Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510640, P. R. China.
Adv Mater. 2017 Jun;29(21). doi: 10.1002/adma.201606396. Epub 2017 Mar 23.
High-performance nonfullerene polymer solar cells (PSCs) are developed by integrating the nonfullerene electron-accepting material 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2',3'-d']-s-indaceno[1,2-b:5,6-b']dithiophne) (ITIC) with a wide-bandgap electron-donating polymer PTzBI or PTzBI-DT, which consists of an imide functionalized benzotriazole (TzBI) building block. Detailed investigations reveal that the extension of conjugation can affect the optical and electronic properties, molecular aggregation properties, charge separation in the bulk-heterojunction films, and thus the overall photovoltaic performances. Single-junction PSCs based on PTzBI:ITIC and PTzBI-DT:ITIC exhibit remarkable power conversion efficiencies (PCEs) of 10.24% and 9.43%, respectively. To our knowledge, these PCEs are the highest efficiency values obtained based on electron-donating conjugated polymers consisting of imide-functionalized electron-withdrawing building blocks. Of particular interest is that the resulting device based on PTzBI exhibits remarkable PCE of 7% with the thickness of active layer of 300 nm, which is among the highest values of nonfullerene PSCs utilizing thick photoactive layer. Additionally, the device based on PTzBI:ITIC exhibits prominent stability, for which the PCE remains as 9.34% after thermal annealing at 130 °C for 120 min. These findings demonstrate the great promise of using this series of wide-bandgap conjugated polymers as electron-donating materials for high-performance nonfullerene solar cells toward high-throughput roll-to-roll processing technology.
高性能非富勒烯聚合物太阳能电池（PSC）通过整合非富勒烯电子受体材料 3,9-双（2-亚甲基-（3-（1,1-二氰基亚甲基）-茚满酮））-5,5,11,11-四（4-己基苯基）-二噻吩[2,3-d:2',3'-d']-并[1,2-b:5,6-b']二噻吩并[3,2-d]噻吩（ITIC）与宽带隙电子给体聚合物 PTzBI 或 PTzBI-DT 结合而开发，PTzBI-DT 由酰亚胺官能化苯并三唑（TzBI）构建块组成。详细的研究表明，共轭的延伸可以影响光学和电子特性、分子聚集特性、体异质结薄膜中的电荷分离，从而影响整体光伏性能。基于 PTzBI：ITIC 和 PTzBI-DT：ITIC 的单结 PSC 分别表现出显著的功率转换效率（PCE）为 10.24%和 9.43%。据我们所知，这些 PCE 是基于包含酰亚胺官能化吸电子构建块的电子给体共轭聚合物获得的最高效率值。特别值得关注的是，基于 PTzBI 的所得器件表现出显著的 7%的 PCE，活性层厚度为 300nm，这是利用厚光活性层的非富勒烯 PSC 中最高值之一。此外，基于 PTzBI：ITIC 的器件表现出突出的稳定性，在 130°C 下热退火 120 分钟后，其 PCE 仍保持在 9.34%。这些发现表明，使用这一系列宽带隙共轭聚合物作为电子给体材料用于高性能非富勒烯太阳能电池具有很大的潜力，可实现高吞吐量的卷对卷加工技术。
