Enhancement of P3HT/PCBM photovoltaic efficiency using the surfactant of triblock copolymer containing poly(3-hexylthiophene) and poly(4- vinyltriphenylamine) segments
Journal
Macromolecules
Journal Volume
43
Journal Issue
14
Pages
6085-6091
Date Issued
2010
Author(s)
Abstract
In this study, the well-defined coil-rod-coil triblock copolymer poly(4-vinyltriphenylamine)-b-poly(3-hexylthiophene)-b-poly(4- vinyltriphenylamin) (PTPA-P3HT-PTPA) was used as a surfactant for P3HT/PCBM (1:1) based solar cells. The power conversion efficiency of the device was enhanced from 3.9 to 4.4% in the presence of the 0-5% PTPA-P3HT-PTPA under illumination of AM 1.5G (100 mW/cm2). The morphology variation and the balance of the hole/electron mobility accounted for such enhancement. In the P3HT/PCBM/PTPA-P3HT-PTPA ternary blends, the fiber-like structure was observed for surfactant ratios of 0-5%, while a sphere-like nanostructure was observed for the surfactant ratio of 1.5%. The sphere-like nanostructure led to a smaller domain size and enhanced interfacial area for charge separation as compared to the fiber-like structure. On the other hand, the increased hole mobility in the blend with the addition of PTPA-P3HT-PTPA resulted in the balanced hole and electron mobility (μe/μh ∼1.7 in comparison to the ratio of 3.6 without the surfactant). The incorporated PTPA-P3HT-PTPA surfactant not only extended the lifetime of solar cells but also reduced the PCBM aggregation upon annealing, resulting in better thermal stability. The DSC result confirmed the selective miscibility of the PTPA coil segment with PCBM. These results demonstrated the superior compatibilizing effect of the rod-coil triblock copolymers for solar cell applications. © 2010 American Chemical Society.
SDGs
Other Subjects
Charge separations; Coil segment; Domain size; Interfacial areas; Photo-voltaic efficiency; Poly (3-hexylthiophene); Power conversion efficiencies; Rod-coil; Solar-cell applications; Surfactant ratio; Ternary blends; Thermal stability; Triblock copolymers; Block copolymers; Conversion efficiency; Copolymerization; Electron mobility; Hole mobility; Nanostructures; Size separation; Solar cells; Spheres; Surface active agents
Type
journal article