Investigation of Optical and Dielectric Constants of Benzobis(thiazole)- based Copolymer Films

Author(s): Yue Su, Ailing Yang*, Wenzhe Zhang, Shuguang Wen*

Journal Name: Nanoscience & Nanotechnology-Asia

Volume 10 , Issue 3 , 2020

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Graphical Abstract:


Introduction: Copolymer PBB-T with benzo[1,2-d:4,5-d']bis(thiazole) (BBT) as the accepting unit and benzodithiophene (BDT) as the donor unit is a promising candidate for highperformance non-fullerene polymer solar cells (PSCs). So far optical and dielectric constants of the PBB-T are not fully known.

Method: PBB-T was synthesized and thin films of PBB-T were prepared. By using the Kramers-Kronig relations and the transmission spectra of the PBB-T films, the optical and dielectric constants, including in absorption coefficient (α(λ)), extinction coefficient (κ(λ)), refractive index (n(λ)), dielectric constant (ε1(λ),ε2(λ)), band gap (Eg) and mobility of the PBB-T films were calculated and analyzed.

Result: At 500 nm, α, κ, n, ε1 and ε2 are 1.65×105 cm-1, 0.46, 1.8163, 3.0 and 1.65 respectively. Eg is 2.111 eV. The hole mobility of PBB-T are 2.41×10-5 cm2 V-1 s-1 and 1.71×10-4 cm2 V-1 s-1 for the as-cast film and for the solvent vapor annealed film respectively. The results show that these optical and dielectric constants of the PBB-T films are almost independent on the thicknesses of the films, indicating our results are reliable. The features of the optical and dielectric constants show the PBB-T films are very promising candidates for high-performance non-fullerene PSCs and potential cut-off filter only permitting red and near-infrared light passing.

Conclusion: These results are significant for designing optoelectronic devices related to the PBBT thin films.

Keywords: Benzobis(thiazole)-based copolymer films, Kramers-Kronig relations, transmittance spectra, absorption coefficient, extinction coefficient, refractive index, dielectric constant, band gap, hole mobility.

Lu, L.; Zheng, T.; Wu, Q.; Schneider, A.M.; Zhao, D.; Yu, L. Recent advances in bulk heterojunction polymer solar cells. Chem. Rev., 2015, 115(23), 12666-12731.
Singh, S.P.; Kumar, C.P.; Nagarjuna, P.; Sharma, G.D.; Biswas, S.; Mikroyannidis, J.A. Diarylmethanofullerene: Efficient polymer solar cells with low-band-gap copolymer. J. Phys. Chem. C, 2013, 117(26), 13350-13356.
Guo, S.; Wang, W.; Herzig, E.M.; Naumann, A.; Tainter, G.; Perlich, J.; Müller-Buschbaum, P. Solvent-morphology-property relationship of PTB7: PC71BM polymer solar cells. ACS Appl. Mater. Interfaces, 2017, 9(4), 3740-3748.
Fraga, D.I.; Distler, A.; Lüer, L. Stability of organic solar cells: The influence of nanostructured carbon materials. Adv. Energy Mater., 2017, 7(10) 1601320
Kan, B.; Zhang, J.; Liu, F.; Wan, X.; Li, C.; Ke, X.; Wang, Y.; Feng, H.; Zhang, Y.; Long, G.; Friend, R.H.; Bakulin, A.A.; Chen, Y. Fine-tuning the energy levels of a nonfullerene small-molecule acceptor to achieve a high short-circuit current and a power conversion efficiency over 12% in organic solar cells. Adv. Mater., 2018, 30(3) 1704904
Yao, Z.; Liao, X.; Gao, K.; Lin, F.; Xu, X.; Shi, X.; Zuo, L.; Liu, F.; Chen, Y.; Jen, A.K.Y. Dithienopicenocarbazole-based acceptors for efficient organic solar cells with optoelectronic response over 1000 nm and an extremely low energy loss. J. Am. Chem. Soc., 2018, 140(6), 2054-2057.
Xu, S.J.; Zhou, Z.; Liu, W.; Zhang, Z.; Liu, F.; Yan, H.; Zhu, X. A twisted thieno[3,4-b]thiophene-based electron acceptor featuring a 14-π-electron indenoindene core for high-performance organic photovoltaics. Adv. Mater., 2017, 29(43) 1704510
Yao, H.; Cui, Y.; Yu, R.; Gao, B.; Zhang, H.; Hou, J. Design, synthesis, and photovoltaic characterization of a small molecular acceptor with an ultra-narrow band gap. Angew. Chem. Int. Ed., 2017, 56(11), 3045-3049.
Holliday, S.; Ashraf, R.S.; Nielsen, C.B.; Kirkus, M.; Röhr, J.A.; Tan, C.; Collado-Fregoso, E.; Knall, A.; Durrant, J.R.; Nelson, J.; McCulloch, I. A rhodanine flanked nonfullerene acceptor for solution-processed organic photovoltaics. J. Am. Chem. Soc., 2015, 137(2), 898-904.
Liu, R.; Du, Z.; Wen, S.; Wu, Y.; Zhu, D.; Yang, R. Energy levels modulation of small molecule acceptors for polymer solar cells. Synth. Met., 2018, 235, 131-135.
Bin, H.; Zhang, Z.; Gao, L.; Chen, S.; Zhong, L.; Xue, L.; Yang, C.; Li, Y. Non-fullerene polymer solar cells based on alkylthio and fluorine substituted 2D-conjugated polymers reach 9.5% efficiency. J. Am. Chem. Soc., 2016, 138(13), 4657-4664.
Xu, X.; Yu, T.; Bi, Z.; Ma, W.; Li, Y.; Peng, Q. Realizing over 13% efficiency in green-solvent-processed nonfullerene organic solar cells enabled by 1,3,4-thiadiazole-based wide-bandgap copolymers. Adv. Mater., 2018, 30(3) 1703973
Lin, Y.; Zhao, F.; Wu, Y.; Chen, K.; Xia, Y.; Li, G.; Prasad, S.K.K.; Zhu, J.; Huo, L.; Bin, H.; Zhang, Z.; Guo, X.; Zhang, M.; Sun, Y.; Gao, F.; Wei, Z.; Ma, W.; Wang, C.; Hodgkiss, J.; Bo, Z.; Inganäs, O.; Li, Y.; Zhan, X. Mapping polymer donors toward high-efficiency fullerene free organic solar cells. Adv. Mater., 2017, 29(3) 1604155
Yao, H.; Yu, R.; Shin, T.J.; Zhang, H.; Zhang, S.; Jang, B.; Uddin, M.A.; Woo, H.Y.; Hou, J. A wide bandgap polymer with strong π-π interaction for efficient fullerene-free polymer solar cells. Adv. Energy Mater., 2016, 6(15) 1600742
Chen, S.; Liu, Y.; Zhang, L.; Chow, P.C.Y.; Wang, Z.; Zhang, G.; Ma, W.; Yan, H. A wide-bandgap donor polymer for highly efficient non-fullerene organic solar cells with a small voltage loss. J. Am. Chem. Soc., 2017, 139(18), 6298-6301.
Mo, D.; Wang, H.; Chen, H.; Qu, S.; Chao, P.; Yang, Z.; Tian, L.; Su, Y.; Gao, Y.; Yang, B.; Chen, W.; He, F. Chlorination of low-band-gap polymers: toward high-performance polymer solar cells. Chem. Mater., 2017, 29(7), 2819-2830.
Zhao, W.; Zhang, S.; Zhang, Y.; Li, S.; Liu, X.; He, C.; Zheng, Z.; Hou, J. Environmentally friendly solvent-processed organic solar cells that are highly efficient and adaptable for the blade-coating method. Adv. Mater., 2018, 30(4) 1704837
Bin, H.; Gao, L.; Zhang, Z.; Yang, Y.; Zhang, Y.; Zhang, C.; Chen, S.; Xue, L.; Yang, C.; Xiao, M.; Li, Y. 11.4% efficiency non-fullerene polymer solar cells with trialkylsilyl substituted 2D-conjugated polymer as donor. Nat. Commun., 2016, 7(1), 13651.
Tam, T.L.D.; Lin, T.T. Tuning energy levels and film morphology in benzodithiophene-thienopyrrolodione copolymers via nitrogen substitutions. Macromolecules, 2016, 49(5), 1648-1654.
Dessì, A.; Barozzino, C.G.; Calamante, M.; Reginato, G.; Mordini, A.; Peruzzini, M.; Taddei, M.; Sinicropi, A.; Parisi, M.L.; Fabrizi De Biani, F.; Basosi, R.; Mori, R.; Spatola, M.; Bruzzi, M.; Zani, L. Organic chromophores based on a fused bis-thiazole core and their application in dye-sensitized solar cells. Eur. J. Org. Chem., 2013, 10, 1916-1928.
Jeong, E.; Kim, G.H.; Jung, I.H.; Jeong, P.; Kim, J.Y. 2,5-di(thiophen-2-yl)thiazolo[5,4-d]thiazole-based donor–acceptor type copolymers for photovoltaic cells. Curr. Appl. Phys., 2012, 12(1), 11-16.
Wu, P.; Xin, H.; Kim, F.S.; Ren, G.; Jenekhe, S.A. Regioregular poly(3-pentylthiophene): Synthesis, self-assembly of nanowires, high-mobility field-effect transistors, and efficient photovoltaic cells. Macromolecules, 2009, 42(22), 8817-8826.
Bhuwalka, A.; Ewan, M.D.; Elshobaki, M.; Mike, J.F.; Tlach, B.; Chaudhary, S. Synthesis and photovoltaic properties of 2,6-Bis(2-Thienyl) benzobisazole and 4,8-bis(thienyl)-benzo[1,2-B:4,5-B]dithiophene copolymers. Polym. Sci., Part. Polym. Chem., 2016, 54(3), 316-324.
Mamada, M.; Nishida, J.; Tokito, S.; Yamashita, Y. Preparation, characterization, and field-effect transistor performance of benzo[1,2-d:4,5-d0]bisthiazole derivatives. Chem. Lett., 2008, 37(7), 766-767.
Ahmed, E.; Subramaniyan, S.; Kim, F.S.; Xin, H.; Jenekhe, S.A. Benzobisthiazole-based donor-acceptor copolymer semiconductors for photovoltaic cells and highly stable field-effect transistors. Macromolecules, 2011, 44(18), 7207-7219.
Lucarini, V.; Saarinen, J.J.; Peiponen, K.E.; Vartiainen, E.M. Kramers-Kronig Relations in optical materials research; Springer: Germany, 2005.
Kittel, C. Introduction to solid state physics, 8th ed; John Wiley & Sons: New Jersy, USA, 2005.
Xue, S.W.; Zu, X.T.; Zheng, W.G.; Deng, H.X.; Xiang, X. Effects of Al doping concentration on optical parameters of ZnO:Al thin films by sol-gel technique. Phys. B, 2006, 381(1-2), 209-213.
Xue, S.W.; Zu, X.T.; Zhou, W.L.; Deng, H.X.; Xiang, X.; Zhang, L.; Deng, H. Effects of post-thermal annealing on the optical constants of ZnO thin film. Alloys Compd., 2008, 448(1-2), 21-26.
Yang, A.L.; Bao, X.C.; Li, S.P.; Yang, R.Q.; Wang, T.; Wang, Y.J. Nano-zno film preparation at low temperature and the optical indices calculation. Opelectro. Lett., 2014, 10(3), 216-220.
El-Menyawy, E.M.; Zedan, I.T. Optical properties and device characteristics of 2-(antipyrin-4-ylhydrazono)-2-(4-nitrophenyl)acetonitrile thin films for photodiode applications. Spectrochim. Acta Part A., 2015, 137, 810-816.
Yang, A.L.; Wang, Z.; Zhang, W.Z.; Su, Y.; Bao, X.C.; Zhu, D.Q. In: Retrieval of optical and dielectric constants of PBDTTTPD polymer film by unconstrained optimization method; In: 2018 International conference on computational modeling, simulation and mathematical statistics, Xi’an, China, June 24-25, 2018; DEStech Transactions on Computer Science and Engineering, 2018, DEStech, USA. , 2018; pp. 223-230.
Camaioni, N.; Po, R. Pushing the envelope of the intrinsic limitation of organic solar cells. Phys. Chem. Lett., 2013, 4(11), 1821-1828.
Wen, S.G.; Li, Y.; Rath, T.; Li, Y.H.; Bao, X.C.; Han, L.L.; Ehmann, H.; Trimmel, G.; Zhang, Y.; Yang, R.Q. Exploring a benzobis(thiazole)-based copolymer in highly efficient non-fullerene polymer solar cells. Chem. Mater., 2019, 31, 919-926.

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Year: 2020
Page: [350 - 355]
Pages: 6
DOI: 10.2174/2210681209666190306145042
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