合成,結晶構造,およびMg (x) B50C8またはMg (x) B12) 4CBC (x=2.4-4) の性質について
Volker Adasch1, Melanie Schroeder, Dominik Kotzott
1DRONCO AG, Wiesenmühle 1, D-95632 Wunsiedel, Germany.
Journal of the American Chemical Society
|September 16, 2010
まとめ
新しいボリウムマグネシウム炭化水素の結晶,Mg{x}B{50}C{8}は,ボロン炭化水素を上回る特殊な硬さを示しています. ボロン・イコサヘドラと炭素単位からなる構造は,鮮やかな色彩と電子特性を説明する.
科学分野:
- 固体化学 固体化学
- マテリアルサイエンス 材料科学
- 無機化学 無機化学とは
背景:
- ボリード炭化物は,耐火材料の重要なクラスである.
- 新型ボリド炭化物における構造-特性関係を理解することは,先進的な材料の開発に不可欠です.
研究 の 目的:
- 新しいマグネシウムボリドカルバイド,Mg(x) B(50) C(8) を合成し,特徴づけました.
- この新しい材料の構造,電子,機械的性質を調査する.
主な方法:
- 金属の溶融における元素前体から単結晶合成.
- シングルクリスタルX線 difrractionと電子マイクロプローブ分析を用いた特徴付け.
- 振動および光学スペクトルスコピー,マイクロ硬性試験 (ビッカースとノップ).
主要な成果:
- 変化するMg含量 (x = 2.4-4) を有するMg(x) B(50) C(8) の結晶の合成が成功しました.
- 好ましい組成はMg∼3) B∼50) C∼8) で,B∼12) のイコサヘドラとCを含む単位からなる3D共振ネットワークを特徴としています.
- 注目すべき高マイクロ硬度値 (H(V) ≈32 GPa,H(K) ≈31.5 GPa),ボロンカルバイド (B(4) C) を上回っている.
- 光学スペクトルは,観測された透明色と一致する2.7 eVのバンドギャップを明らかにします.
結論:
- Mg ((x) B ((50) C ((8)) の構造が解明され,その安定性と性質が説明される.
- この材料は優れた硬さを示し,厳しい環境での潜在的な応用を示しています.
- 電子構造はイオンモデルをサポートし,組成,色,バンドギャップを相関させる.
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