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Catalytic Scavenging of Plant Reactive Oxygen Species In Vivo by Anionic Cerium Oxide Nanoparticles
Published on: August 26, 2018
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Contraction, cation oxidation state and size effects in cerium oxide nanoparticles
Jacopo Stefano Pelli Cresi1,2, Maria Chiara Spadaro1,2,3, Sergio D'Addato1,2
1Dipartimento di Scienze Fisiche Informatiche e Matematiche, Università degli Studi di Modena e Reggio Emilia, Via G. Campi 213/a, I-41125, Modena, Italy.
Nanotechnology
|October 11, 2017
Summary
Researchers studied cerium oxide nanoparticles (NPs) to understand their structure. Smaller NPs show a contracted Ce-O distance due to reduced dimensionality, impacting their properties.
Area of Science:
- Materials Science
- Nanotechnology
- Solid State Chemistry
Background:
- Understanding cerium oxide nanoparticle (NP) structure is crucial for their applications.
- Local atomic structure, oxidation state, and defectivity influence NP functionality.
Purpose of the Study:
- Investigate the relationship between size, local atomic structure, oxidation state, and defectivity in cerium oxide NPs.
- Determine how structural modifications affect NP properties.
Main Methods:
- X-ray absorption fine structure (XAFS) analysis (near and extended energy range).
- High-resolution transmission electron microscopy (HRTEM) for morphology and crystalline quality.
- Preparation of cerium oxide NPs with variable diameters (<10 nm) via physical methods.
Main Results:
- Demonstrated a progressive contraction of the Ce-O interatomic distance with decreasing NP diameter.
- Attributed the contraction to reduced dimensionality.
- Observed that a 4%-6% increase in Ce3+ concentration did not significantly alter the contraction.
Conclusions:
- The size-dependent contraction of the Ce-O bond in cerium oxide NPs is a key structural feature.
- This contraction, linked to reduced dimensionality, has implications for NP properties.
- Further investigation into the consequences of this structural change is warranted.
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