1. Rapid Synthesis and Sintering of La 2 O 2 S and Its Physical, Optical, and Mechanical Properties.
- Author
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Chen, Yuqi, Li, Liang, Li, Jin, and Han, Kun
- Subjects
DEBYE temperatures ,CERAMIC materials ,SPECIFIC gravity ,LATTICE constants ,RAMAN spectroscopy - Abstract
Rare-earth oxysulfides are a class of functional ceramic materials with excellent physico-chemical properties and rich functionality. In this study, La
2 O2 S powders were prepared from La2 S3 and La2 O3 powders at 1000 °C by pressureless sintering. La2 O2 S compacts were synthesized from La2 S3 and La2 O3 powders at 800–1600 °C by spark plasma sintering. The influences of sintering temperature and time on the preparation of La2 O2 S were studied. XRD results indicated that La2 O2 S ceramics were synthesized successfully and that the lattice constants of La2 O2 S were close to the theoretical values. SEM showed that the microstructure of La2 O2 S compacts was homogeneous. The specific heat of La2 O2 S mainly came from lattice contribution, and its Debye temperature was 237 K. The UV–visible absorption spectra showed different absorption levels in the 240–300 nm range. Raman spectroscopy revealed distinct peaks at different temperatures, indicating changes in the covalence band. The relative density of La2 O2 S ceramics was 92% and lower than theoretical values. Hardness of the synthesized La2 O2 S was greater than that of Gd2 O2 S ceramics. [ABSTRACT FROM AUTHOR]- Published
- 2024
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