Low band-gap polymers based on quinoxaline derivatives and fused thiophene as donor materials for high efficiency bulk-heterojunction photovoltaic cells
作者:Jang-Yong Lee、Won-Suk Shin、Jung-Rim Haw、Doo-Kyung Moon
DOI:10.1039/b823536h
日期:——
In this study we synthesized three low band-gap polymers—poly[2,3-bis(4-hexyloxyphenyl)quinoxaline-alt-2,5-thieno[3,2-b]thiophene] (PQTT), poly[2,3-bis(4-hexyloxyphenyl)quinoxaline-alt-3,6-dipentadecylthieno[3,2-b]thiophene] (PQPDTT) and poly[2,3-bis(4-hexyloxyphenyl)quinoxaline-alt-2,5-bis(thieno-2-yl)-3,6-dipentadecylthieno[3,2-b]thiophene] (PQTPDTT)—that are based on quinoxaline and thieno[3,2-b]thiophene, and examined their photovoltaic properties. The band-gaps of PQTT and PQTPDTT were 1.65eV and 1.7eV, respectively. For PQTPDTT, a HOMO level of −5.12eV, which was lower than that of P3HT, was observed. According to the analysis of the characteristics of the photovoltaic device using PC61BM and PC71BM as acceptors, an open circuit voltage (VOC) of 0.71V, a short circuit current (JSC) of 8.80mA/cm2, a fill factor of 0.36 and a power conversion efficiency (PCE) of 2.27% were observed at 100mW/cm2 (AM 1.5 illumination) when a PQTPDTT/PC71BM blend film was used as the active layer. A very high incident photon to current efficiency (IPCE) was detected (60% at 400nm, 57% at 500nm).
和聚[2,3-双(4-己氧基苯基)喹喔啉-alt-2,5-双(噻吩-2-基)-3,6-二十五烷基噻吩并[3,2-b]噻吩](PQTPDTT),并研究了它们的光伏特性。PQTT 和 PQTPDTT 的带隙分别为 1.65eV 和 1.7eV。PQTPDTT 的 HOMO 电平为 -5.12eV,低于 P3HT 的 HOMO 电平。根据对使用 PC61BM 和 PC71BM 作为受体的光伏器件的特性分析,当使用 PQTPDTT/PC71BM 混合薄膜作为活性层时,在 100mW/cm2 (AM 1.5 照明)条件下,开路电压 (VOC) 为 0.71V,短路电流 (JSC) 为 8.80mA/cm2,填充因子为 0.36,功率转换效率 (PCE) 为 2.27%。检测到的入射光子电流效率(IPCE)非常高(400 纳米波长为 60%,500 纳米波长为 57%)。