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DOE OSTI · 2434273

Observing the Surface Termination of LaScO 3 Perovskite Using Solid-State Nuclear Magnetic Resonance

Zhao, Tommy Yunpu·Greenstein, Emily P.·Peczak, Ian L.·Poeppelmeier, Kenneth R.·Perras, Frédéric A.
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Abstract

Materials with well-defined surfaces are drawing increased attention for the design of bespoke catalysts and nanomaterials. Gaining a detailed understanding of the surfaces of these materials is an important challenge, which is often complicated by surface polymorphism and dynamic restructuring. We introduce the use of surface-enhanced NMR spectroscopy for the observation of such surfaces, focusing on LaScO 3 as an example. Here, we show that double-resonance NMR experiments correlating surface oxygen and probe molecules to the 139 La and 45 Sc nuclei at the surface reveal the material to be terminated by a ScO x monolayer. Surface-selective 17 O and 45 Sc NMR experiments further showed the material to be hydroxyl terminated and that the surface may be prone to dynamic restructuring as a result of moisture exposure. Perhaps most interestingly, surface-selective 139 La NMR experiments revealed the existence of previously undetected surface lanthanum defects, suggesting that surface-enhanced NMR may be useful as a guide in the synthesis of defect-free surfaces in the design of various nanomaterials.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYMaterialsMolecular propertiesNanoparticlesNuclear magnetic resonance spectroscopyPolarization

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Zhao, Tommy Yunpu, Greenstein, Emily P., Peczak, Ian L., Poeppelmeier, Kenneth R., Perras, Frédéric A.. 2024-08-07. Observing the Surface Termination of LaScO 3 Perovskite Using Solid-State Nuclear Magnetic Resonance. https://doi.org/10.1021/jacs.4c07055

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