リバーシブル [2 + 2] サイクルアドディションによる2Dと3Dの共性有機フレームワーク間の変換
Thaksen Jadhav1, Yuan Fang1, Cheng-Hao Liu1
1Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, Quebec H3A 0B8, Canada.
Journal of the American Chemical Society
|April 21, 2020
まとめ
研究者は2Dと3Dの共性有機フレームワーク (COF) の間の最初の可逆変換を達成しました. 光は3D COFにクロスリンクを誘発し,加熱はそれを逆転させ,材料の性質と伝導性を変化させます.
科学分野:
- 材料科学
- ポリマー化学
- クリスタルグラフィー
背景:
- 協和有機フレームワーク (COF) は調節可能な特性を提供しますが,その次元性を変換することは困難です.
- COFの次元性を制御すると,その機械的,電子的,伝導的行動に影響されます.
研究 の 目的:
- 2Dと3DのCOFの間の最初の変換を報告する.
- この変換の可逆性とその物質特性への影響を調査する.
主な方法:
- 2Dポリ (アリレンビニレン) COFの吸収エッジ照射で [2 + 2]サイクロアディションを誘導する.
- 熱処理 (200 °C) でサイクロレバーションを誘導し,2DCOFを回復する.
- 機械的,電子的,光学的および導電性特性の特徴
主要な成果:
- 2Dから3DのCOFに [2 + 2]サイクル添加による光誘発変換が成功しました.
- COFの結晶性を保ち,加熱によって達成される可逆変換.
- UV-Visの吸収,発光,帯状構造,酸ドーピング行動において顕著な変化が観察されました.
- 部屋温度のイオン伝導率 (2Dでは1.8 × 10−4 S/cm,3Dでは3.5 × 10−5 S/cm) と陽子伝導率 (2Dでは1.7 × 10−2 S/cm,3Dでは2.2 × 10−3 S/cm) を実証した.
結論:
- COFにおける次元変換は,可逆的な光と熱による反応によって達成可能である.
- この変換は,エネルギー貯蔵と電子機器における潜在的なアプリケーションのためにCOFの特性を調整するための新しい経路を提供します.
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