亜鉛改性シリケート水素の原子レベル構造
Anna Morales-Melgares1,2, Ziga Casar2, Pinelopi Moutzouri1
1Laboratory of Magnetic Resonance, Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015Lausanne, Switzerland.
Journal of the American Chemical Society
|December 12, 2022
まとめ
トリカルシウムシリケート (C3S) に亜鉛を加えると,機械的強度が向上する. 亜鉛は,シリコン部位を置換し,鎖の長さを増加させ,セメントの性質を向上させ,カルシウムシリケート水素 (C-S-H) の構造を変更する.
科学分野:
- 材料科学
- 化学について
- 固体物理学
背景:
- トリカルシウムシリケート (C3S) の機械的強度は,水分化の際に亜鉛を加えることで強化される.
- 主要な水素化製品である亜鉛改性カルシウムシリケート水素 (C-S-H) の原子レベル構造は十分に理解されていません.
研究 の 目的:
- 亜鉛改性カルシウムシリケート水素 (C-S-H) の原子構造を解明する.
- C-S-H構造における亜鉛置換の役割とそのシリケート鎖の長さに与える影響を調査する.
主な方法:
- 29Si DNP強化の固体核磁気共振 (NMR) スペクトロスコーピーを利用した.
- 化学シフト計算に密度関数理論 (DFT) を採用した.
- 原子構造を決定するための応用分子動力学 (MD) モデリング.
主要な成果:
- 特定したシリコン部位で亜鉛の置換を示唆する2つの新しいシリコン種 (Q(1,Zn) とQ(2p,Zn) を特定した.
- ダイマー (Q ((1)) とブリッジング (Q ((2b)) のシリコン環境における亜鉛置換が観察された.
- 亜鉛の含有量の増加は,C-S-Hの平均鎖の長さを促進することを示した.
結論:
- 亜鉛改性C-S-Hの原子構造が決定された.
- 亜鉛の組み込みは,シリコンを代用し,シリケート鎖のポリメリゼーションを増やすことで,C-S-H構造を変更する.
- これらの構造改変は,亜鉛改性セメントの強化された機械的特性についての洞察を提供します.
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