ルイス・ベース・パッシベーションはペロフスキートヘテロジュンクションでの電荷移転を媒介する
Robert J E Westbrook1,2,3, Thomas J Macdonald1,3, Weidong Xu1,3
1Department of Chemistry, Imperial College London, Molecular Sciences Research Hub White City Campus, Wood Lane W12 0BZ, United Kingdom.
Journal of the American Chemical Society
|August 3, 2021
まとめ
負荷輸送層をペロブスキート欠陥部位に化学的に結合することは,効率的な負荷注入の鍵です. この受容媒介による電荷移転は,ペロブスキート太陽電池の穴収量と寿命を改善します.
科学分野:
- 材料科学
- 太陽光発電
- 化学工学
背景:
- ペロブスキート太陽電池の性能には 効率的なチャージ転送が不可欠です
- トラップ媒介による再結合と電荷輸送層 (CTL) への電荷注入を理解することは極めて重要です.
- 既存のモデルでは,インターフェースにおける化学結合の役割がしばしば見過ごされている.
研究 の 目的:
- 充電注入におけるCTLとペロブスキート欠陥部位間の化学結合の役割を調査する.
- n-i-p と p-i-n のペロブスキート太陽電池の構造におけるインターフェイスの電荷移転のメカニズムを解明する.
- 次の世代のCTLの設計ルールを確立する.
主な方法:
- 光学スペクトロスコピーとX線光電子スペクトロスコピー (XPS) の組み合わせを使用した.
- CTLとCH3NH3PbI3表面の間のルイス塩基相互作用を調査した.
- 束縛と電荷载体ダイナミクスを相関させるため,一時的吸収スペクトロスコーピー (TAS) を採用した.
主要な成果:
- CTLとCH3NH3PbI3の欠陥部位間の化学結合が充電注入に不可欠であることを実証した.
- 主要な結合メカニズムとしてルイス塩基相互作用を特定した.
- 結合の強化と注射孔の寿命の延長が相関する.
結論:
- パッシベーション媒介の電荷伝達は,一般的なペロブスキート太陽電池構成で発生する.
- インタフェースの化学結合は,電荷の注入効率に大きな影響を及ぼします.
- この発見は,ペロブスキート太陽電池の改良されたCTLを開発するための重要な設計原理を提供します.
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