Cann Jonathan, Farahat Mahmoud E, Welch Gregory C
Department of Chemistry, University of Calgary, 731Campus Place NW, Calgary, Alberta, T2N 1N4, Canada.
ChemSusChem. 2021 Sep 6;14(17):3511-3519. doi: 10.1002/cssc.202002784. Epub 2021 Feb 4.
Organic photovoltaics have found utility as indoor light recycling devices providing an opportunity for the sustainable powering of IoT sensors and related smart electronics. In the report, two organic π-conjugated molecules consisting of four perylene diimide (PDI) chromophores each are presented and used as non-fullerene acceptors in indoor photovoltaic devices. The new materials consist of a dimeric N-annulated PDI core with single PDIs grafted onto the pyrrolic N-atom positions of the core. Compounds PDI e and PDI i are PDI tetramers and differ with PDI e having the terminal N-annulated PDI with pyrrolic N-atom distal to the core and PDI i having the terminal N-annulated PDI with pyrrolic N-atom proximal to the core. The structural and optoelectronic properties were investigated using NMR spectroscopy, optical absorption and emission spectroscopy, and cyclic voltammetry. The compounds exhibit typical optical signatures for PDIs but notable is that the addition of grafted PDI molecules prevents significant aggregation of the dimeric PDI core, as compared to a reference dimer. Use as non-fullerene acceptors in ternary bulk-heterojunction blends with the polymer FBT and fullerene PC BM lead to increased open-circuit voltages and power conversion efficiencies upwards of 13.7 % at 2000 lux light intensity.
有机光伏材料已被用作室内光回收装置，为物联网传感器和相关智能电子产品的可持续供电提供了机会。在该报告中，展示了两种由四个苝二酰亚胺（PDI）发色团组成的有机π共轭分子，并将其用作室内光伏器件中的非富勒烯受体。这些新材料由一个二聚体N-稠合PDI核组成，单个PDI接枝到核的吡咯N原子位置上。化合物PDI e和PDI i是PDI四聚体，不同之处在于PDI e的末端N-稠合PDI的吡咯N原子远离核，而PDI i的末端N-稠合PDI的吡咯N原子靠近核。使用核磁共振光谱、光吸收和发射光谱以及循环伏安法对其结构和光电性能进行了研究。这些化合物表现出典型的PDI光学特征，但值得注意的是，与参考二聚体相比，接枝的PDI分子的加入可防止二聚体PDI核发生显著聚集。在与聚合物FBT和富勒烯PC BM的三元体异质结共混物中用作非富勒烯受体时，在2000勒克斯的光强下可使开路电压和功率转换效率提高到13.7%以上。
