In this paper, we have fabricated ternary PSC with BTP-eC9 as the host acceptor, IT-M as the guest acceptor, and PM6 as donor. The optimized ternary PSC (PM6:BTP-eC9:IT-M ratio is 1:1.2:0.2) has the highest power conversion efficiency (PCE) of 17.06 % compared to the PM6:BTP-eC9 binary PSC (16.46 %) and PM6:L8-BO reference binary PSC (16.92 %). We systematically investigated the effect of blend acceptors on morphology, photovoltaic performance and charge carrier dynamics. After the addition of IT-M to PM6:BTP-eC9 binary film, the highest (from 26.39 to 26.82 mA cm) was achieved for optimized ternary PSCs compared to PM6:BTP-eC9 binary PSC, which was attributed to the high efficiency of light absorption in the medium to long-wavelength region of IT-M. Shallower lowest unoccupied molecular orbitals (LUMO) level of IT-M enlarged the optical bandgap, which leads to an increase in the open-circuit voltage (, from 0.86 V to 0.875 V). In addition, a small amount of IT-M improves the surface and bulk morphology and crystallinity of the ternary film. The ternary films shown high charge mobility ability. This work demonstrates that supplementing the light absorption and broadening the optical bandgap of PM6:BTP-eC9 binary films by IT-M as third component can effectively improve the PCE and obtain higher photovoltaic performance than that of PM6:BTP-eC9 binary PSCs and PM6:L8-BO reference binary PSCs.

中文翻译：

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使用具有级联能级和互补吸收的两个非富勒烯受体的三元聚合物太阳能电池


在本文中，我们制备了三元PSC，其中BTP-eC9作为主受体，IT-M作为客体受体，PM6作为供体。与 PM6:BTP-eC9 二元 PSC (16.46%) 和 PM6 相比，优化的三元 PSC（PM6:BTP-eC9:IT-M 比例为 1:1.2:0.2）具有最高的功率转换效率 (PCE) 17.06% :L8-BO 参考二进制 PSC (16.92%)。我们系统地研究了共混受体对形态、光伏性能和载流子动力学的影响。在 PM6:BTP-eC9 二元薄膜中添加 IT-M 后，与 PM6:BTP-eC9 二元 PSC 相比，优化的三元 PSC 达到了最高值（从 26.39 到 26.82 mA cm），这归因于 PM6:BTP-eC9 二元 PSC 的高效率IT-M 中长波长区域的光吸收。 IT-M 的最低未占分子轨道 (LUMO) 能级较浅，扩大了光学带隙，从而导致开路电压增加（从 0.86 V 到 0.875 V）。此外，少量的IT-M改善了三元薄膜的表面和体形貌以及结晶度。三元薄膜表现出高电荷迁移能力。这项工作表明，以IT-M作为第三组分补充PM6：BTP-eC9二元薄膜的光吸收并拓宽光学带隙，可以有效提高PCE并获得比PM6：BTP-eC9二元PSC和PM6更高的光伏性能:L8-BO 参考二进制 PSC。