title: Enhancement of the Fill Factor through an Increase of the Crystallinity in Fullerene-Based Small-Molecule Organic Photovoltaic Cells.
abstract: We report that the crystallinity of C70 is improved significantly if CuI is used as a templating layer, leading to remarkable enhancement of hole mobilities from 8.32 × 10(-6) to 3.26 × 10(-5) cm(2)/(V s). As a result, the use of the templating layer in C70-based solar cells with low donor concentration resulted in significant improvement of the fill factor from 0.51 to 0.57 and the power conversion efficiency from 5.56% to 6.23% under simulated AM 1.5G, 1 sun irradiation. This result demonstrates that the CuI templating layer is effective at improving the crystallinity of the fullerene derivatives as well as the donor materials.
authors: †Department of Materials Science and Engineering, Seoul National University, Seoul 151-744, South Korea.
authors: Min-Soo
authors: MS
authors: Choi
authors: †Department of Materials Science and Engineering, Seoul National University, Seoul 151-744, South Korea.
authors: Tae-Min
authors: TM
authors: Kim
authors: †Department of Materials Science and Engineering, Seoul National University, Seoul 151-744, South Korea.
authors: Hyun-Sub
authors: HS
authors: Shim
authors: †Department of Materials Science and Engineering, Seoul National University, Seoul 151-744, South Korea.
authors: Beom-Soo
authors: BS
authors: Kim
authors: ‡Department of Organic Material Science and Engineering, College of Engineering, Pusan National University, Busan 609-735, South Korea.
authors: Hyo Jung
authors: HJ
authors: Kim
authors: †Department of Materials Science and Engineering, Seoul National University, Seoul 151-744, South Korea.
authors: Jang-Joo
authors: JJ
authors: Kim
keywords: C70; copper iodide; low donor concentration; organic photovoltaic; templating layer