Xu Xiang, Xiao Jingyang, Zhang Guichuan, Wei Long, Jiao Xuechen, Yip Hin-Lap, Cao Yong
State Key Laboratory of Luminescent Materials and Devices, Institute of Polymer Optoelectronic Materials and Devices, School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China.
State Key Laboratory of Luminescent Materials and Devices, Institute of Polymer Optoelectronic Materials and Devices, School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China; Innovation Center of Printed Photovoltaics, South China Institute of Collaborative Innovation, Dongguan 523808, China.
Sci Bull (Beijing). 2020 Feb 15;65(3):208-216. doi: 10.1016/j.scib.2019.10.019. Epub 2019 Oct 21.
With recent advances in the power conversion efficiency (PCE) of organic solar cells (OSCs) based on novel donor and non-fullerene acceptor (NFAs), improving the stability of these systems has become the most important issue for their practical applications. Herein, an efficient and highly stable OSC, containing a novel polymer donor and a non-fullerene acceptor system, is reported. The OSC is based on an inverted device structure that utilizes a self-assembled fullerene monolayer (C-SAM) as the cathode modification layer, and an efficient and highly stable OSC composes of a polymer donor of poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene-alt-3-fluorothie-no[3,4-b]thiophene-2-carboxylate] (PTB7-Th) and a non-fullerene acceptor of (2,2'-((2Z,2'Z)-(((4,4,9,9-Tetrakis(4-hexylphenyl)-4,9-dihydro-sindaceno[1,2-b:5,6-b']dithiophene-2,7-diyl)bis(4-((2ethylhexyl)oxy)thiophene-5,2-diyl))bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene -2,1-diylidene))dimalononitrile) (IEICO-4F) is presented, showing a PCE of 10%. It further achieves an extrapolated T lifetime (the time required to reach 80% of initial performance) of 34,000 h, operating under one sun illumination equivalent. Based on an estimated solar irradiance of 1500 kWh/(m year) for China, a potential lifetime of 22 years is inferred for the OSC. Further investigation reveals that the reported C-SAM modification stabilizes the OSC active layer morphology by lowering the surface energy of the underlying ZnO electron transport layer and suppressing trap-assisted recombination, thereby improving photostability. The results of this work establish important guidelines for the development of non-fullerene based OSCs with enhanced stability and pave the way for the commercialization of OSC technology.
随着基于新型给体和非富勒烯受体（NFA）的有机太阳能电池（OSC）的功率转换效率（PCE）的最新进展，提高这些系统的稳定性已成为其实际应用中最重要的问题。在此，报道了一种高效且高度稳定的OSC，其包含新型聚合物给体和非富勒烯受体体系。该OSC基于倒置器件结构，利用自组装富勒烯单分子层（C-SAM）作为阴极修饰层，并且展示了一种由聚[4,8-双（5-（2-乙基己基）噻吩-2-基）苯并[1,2-b:4,5-b']二噻吩-alt-3-氟噻吩并[3,4-b]噻吩-2-羧酸酯]（PTB7-Th）的聚合物给体和（2,2'-（（2Z,2'Z）-（（（4,4,9,9-四（4-己基苯基）-4,9-二氢-sindaceno[1,2-b:5,6-b']二噻吩-2,7-二基）双（4-（（2-乙基己基）氧基）噻吩-5,2-二基））双（亚甲基））双（5,6-二氟-3-氧代-2,3-二氢-1H-茚-2,1-二亚基））二丙二腈）（IEICO-4F）的非富勒烯受体组成的高效且高度稳定的OSC，其PCE为10%。在等效的一个太阳光照下运行时，它进一步实现了34,000 h的外推T寿命（达到初始性能的80%所需的时间）。基于中国估计的1500 kWh/（m²·年）的太阳辐照度，推断该OSC的潜在寿命为22年。进一步的研究表明，所报道的C-SAM修饰通过降低底层ZnO电子传输层的表面能并抑制陷阱辅助复合来稳定OSC活性层的形态，从而提高光稳定性。这项工作的结果为开发具有增强稳定性的基于非富勒烯的OSC建立了重要指导原则，并为OSC技术的商业化铺平了道路。
