酸アルミニウムシリケート水素の原子レベル構造
Aslam Kunhi Mohamed1,2, Pinelopi Moutzouri3, Pierrick Berruyer3
1Laboratory of Construction Materials, Institut des Matériaux, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
Journal of the American Chemical Society
|May 15, 2020
まとめ
シメント中のアルミニウム
科学分野:
- 材料科学
- 化学について
- 地化学
背景:
- カルシウムアルミニウムシリケート水素 (C-A-S-H) などの水素化製品におけるアルミニウムの役割は完全に理解されていません.
- C-A-S-H のアルミニウムの構造的性質は 長いセメント化学の謎でした
研究 の 目的:
- カルシウムアルミニウムシリケート水素 (C-A-S-H) の内部におけるアルミニウムの構造的組み込みと調整を明らかにする.
- "第3アルミ酸水素" (TAH) の存在と割り当てに関する議論を解決する.
主な方法:
- アルミニウムの構造的振る舞いを予測するために,最初の原理の計算が採用されました.
- 27Alと29Si NMRを含む高度な固体核磁気共振 (NMR) スペクトロスコーピーを用いて実験的検証を行った.
主要な成果:
- 最初の原理の計算では,シリケート鎖の橋渡し部位にアルミニウムの組み込みを予測し,Ca:SiとH2Oの高い比率で6倍調整しました.
- 27Alと29Siの実験的なNMRは,C-A-S-Hシリケートと相関するシリケート-ブリッジング [AlO2 (((OH)) 4-複合体の形成を確認した.
- これらの橋渡しアルミニウム部位に5ppmの狭い27Al NMR信号が割り当てられ,TAH段階には割り当てられませんでした.
結論:
- C-A-S-Hのアルミニウムは,カルシウムイオンによって安定したシリケートブリッジング [AlO2 (OH) ]4-複合体として存在します.
- "第3アルミ酸水素" (TAH) 段階は存在せず,セメント科学における重要な議論を解決した.
- この研究は,シメント水分化製品における6倍調整アルミニウムの構造的役割を明らかにする.
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