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Published on: September 19, 2020
Synthesis of crystalline skutterudite superlattices using the modulated elemental reactant method
Joshua R Williams1, Arwyn L E Smalley, Heike Sellinschegg
1Department of Chemistry and Material Science Institute, University of Oregon, Eugene, Oregon 97403, USA.
Journal of the American Chemical Society
|August 21, 2003
Summary
Researchers created novel skutterudite superlattices by annealing layered films. Short repeat units formed skutterudites, while long repeat periods persisted, revealing new superlattice structures.
Area of Science:
- Materials Science
- Solid-State Chemistry
Background:
- Skutterudites (M(4)Sb(12)) are promising thermoelectric materials.
- Superlattices offer tunable properties through layered structures.
Purpose of the Study:
- To synthesize and characterize skutterudite superlattices with controlled compositions.
- To investigate the structural evolution of layered films upon annealing.
Main Methods:
- Preparation of ((AB)(x)(CD)(y))(z) samples with varying repeat units.
- X-ray diffraction and reflectivity analysis to monitor structural changes.
- Annealing at different temperatures and times.
Main Results:
- Amorphous layered films transformed into crystalline skutterudite superlattices.
- Short repeat units interdiffused and formed skutterudites (M = Fe, Co, Ir).
- Long repeat periods remained intact after annealing, forming a persistent superlattice structure.
- Skutterudites crystallized with random crystallographic orientation.
- A novel superlattice structure was observed in IrSb(3)/CoSb(3) samples.
Conclusions:
- Successful synthesis of skutterudite superlattices with preserved long-periodicity.
- Demonstration of a new superlattice structure with potential for advanced materials applications.
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