초록 |
The blends of polymer donor (PD) and small-molecule-acceptor (SMA) have achieved highly-efficient polymer solar cells (PSCs). However, most of the efficient PSCs are processed by toxic halogenated solvents. Here, we develop a new series of PDs by incorporating a hydrophilic flexible spacer (FS), and demonstrate efficient PSCs with a high power conversion efficiency (PCE) of 17.74% processed by hydrocarbon-solvent (toluene) process. The FS alleviates excessive backbone rigidity of the PDs, while retaining sufficient aggregation of the PDs toluene. Also, the FS enhances PD/SMA interfacial interactions and improve the blend morphology, affording efficient charge generation and mechanical stress dissipation. Therefore, the resulting PSCs with FS incorporated PD showed superior PCE (17.74%) and crack-onset strain (10.50%) values, outperforming the PSCs without the FS (PCE = 15.7% and COS = 2.99%). |