叠层聚合物太阳电池取得接近15%的光伏效率

A Tandem Polymer Solar Cell Based on Non-fullerene-acceptors Yields an Efficiency Approaching 15%

聚合物太阳能电池(polymer solar cell,简称PSC)是重要的光电转换器件.近年来,基于非富勒烯型电子受体的聚合物太阳能电池(NF-PSC)发展迅速.迄今为止,单结NF-PSC的光伏效率已经达到13%以上,超过了传统的富勒烯型聚合物太阳能电池.相比于单结NF-PSC,叠层NF-PSC有助于克服外量子效率受限和热损耗偏高的问题.然而,叠层NF-PSC的构筑,对于材料的设计要求更高,器件制备的难度也更大,因而发展相对缓慢.最近,侯剑辉等对叠层NF-PSC中的前、后子电池之间的光谱匹配性进行了优化调制,选用窄带隙的PTB7-Th:IEICO-4F作为后电池,宽带隙的J52-2F:IT-M作为前电池,来构建叠层NF-PSC,将光伏效率进一步提升到了14.9%,目前为该领域的最高值.本文将简要介绍NF-PSC的发展概况,评述这一突出的研究成果,总结中国学术界在NF-PSC领域做出的卓越贡献,并展望该领域的广阔前景.

In polymer solar cells（PSCs）,the blends of polymer donors and fullerene-based acceptors have been predominantly used for over two decades.This situation has been challenged owing to the rapid progress in non-fullerene（NF） PSCs.Up to now,the power conversion efficiencies（PCEs） of single-junction NF-PSCs have reached over 13% and surpassed that of the fullerene-based counterparts.Tandem double-junction solar cells are intrinsically more potential for enhancing PCE but bring more challenges for material design and device fabrication.Recently,in order to optimize light response spectrum of tandem NF-PSCs and hence to promote PCE,Hou et al.modulated the photoactive layer compositions by adopting a series of polymer donors and NF-acceptors.They found that light response spectrum of the blend of J52-2F：IT-M was well complementary with that of PTB7-Th：IEICO-4F,and as a result,the tandem NF-PSC based on these two blends could offer a broad and strong light response spectra covering 400 – 1000 nm.After optimizing device fabrication process,they realized a PCE of 14.9%,which is the top value in the field.Herein,by making a brief overview of NF-PSCs and highlighting this outstanding result,this short essay not only aims to attract attention to the rapid progress made by Chinese academic community but also delivers the expectation for the bright future of NF-PSCs.