ペンダントアゾベンゼン群の結晶ナノチャネル:ガス吸収と拡散に対するステリックまたは極性効果?

Hubiao Huang¹, Hiroshi Sato¹, Takuzo Aida^1,2

¹Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.

Journal of the American Chemical Society

|June 22, 2017

まとめ

この研究は,アゾベンゼンを含む金属有機フレーム (AzoMOF) がCO2吸収を制御できることを示しています. CO2の拡散と吸収に影響を及ぼします.

科学分野:

材料科学
化学工学
ナノテクノロジー

背景:

メタル・オーガニック・フレームワーク (MOF) は,ガス吸収のための調整可能な多孔構造を提供します.
アゾベンゼンベースのMOF (アゾMOF) は,フレームの特性に対する光反応制御を可能にします.

研究の目的:

ジルコニウムベースのMOFにおけるCO2吸収に対するアゾベンゼンイソメリゼーションの影響を調査する.
AzoMOFナノチャネル内のCO2相互作用を制御するメカニズムを解明する.

主な方法:

紫外線と可視光を用いたAzoMOFにおけるアゾベンゼン単体の光異体化.
異なるシス同位体含有量でのCO2とArによるガス吸収実験.
エリトロシンB染料を用いた極性探査

主要な成果:

紫外線照射で誘発されたトランス・トゥ・シス・イソメリゼーション (最大21%),CO2吸収を減少させる.
可視光または加熱による逆同化により,CO2吸収能力が回復する.
Ar吸収試験で示されたように,ステリック障害ではなく,CO2吸収が有意に影響された.

結論:

アゾベンゼン光異性化によって調節されるAzoMOFの内部極性は,CO2吸収の重要な要因である.
この光反応性MOFは,調整可能なCO2キャプチャアプリケーションの可能性を証明しています.

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