Efficient bulk heterojunction (BHJ) photovoltaic cells (PVs) based on 5 wt. donors and C70 were fabricated. Tris[4-(5-phenylthiophen-2-yl) phenyl]-amine (TPTPA)-based BHJ PVs show higher power conversion efficiency (ηPCE) than aluminum phthalocyanine chloride-based BHJ PVs. Although the absorption of AlPcCl is complementary to that of C70, TPTPAs high hole mobility and symmetrical molecular structure are likely to be crucial contributing factors to the higher ηPCE. Phase separation occurs in the 5-TPTPA blend. The device was optimized via replacement of the bathocuproine buffer by a combination of 3,4,9,10-perylenetetracarboxylic bis-benzimidazole and bathocuproine. ηPCE of 5.96 is achieved because of the decreased series resistance.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)