| 초록 |
The effects of substitute sulfur unit on optical and electrical properties of low-band-gap conjugated copolymers were investigated using poly[9-(bis-(octylthio)methylene)-2,7-fluorene-alt-5,5-(4’,7’-di-2-thienyl-5’,6’-dialkoxy-2’,1’,3’-benzothiadia-zole) (PTMFDTBT#1). The introduced sulfur atom on the alkyl chain at the position of fluorene moiety poly[9,9-dioctyl-2,7-fluorene-alt-5,5-(4’,7’-di-2-thienyl-5’,6’-dialkoxy-2’,1’,3’-benzothiadia-zole)] (PF8DTBT#2) of the intrinsic properties of the copolymers was significantly altered to prevent steric hinderance and maintain planarity compared to without sulfur atom. The maximum peak of absorption spectra was red-shifted about 50nm with sulfur. The parameters of polymer solar cells in #1 a JSC of 10.3 mAcm-2, VOC of 0.88V, and FF of 0.64, resulting in a PCE of 5.73% with additive effect compared to #2 a JSC of 8.74mA cm-2, VOC of 0.88V, and FF of 0.43, resulting in a PCE of 3.31% without sulfur atom. |
