拡張型チエノキノイドを持つ非常に小さなバンドギャップπ結合ポリマー
Kohsuke Kawabata1, Masahiko Saito1, Itaru Osaka1
1Emergent Molecular Function Research Group, Center for Emergent Matter Science, RIKEN , Wako, Saitama 351-0198, Japan.
Journal of the American Chemical Society
|May 26, 2016
まとめ
キノイド性を持つ新しいπ結合ポリマーが合成され,電子欠乏単位としてチエノキノイドが特徴付けられました. PBDTD4Tは,非常に小さな帯域差 (0.88 eV) と二極電荷伝送を達成し,有機電子には有望である.
科学分野:
- 材料科学
- オーガニック電子
- ポリマー化学
背景:
- π結合ポリマーのバンドギャップの縮小は,有機電子機器における性能の向上に不可欠です.
- 帯域間隔の縮小のための効果的な戦略は,キノイドの性質を組み込むことです.
研究 の 目的:
- 強い電子欠乏型チエノキノイド単位を持つ新しいπ結合ポリマーを合成する.
- チエノキノイド (2,2'-ビチオフェン-5,5'-ダイオン,BTD) とベンゾジチオフェンディオン (ベンゾ[1,2-b:4,5-b']ディチオフェン-2,6-ダイオン,BDTD) 単体のポリマー特性に対する影響を調査する.
- 合成されたポリマーの電荷輸送特性と光学特性を評価する.
主な方法:
- 新しいπ結合ポリマーであるPBTD4TとPBDTD4Tを合成し,BTDとBTD受容体を組み込む.
- LUMOエネルギーレベル,バンドギャップ,透明性を含むポリマーの特性.
- 電荷輸送特性,特に穴と電子の移動性を評価する.
主要な成果:
- PBTD4Tは -3.77 eVのLUMOと1.28 eVのバンドギャップを示した.
- PBDTD4Tは -4. 04 eVのより深いLUMOと,0. 88 eVのより小さなバンドギャップを示し,高い可視透明性を示した.
- PBTD4TとPBDTD4Tは,バランスのとれた両極電荷輸送を示し,基準ポリマー (PTTD4T) を上回った.
結論:
- BDTDユニットの組み込みは,バンドギャップを大幅に削減し,近赤外線活動を強化します.
- 合成されたポリマーはバランスのとれた両極電荷輸送特性を示しています.
- これらのπ結合ポリマーは次世代の有機電子機器の製造に適しています.
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