Synthesis of a Se0/Calcite Composite Using Hydrothermal Carbonation of Ca(OH)2 Coupled to a Complex Selenocystine Fragmentation

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• 作者：G. Montes-Hernandez ; A. Ferna&#x301 ; ndez-Marti&#x301 ; nez ; L. Charlet ; F. Renard ; A. C. Scheinost ; M. Bueno
• 刊名：Crystal Growth & Design
• 出版年：2008
• 出版时间：July 2008
• 年：2008
• 卷：8
• 期：7
• 页码：2497 - 2504
• 全文大小：2534K
• 年卷期：v.8,no.7(July 2008)
• ISSN：1528-7505

文摘

Elemental selenium (Se⁰)/calcite composites were synthesized in a batch system by hydrothermal carbonation of calcium hydroxide under high CO₂−Ar pressure (90 bar) and high temperature (90 °C) coupled to a complex selenocystine fragmentation. Under O₂-poor conditions, the composite consisted predominantly of spherical, amorphous nanoparticles of elemental red selenium (<500 nm) deposited on the calcite matrix. Conversely, under O₂-rich conditions, the composite consisted rod-shaped, well-crystallized microparticles of elemental gray selenium (<25 µm) dispersed in the calcite matrix. The carbonate matrix was constituted by nano- to microrhombohedral crystals (<2 µm) and micrometric agglomerates and/or aggregates (<5 µm). Our results present a new synthesis path to Se⁰/calcite composites, with spherical or rod-shaped Se⁰ morphology with high potential for medical (e.g., dietary supplement) or industrial (e.g., pigments) applications. Furthermore, this study may have implications in the field of biomineralization.