非富勒烯类有机小分子受体材料

Non-Fullerene Organic Small Molecule Acceptor Materials

富勒烯及其衍生物因具有多维电荷传输特性和与给体材料形成独特的相分离结构等特点,在有机光伏领域占据主导地位。然而,富勒烯类受体材料本身也有一些难以克服的缺点,如可见光范围内吸收能力弱、修饰困难、成本高等,进而限制了器件性能的提高和规模化使用。非富勒烯类小分子受体材料的研究引起越来越多的重视。研究者可借助丰富的化学手段,设计合成出具有特定聚集态形貌和优异性能的有机小分子及其寡聚物。本文总结了近几年关于苝四甲酰二亚胺类、吡咯并吡咯二酮类、苯并噻二唑类等几类性能相对优异的非富勒烯类有机小分子受体材料的最新研究进展,从分子结构上对其性能进行了剖析,对高性能受体材料的设计合成具有一定的指导意义。最后,讨论了提高非富勒烯类有机小分子受体材料器件性能的主要因素及其研究前景。

Endowed with high charge transporting capabilities and formation of unique phase-separated microstructure,fullerenes and their derivatives have been playing a predominant role as electron acceptor in bulk hetero-junction devices. However,they also suffer from unconquerable drawbacks,such as poor absorption in visible light region,difficult modification and high cost,which limit the performance improvement and scalable application of organic solar cells. More interests are focused on the non-fullerene small-molecule acceptors. It is reasonable to regulate the molecular energy levels of non-fullerene materials through diversiform chemical approaches,especially for small organic molecules and their oligomers. And electron acceptors with specific aggregated-state morphologies and excellent properties could be accessible by virtue of diverse synthetic methods.In the review,the recent advances on non-fullerene acceptors are summarized with outstanding performance for solution-processed bulk-heterojunction solar cells. These non-fullerene acceptors mainly consist of perylenetetracarboxylic diimide acceptors including its monomers,dimers and quasi-3D-structured acceptors,diketopyrrolopyrrole acceptors, benzothiadiazole-based acceptors, as well as other miscellaneous high-performance small-molecule acceptors. The performance of these acceptors is analyzed from the view of molecular structures and their matching with the related donors. Finally, critical challenges that influence photovoltaic performance and the perspectives of small-molecule acceptors are discussed and addressed.