2025-11-12 大阪大学,科学技術振興機構
キラル物質を介したスピン制御を太陽電池に応用した初の実証例であり、レアメタルに頼らない柔軟・軽量な次世代エネルギーデバイス開発へ大きな一歩を示す成果である。
図 1 本研究の概要：CISS を示すキラル二面性非フラーレンアクセプターの合成と太陽電池への応用
＜関連情報＞
- https://www.jst.go.jp/pr/announce/20251112-2/index.html
- https://www.jst.go.jp/pr/announce/20251112-2/pdf/20251112-2.pdf
- https://onlinelibrary.wiley.com/doi/10.1002/anie.202518505
キラリティー誘起スピン選択性を有するキラル両面非フラーレンアクセプター：有機太陽電池の性能を向上させるホモキラル戦略 Chiral Bifacial Non-Fullerene Acceptors with Chirality-Induced Spin Selectivity: A Homochiral Strategy to Improve Organic Solar Cell Performance
Shuang Li, Prof. Dr. Fumitaka Ishiwari, Dr. Shaoxian Li, Prof. Dr. Yumi Yakiyama, Prof. Dr. Akinori Saeki
Angewandte Chemie International Edition Published: 10 November 2025
DOI:https://doi.org/10.1002/anie.202518505
Abstract
Asymmetric design has emerged as an effective strategy to enhance the performance of non-fullerene acceptors (NFAs) in organic solar cells (OSCs). Although most asymmetric NFAs focus on lateral (i.e., left–right) asymmetry, out-of-plane anisotropy has remained underexplored, despite its ability to induce both a vertical dipole moment and molecular chirality, thereby potentially enabling functionalities such as chirality-induced spin selectivity (CISS). With this perspective, we develop chiral and bifacial NFAs, (S,S)-IE4F, and (R,R)-IE4F, featuring an indacenodithiophene (IDT) core bearing a hydrophilic oligo(ethylene glycol) group and a hydrophobic phenyl group on the bridging sp3-carbons. Their racemic counterpart (rac-IE4F) and a non-bifacial achiral isomer (meso-IE4F) are also synthesized as the controls. Compared to meso-IE4F, the bifacial isomers exhibit higher solubility, more favorable molecular packing for carrier transport, and larger dipole moments. Notably, neat (S,S)/(R,R)-IE4Fs and their bulk heterojunctions with PBDB-T exhibit pronounced CISS effect, with spin polarizations of ∼70% and ∼50%, respectively. Consequently, OSCs based on homochiral bifacial IE4Fs achieve a power conversion efficiency of 8.17%, three times higher than that of meso-IE4F. This study highlights the impact of isomerization in NFAs and provides a new molecular design strategy for homochiral asymmetric NFAs.
