A new nonfullerene acceptor with an extended π conjugation core enables ternary organic solar cells approaching 19%efficiency  

作　　者：Chunyan Liu Nailiang Qiu Zhengjin Li Yan Lu 

机构地区：[1]School of Materials Science and Engineering,Tianjin Key Laboratory for Photoelectric Materials and Devices,Key Laboratory of Display Materials and Photoelectric Devices,Ministry of Education,Tianjin University of Technology,Tianjin 300384,China [2]School of Chemistry,Chemical Engineering and Materials,Jining University,Qufu 273155,China

出　　处：《Nano Research》2024年第5期4062-4068,共7页纳米研究（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.52173010);Jining University(Nos.2022HHKJ11,2019BSZX01).

摘　　要：In organic solar cells(OSCs),it is an effective way to improve the power conversion efficiency(PCE)by adding a guest component with appropriate absorption and energy levels in the host system.Herein,a new nonfullerene acceptor(NFA)named TBF-2Cl was developed by the strategy of expanding theπconjugated core of 2,2’-(((4,4,9,9-tetrahexyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b’]dithiophene-2,7-diyl)bis(methaneylylidene))bis(5,6-dichloro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile(IDT-4Cl)with two benzene rings.With increase of benzene units,TBF-2Cl exhibits higher lowest unoccupied molecular orbital(LUMO)level of-3.75 eV than that of one benzene unit based NFA IDT-4Cl and fluorene core based NFA F-2Cl,which facilitates enhancing the open-circuit voltage(V_(oc))of ternary devices.Moreover,TBF-2Cl film shows a medium optical bandgap with the absorption range from 500-800 nm,being well complementary with the wide bandgap polymer donor D18 and narrow bandgap NFA CH-6F.Accordingly,a remarkable PCE of 18.92%with a high short-circuit current density(J_(sc))of 27.40 mA·cm^(-2),a fill factor(FF)of 0.749,especially an outstanding V_(oc) of 0.922 V was achieved for the optimal ternary device based on D18:TBF-2Cl:CH-6F,surpassing the binary counterpart(17.08%).The findings provide insight into the development of new guest acceptors for obtaining more efficient OSCs.

关 键 词：medium optical bandgap high lowest unoccupied molecular orbital(LUMO)level the third component ternary organic solar cell high open-circuit voltage 

分 类 号：O62[理学—有机化学]