Synthesis of 3H-Benzo[e]indoline and Its Application to Small-Molecule Organic Solar Cells

A squaraine-based small molecule (USQ-BI) bearing 3H-benzo[e]indoline was synthesized as an electron donor, and the corresponding organic solar cells show power conversion efficiency of 5.35% with an excellent short circuit current of over 15mAcm(-2). The hole mobility of USQ-BI was about 5 times (9.57x10(-5) vs. 2.00x10(-5)cm(2)V(-1)s(-1)) higher than that of indoline-based squaraine.