Electron microscopy investigations of the organization of cerium oxide nanocrystallites and polymers developed in polyvinylpyrrolidone-assisted polyol synthesis process
Abstract
The microstructures and the organization mechanism of cerium oxide (ceria) nanospheres were investigated by transmission electron microscopy. The ceria nanospheres with the diameter of 50-150 nm were produced by the polyol synthesis method with cerium nitrate precursor and with polyvinylpyrrolidone (PVP) used as a protecting agent. Dose-limited observations performed by energy-filtering transmission electron microscopy revealed that the ceria nanospheres were the aggregated products consisting of ceria nanocrystallites 3 nm in size and PVP-derived polymer products. It was found that the ceria nanocrystallites were oriented within the nanospheres by high-resolution transmission electron microscopy and selected-area electron diffraction. Selective adsorption of PVP on the crystal facets of the ceria nanocrystallites was suggested, and the aggregation of the PVP-adsorbed ceria through cross-linking reaction of PVP causes the crystal orientation.
- Publication:
-
Journal of Nanoparticle Research
- Pub Date:
- March 2012
- DOI:
- 10.1007/s11051-012-0734-7
- Bibcode:
- 2012JNR....14..734H
- Keywords:
-
- Ceria nanoparticles;
- Polyol synthesis method;
- Energy-filtering TEM;
- High-resolution TEM;
- Selected-area electron diffraction;
- Polyvinylpyrrolidone