メタル・オーガニック・フレームワークにおける熱膨張の調整
Samuel J Baxter1, Andreas Schneemann1, Austin D Ready1
1Sandia National Laboratory , Livermore , California 94550 , United States.
Journal of the American Chemical Society
|July 20, 2019
まとめ
研究者は,金属有機フレームワーク (MOF) の負から正の熱膨張の継続的な調節を実現し,固体溶液を作成しました. この突破はMOFの熱特性に対する新しい制御を提供します.
科学分野:
- 材料科学
- 化学について
- 固体物理学
背景:
- メタル・オーガニック・フレームワーク (MOF) は,負の熱膨張 (NTE) を示すことが知られている.
- 一つのMOFフェーズで熱膨張をネガティブからポジティブに継続的に調整することはこれまで報告されていません.
- 伝統的なNTE材料にはこの調節可能な特性がない.
研究 の 目的:
- MOFシステムにおける熱膨張の継続的なチューニングを調査する.
- 熱膨張を制御するための単相固体溶液の形成を調査する.
- MOFにおける熱膨張の調整のための一般的な戦略を確立する.
主な方法:
- Zn-DMOF-TMシステムで一連の混合リンカー固体溶液の合成.
- 合成されたMOFの熱膨張特性の特徴.
- 熱膨張行動に影響を与える構造変化の分析.
主要な成果:
- ネガティブからプラスの熱膨張へのスムーズな移行は,四角形の材料のa-b平面で観察されました.
- 熱膨張ゼロの温度は,TM-bdc含有量が増加するにつれて~186Kから~325Kに変化した.
- 単相固体溶液の成功形成により,継続的な熱膨張チューニングが可能になった.
結論:
- 混合リンク器の固体溶液は,MOFの熱膨張を制御するための実行可能で一般的な戦略です.
- この研究は,単一のMOFシステムにおける熱膨張の前例のない調整性を示しています.
- この発見は,特定の熱膨張特性を持つMOFの設計のための道を開く.
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