Marked Consequences of Systematic Oligothiophene Catenation in Thieno[3,4-c]pyrrole-4,6-dione and Bithiopheneimide Photovoltaic Copolymers

Zhou, Nanjia1,2; Guo, Xugang2,3,4; Ponce Ortiz, Rocio5; Harschneck, Tobias2,3; Manley, Eric F.2,3,6; Lou, Sylvia J.2,3; Hartnett, Patrick E.2,3; Yu, Xinge2,3; Horwitz, Noah E.2,3; Mayorga Burrezo, Paula5; Aldrich, Thomas J.2,3; Lopez Navarrete, Juan T.5; Wasielewski, Michael R.2,3; Chen, Lin X.2,3,6; Chang, Robert. P. H.1,2; Facchetti, Antonio2,3,7; Marks, Tobin J.1,2,3

2015-10-07

10.1021/jacs.5b06462

Journal of the American Chemical Society   影响因子和分区

0002-7863

As effective building blocks for high-mobility transistor polymers, oligothiophenes are receiving attention for polymer solar cells (PSCs) because the resulting polymers can effectively suppress charge recombination. Here we investigate two series of in-chain donor acceptor copolymers, PTPDnT and PBTInT, based on thieno[3,4-dpyrrole-4,6-dione (TPD) or bithiopheneimide (BTI) as electron acceptor units, respectively, and oligothiophenes (nTs) as donor counits, for high-performance PSCs. Intramolecular S center dot center dot center dot O interaction leads to more planar TPD polymer backbones, however backbone torsion yields greater open-circuit voltages for BTI polymers. Thiophene addition progressively raises polymer HOMOs but marginally affects their band gaps. FT-Raman spectra indicate that PTPDnT and PBTInT conjugation lengths scale with nT catenation up to n = 3 and then saturate for longer oligomer. Furthermore, the effects of oligothiophene alkylation position are explored, revealing that the alkylation pattern greatly affects film morphology and PSC performance. The 3T with "outward" alkylation in PTPD3T and PBTI3T affords optimal pi-conjugation, close stacking, long-range order, and high hole mobilities (0.1 cm(2)/(V s)). These characteristics contribute to the exceptional similar to 80% fill factors for PTPD3T-based PSCs with PCE = 7.7%. The results demonstrate that 3T is the optimal donor unit among nTs (n = 1-4) for photovoltaic polymers. Grazing incidence wide-angle X-ray scattering, transmission electron microscopy, and time-resolved microwave conductivity measurements reveal that the terthiophene-based PTPD3T blend maintains high crystallinity with appreciable local mobility and long charge carrier lifetime. These results provide fundamental materials structure-device performance correlations and suggest guidelines for designing oligothiophene-based polymers with optimal thiophene catenation and appropriate alkylation pattern to maximize PSC performance.

SCI ; EI

英语

NI期刊

通讯

U.S. DOE[DE-AC02-06CH11357]

Chemistry

Chemistry, Multidisciplinary

WOS:000362628300029

AMER CHEMICAL SOC

20154101375879

Alkylation ; Carrier lifetime ; Carrier mobility ; Crystallinity ; Energy gap ; High resolution transmission electron microscopy ; Open circuit voltage ; Polymer solar cells ; Thiophene ; X ray scattering

Electricity: Basic Concepts and Phenomena:701.1 ; Semiconducting Materials:712.1 ; Optical Devices and Systems:741.3 ; Chemical Reactions:802.2 ; Organic Compounds:804.1 ; Polymeric Materials:815.1 ; High Energy Physics:932.1

Web of Science

1.Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA
2.Northwestern Univ, Mat Res Ctr, Argonne Northwestern Solar Energy Res Ctr, Evanston, IL 60208 USA
3.Northwestern Univ, Dept Chem, Evanston, IL 60208 USA
4.South Univ Sci & Technol China, Dept Mat Sci & Engn, Shenzhen 518055, Guangdong, Peoples R China
5.Univ Malaga, Dept Phys Chem, E-29071 Malaga, Spain
6.Argonne Natl Lab, Chem Sci & Engn Div, Argonne, IL 60439 USA
7.Polyera Corp, Skokie, IL 60077 USA

Zhou, Nanjia,Guo, Xugang,Ponce Ortiz, Rocio,et al. Marked Consequences of Systematic Oligothiophene Catenation in Thieno[3,4-c]pyrrole-4,6-dione and Bithiopheneimide Photovoltaic Copolymers[J]. Journal of the American Chemical Society,2015,137(39):12565-12579.

Zhou, Nanjia.,Guo, Xugang.,Ponce Ortiz, Rocio.,Harschneck, Tobias.,Manley, Eric F..,...&Marks, Tobin J..(2015).Marked Consequences of Systematic Oligothiophene Catenation in Thieno[3,4-c]pyrrole-4,6-dione and Bithiopheneimide Photovoltaic Copolymers.Journal of the American Chemical Society,137(39),12565-12579.

Zhou, Nanjia,et al."Marked Consequences of Systematic Oligothiophene Catenation in Thieno[3,4-c]pyrrole-4,6-dione and Bithiopheneimide Photovoltaic Copolymers".Journal of the American Chemical Society 137.39(2015):12565-12579.