ポリマー/フルレンの大量ヘテロ結合膜におけるゲミネート電荷再結合と太陽電池機能への影響
Suman Kalyan Pal1, Tero Kesti, Manisankar Maiti
1Chemical Physics, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
Journal of the American Chemical Society
|August 14, 2010
まとめ
ポリマー/フルレンの太陽電池の充電ダイナミクスにフルレンの誘導体がどのように影響するかを調査しました. 異なるデリバティブは,充電再結合率に影響を及ぼし,内部電気場は,デバイスにおける効率的な充電抽出に不可欠です.
科学分野:
- マテリアルサイエンス 材料科学
- フォトボルトイカは,太陽光発電です.
- オーガニック・エレクトロニクス
背景:
- ポリマー/フルレンの大量ヘテロジャンクション (BHJ) 太陽電池は,再生可能エネルギーにとって有望である.
- 充電生成と再結合のダイナミクスを理解することは,デバイスの効率を改善するための鍵です.
研究 の 目的:
- BHJの太陽電池における電荷生成と再結合に3つの異なるフルレン誘導体の影響を調査する.
- 充電ダイナミクスをフラーレンの誘導体と装置物理学の性質と相関させる.
主な方法:
- APFO3/フルレンBHJ混合物における電荷生成と再結合のダイナミクスを研究した.
- 電荷伝送率を分析し,それをLUMOのエネルギーと物質特性と相関させた.
主要な成果:
- 充電生成はAPFO3/[70]PCBMとAPFO3/[60]PCBMに類似したが,APFO3/[70]BTPFよりも遅かった.
- 双子の電荷再結合率は著しく変化し,APFO3/[70]PCBM < APFO3/[60]PCBM < APFO3/[70]BTPFの順番で増加しました.
- 観測された再結合率は,LUMOエネルギーだけでは説明できないため,電荷の移動性と分離距離の役割が示唆されています.
結論:
- ゲミナート再結合は,電荷分離距離と物質特有の電荷移動性に影響されます.
- BHJ太陽電池では,内部電場,極化,およびポラロンダイナミクスは,電子穴の引き寄せを克服し,効率的な電荷抽出を達成するために不可欠です.
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