ポリマーにおけるポリマーエネルギー環境の特徴: 純相および混合相を持つフルレンの大量ヘテロ結合
Sean Sweetnam1, Kenneth R Graham, Guy O Ngongang Ndjawa
1Materials Science and Engineering Department, Stanford University , Stanford, California 94305-4034, United States.
Journal of the American Chemical Society
|September 6, 2014
まとめ
ポリマー太陽電池 (PSC) のエネルギーオフセットは,電荷分離を強化することによって性能を改善します. この研究は,ポリマー形態学と分子間相互作用からのエネルギーシフトを定量化し,PSC効率の最適化に不可欠です.
科学分野:
- マテリアルサイエンス 材料科学
- オーガニック・エレクトロニクス
- フォトボルトイカは,太陽光発電です.
背景:
- ポリマーにおけるエネルギーオフセット:フルレンの大量ヘテロ結合は,電荷分離を改善し,ポリマー太陽電池 (PSC) の再結合を減らすために理論化されている.
- これらのエネルギーレベルの違いを理解することは,PSCのパフォーマンスを向上させるために非常に重要です.
研究 の 目的:
- ポリマーのポリマーフェーズにおける穴のエネルギーレベルを特徴付けるには,フルレンの散発ヘテロ結合.
- 異なる形態学的相と分子間相互作用から生じるエネルギーのオフセットを定量化するために.
主な方法:
- サイクルボルトメトリー (Cyclic Voltmetry) とは
- UV-VIS吸収スペクトロスコピー
- 紫外線光電子スペクトロスコーピー (UPS)
主要な成果:
- ポリマーの無形と結晶の相の間に最大150meVのエネルギーオフセットが観察され,ポリマーの結合長さの変化に起因する.
- ポリマー:フルレレンの分子間相互作用による最大350meVのエネルギーオフセットが特定され,これはしばしば見過ごされる要因です.
- 分子間相互作用が,いくつかのシステムにおける形態学的変化よりも大きなエネルギーシフトを誘導することが示された.
結論:
- エネルギーレベルの変化,特に分子間相互作用による変化は,PSCの性能に大きな影響を与えます.
- これらのエネルギーレベルの変化を徹底的に特徴づけることは,PSC機能の包括的な理解と将来のデバイスの最適化にとって不可欠です.
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