设计的潜在重要性，我们目前的研究表明，迫切需要在实验和理论上研究过渡金属氧化物的表面铁磁性。
In this work, we employ density functional theory simulations to investigate possible spin polarization of CeO2-(111) surface and its impact on the interactions between a ceria support and Pt nanoparticles. With a Gaussian type orbital basis, our simulations suggest that the CeO2-(111) surface exhibits a robust surface spin polarization due to the internal charge transfer between atomic Ce and O layers. In turn, it can lower the surface oxygen vacancy formation energy and enhance the oxide reducibility. We show that the inclusion of spin polarization can significantly reduce the major activation barrier in the proposed reaction pathway of CO oxidation on ceria-supported Pt nanoparticles. For metal-support interactions, surface spin polarization enhances the bonding between Pt nanoparticles and ceria surface oxygen, while CO adsorption on Pt nanoparticles weakens the interfacial interaction regardless of spin polarization. However, the stable surface spin polarization can only be found in the simulations based on the Gaussian type orbital basis. Given the potential importance in the design of future high-performance catalysts, our present study suggests a pressing need to examine the surface ferromagnetism of transition metal oxides in both experiment and theory.