Perylene diimide (PDI) based high bandgap acceptors, DTBTP, DTF2BTP, and DTF2TZP, are synthesized for use in fullerene-free organic solar cells. The two PDI rings are connected to the end of the n-type core, forming a PDI-n-type core-PDI structure. Several n-type core materials, 4,7-dithieno-2,1,3-benzothiadiazole (DTBT), 5,6-difluoro-4,7-dithieno-2,1,3-benzothiadiazole (DTF2BT), and 4,6-difluoro-2H-benzo[d][1,2,3]triazole (DTF2TZ), are incorporated in the PDI acceptors and the n-type core effect on photovoltaic properties is studies. The introduction of alkyl side chains onto the core structure weakened the intermolecular interaction, whereas fluorination of the core structure improved the backbone planarity and intermolecular ordering. DTF2BTP having a planar core structure without bulky alkyl chains yielded the best power conversion efficiency, 4.41%, when mixed with PTB7-Th donor. The n-type core structure was beneficial in terms of increasing the electron accepting properties and the absorption in the high bandgap region of non-fullerene acceptors.

合成了基于di二酰亚胺（PDI）的高带隙受体DTBTP，DTF2BTP和DTF2TZP，用于不含富勒烯的有机太阳能电池。两个PDI环连接到n型核的末端，形成PDI-n型核-PDI结构。几种n型核心材料：4,7-二噻吩并2,1,3-苯并噻二唑（DTBT），5,6-二氟-4,7-二噻吩并2,1,3-苯并噻二唑（DTF2BT）和4，将6-二氟-2H-苯并[d] [1,2,3]三唑（DTF2TZ）掺入PDI受体中，并研究了n型核心对光电性能的影响。烷基侧链引入到核心结构上削弱了分子间的相互作用，而核心结构的氟化改善了主链的平面性和分子间的有序性。DTF2BTP具有平面核结构，没有庞大的烷基链，产生了最佳的功率转换效率，与PTB7-Th供体混合时为4.41％。就增加非富勒烯受体的电子接受性能和在高带隙区的吸收而言，n型核结构是有益的。