Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, U.K.
Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, U.K.
ACS Appl Mater Interfaces. 2023 Jul 5;15(26):31684-31691. doi: 10.1021/acsami.3c04282. Epub 2023 Jun 22.
The advent of nonfullerene acceptors (NFAs) enabled records of organic photovoltaics (OPVs) exceeding 19% power conversion efficiency in the laboratory. However, high-efficiency NFAs have so far only been realized in solution-processed blends. Due to its proven track record in upscaled industrial production, vacuum thermal evaporation (VTE) is of prime interest for real-world OPV commercialization. Here, we combine the benchmark solution-processed NFA Y6 with three different evaporated donors in a bilayer (planar heterojunction) architecture. We find that voltage losses decrease by hundreds of millivolts when VTE donors are paired with the NFA instead of the fullerene C, the current standard acceptor in VTE OPVs. By showing that evaporated small-molecule donors behave much like solution-processed donor polymers in terms of voltage loss when combined with NFAs, we highlight the immense potential for evaporable NFAs and the urgent need to direct synthesis efforts toward making smaller, evaporable compounds.
非富勒烯受体（NFAs）的出现使有机光伏（OPV）的实验室功率转换效率超过 19%。然而，高效的 NFAs 迄今为止仅在溶液处理的混合物中实现。由于其在大规模工业生产中的良好记录，真空热蒸发（VTE）是实现实际 OPV 商业化的主要关注点。在这里，我们将基准溶液处理的 NFA Y6 与三种不同的蒸发供体在双层（平面异质结）结构中组合。我们发现，当 VTE 供体与 NFA 而不是富勒烯 C（VTE OPV 中的当前标准受体）配对时，电压损耗会降低数百毫伏。通过证明当与 NFAs 结合时，蒸发小分子供体在电压损耗方面的行为与溶液处理的供体聚合物非常相似，我们突出了可蒸发 NFAs 的巨大潜力，以及迫切需要将合成工作集中在制造更小、可蒸发的化合物上。
