Aqueous medium induced optical transitions in cerium oxide nanoparticles
Talgat M Inerbaev1, Ajay S Karakoti, Satyanarayana V N T Kuchibhatla
1Gumilyov Eurasian National University, Astana, 010008, Republic of Kazakhstan.
Physical Chemistry Chemical Physics : PCCP
|February 7, 2015
Summary
Water molecules significantly alter the optical properties of nanoceria, causing shifts in light absorption. This study reveals how water
Area of Science:
- Materials Science
- Nanotechnology
- Physical Chemistry
Background:
- Nanoceria exhibits unique optical properties influenced by cerium oxidation states.
- Understanding the interaction of nanoceria with its environment is crucial for applications.
Purpose of the Study:
- To investigate the impact of water on the optical properties of nanoceria.
- To determine the influence of Ce(3+) concentration on these optical changes.
Main Methods:
- Experimental measurements of optical properties.
- Theoretical calculations using density functional plane-wave methods.
- Modeling nanoceria with adsorbed water molecules.
Main Results:
- Indirect optical transitions in bare nanoceria red-shift with increasing Ce(3+).
- Adsorbed water induces a blue shift in indirect optical transitions.
- Direct optical transitions blue-shift in aqueous environments.
- Theoretical and experimental results show consistent shifts.
Conclusions:
- Water molecules' polarization effect on f-electron states drives the observed optical shifts.
- Environmental factors like water significantly modify nanoceria's optical behavior.
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