標題: | Tunable Novel Cyclopentadithiophene-Based Copolymers Containing Various Numbers of Bithiazole and Thienyl Units for Organic Photovoltaic Cell Applications |
作者: | Li, Kuang-Chieh Huang, Jen-Hsien Hsu, Ying-Chan Huang, Po-Ju Chu, Chih-Wei Lin, Jiann-T'suen Ho, Kuo-Chuan Wei, Kung-Hwa Lin, Hong-Cheu 材料科學與工程學系 光電工程學系 Department of Materials Science and Engineering Department of Photonics |
公開日期: | 9-六月-2009 |
摘要: | Six novel conjugated copolymers (P1-P6) containing coplanar cyclopentadithiophene (CPDT) units (incorporated with bithiazole/thienyl-based monomers) were synthesized and developed for the applications of polymer solar cells (PSCs). Copolymers P1-P6 covered broad absorption ranges from UV to near-infrared (400-800 nm) with narrow optical band gaps of 1.70-1.94 eV, which are compatible with the maximum solar photon reflux. Partially reversible p- and n-doping processes of P1-P6 in electrochemical experiments were observed. Compared with those previously reported CPDT-based narrow band gap polymers, the proper molecular design for HOMO/LUMO levels of P1-P6 induced relatively high photovoltaic open-circuit voltages in the PSC devices. Powder X-ray diffraction (XRD) analyses suggested that these copolymers formed highly self-assembled pi-pi stackings. Under 100 mW/cm(2) of AM 1.5 white-light illumination, bulk heterojunction PSC devices containing an active layer of electron donor copolymers P1-P6 blended with electron acceptor [6,6]-phenyl C(61) butyric acid methyl ester (PCBM) in the weight ratio of 1:1 were explored, and the external quantum efficiency (EQE) measurements showed a maximal quantum efficiency of 60%. The PSC device containing P4 in the weight ratio of 1:2 with PCBM gave the best preliminary result with an overall power conversion efficiency (PCE) of 3.04%, an open-circuit voltage of 0.70 V, a short-circuit current of 8.00 mA/cm(2), and a fill factor of 53.7%. |
URI: | http://dx.doi.org/10.1021/ma900416d http://hdl.handle.net/11536/7121 |
ISSN: | 0024-9297 |
DOI: | 10.1021/ma900416d |
期刊: | MACROMOLECULES |
Volume: | 42 |
Issue: | 11 |
起始頁: | 3681 |
結束頁: | 3693 |
顯示於類別: | 期刊論文 |