Abstract
The open-circuit voltage (V oc) is one of the important parameters that influence the power conversion efficiency (PCE) of polymer solar cells. Its value is mainly determined by the energy level offset between the highest occupied molecular orbital (HOMO) of the donor and the lowest unoccupied molecular orbital (LUMO) of the acceptor. Therefore, decreasing the HOMO value of the polymer could lead to a high V oc and thus increasing the cell efficiency. Here we report a facile way to lower the polymer HOMO energy level by using methoxyl substituted-benzodithiophene (BDT) unit. The polymer with the methoxyl functionl group (POBDT(S)-T1) exhibited a HOMO value of–5.65 eV, which is deeper than that (–5.52 eV) of polymer without methoxyl unit (PBDT(S)-T1). As a result, POBDT(S)-T1-based solar cells show a high V oc of 0.98 V and PCE of 9.2%. In contrast, PBDT(S)-T1-based devices show a relatively lower V oc of 0.89 V and a moderate PCE of 7.4%. The results suggest that the involvement of methoxyl group into conjugated copolymers can efficiencly lower their HOMO energy levels.
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References
Zhao J, Li Y, Yang G, Jiang K, Lin H, Ade H, Ma W, Yan H. Nat Energ, 2016, 1: 15027–15029
You J, Dou L, Yoshimura K, Kato T, Ohya K, Moriarty T, Emery K, Chen CC, Gao J, Li G, Yang Y. Nat Commun, 2013, 4: 1446–1455
Liu Y, Zhao J, Li Z, Mu C, Ma W, Hu H, Jiang K, Lin H, Ade H, Yan H. Nat Commun, 2014, 5: 5293–5300
Liao SH, Jhuo HJ, Yeh PN, Cheng YS, Li YL, Lee YH, Sharma S, Chen SA. Sci Rep, 2014, 4: 6813–6819
He Z, Xiao B, Liu F, Wu H, Yang Y, Xiao S, Wang C, Russell TP, Cao Y. Nat Photon, 2015, 9: 174–179
Yusoff ARM, Kim D, Kim HP, Shneider FK, da Silva WJ, Jang J. Energ Environ Sci, 2015, 8: 303–316
You J, Chen CC, Hong Z, Yoshimura K, Ohya K, Xu R, Ye S, Gao J, Li G, Yang Y. Adv Mater, 2013, 25: 3973–3978
Zheng Z, Zhang S, Zhang M, Zhao K, Ye L, Chen Y, Yang B, Hou J. Adv Mater, 2015, 27: 1189–1194
Huo L, Liu T, Fan B, Zhao Z, Sun X, Wei D, Yu M, Liu Y, Sun Y. Adv Mater, 2015, 27: 6969–6975
Huo L, Liu T, Sun X, Cai Y, Heeger AJ, Sun Y. Adv Mater, 2015, 27: 2938–2944
Park SH, Shin I, Kim KH, Street R, Roy A, Heeger AJ. Adv Mater, 2015, 27: 298–302
Chen JD, Cui C, Li YQ, Zhou L, Ou QD, Li C, Li Y, Tang JX. Adv Mater, 2015, 27: 1035–1041
Lu L, Zheng T, Wu Q, Schneider AM, Zhao D, Yu L. Chem Rev, 2015, 115: 12666–12731
You J, Dou L, Hong Z, Li G, Yang Y. Prog Polymer Sci, 2013, 38: 1909–1928
Li Y. Acc Chem Res, 2012, 45: 723–733
Price SC, Stuart AC, Yang L, Zhou H, You W. J Am Chem Soc, 2011, 133: 4625–4631
Zhou H, Yang L, You W. Macromolecules, 2012, 45: 607–632
Liang Y, Feng D, Wu Y, Tsai ST, Li G, Ray C, Yu L. J Am Chem Soc, 2009, 131: 7792–7799
Huo L, Chen TL, Zhou Y, Hou J, Chen HY, Yang Y, Li Y. Macromolecules, 2009, 42: 4377–4380
Huo L, Li Z, Guo X, Wu Y, Zhang M, Ye L, Zhang S, Hou J. Polym Chem, 2013, 4: 3047–3056
Cheng X, Wan Q, Wu Y, Guo B, Guo X, Li Y, Zhang M, Cui C, Li Y. Sol Energ Mat Sol C, 2016, 149: 162–169
Huo L, Zhou Y, Li Y. Macromol Rapid Commun, 2009, 30: 925–931
Cui C, Wong WY, Li Y. Energ Environ Sci, 2014, 7: 2276–2284
Ye L, Zhang S, Zhao W, Yao H, Hou J. Chem Mater, 2014, 26: 3603–3605
Huo L, Zhang S, Guo X, Xu F, Li Y, Hou J. Angew Chem Int Ed, 2011, 50: 9697–9702
Xue X, Fan B, Liu T, Sun X, Huo L, Ha SR, Choi H, Kim T, Kim JY, Wei D, Yu M, Jin Q, Sun Y. Polym Chem, 2016, 7: 4036–4045
Cui C, He Z, Wu Y, Cheng X, Wu H, Li Y, Cao Y, Wong WY. Energ Environ Sci, 2016, 9: 885–891
Zhang S, Ye L, Zhao W, Yang B, Wang Q, Hou J. Sci China Chem, 2015, 58: 248–256
Li Y. Sci China Chem, 2016, 59: 1430–1431
Meyer F. Prog Polymer Sci, 2015, 47: 70–91
Ie Y, Huang J, Uetani Y, Karakawa M, Aso Y. Macromolecules, 2012, 45: 4564–4571
Hexemer A, Bras W, Glossinger J, Schaible E, Gann E, Kirian R, Mac Dowell A, Church M, Rude B, Padmore H. J Phys-Conf Ser, 2010, 247: 012007
Gann E, Young AT, Collins BA, Yan H, Nasiatka J, Padmore HA, Ade H, Hexemer A, Wang C. Rev Sci Instrum, 2012, 83: 045110
Ma W, Tumbleston JR, Wang M, Gann E, Huang F, Ade H. Adv Energ Mater, 2013, 3: 864–872
Li Y, Cao Y, Gao J, Wang D, Yu G, Heeger AJ. Synth Met, 1999, 99: 243–248
Di Nuzzo D, Aguirre A, Shahid M, Gevaerts VS, Meskers SCJ, Janssen RAJ. Adv Mater, 2010, 22: 4321–4324
Huang W, Li M, Zhang L, Yang T, Zhang Z, Zeng H, Zhang X, Dang L, Liang Y. Chem Mater, 2016, 28: 5887–5895
Acknowledgments
This work was supported by the National Natural Science Foundation of China (51273203, 51261160496, 51473009, 21504066), the International Science & Technology Cooperation Program of China (2014DFA52820), the Ministry of Science and Technology (2016YFA0200700), and the Fundamental Research Funds for the Central Universities (YWF-14-HXXY-014, YWF-15-HHXY-003). X-ray data was acquired at beamlines 7.3.3 and 11.0.1.2 at Advanced Light Source, which is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract (DE-AC02-05CH11231).
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Xue, X., Liu, T., Meng, X. et al. Enhanced open-circuit voltage in methoxyl substituted benzodithiophene-based polymer solar cells. Sci. China Chem. 60, 243–250 (2017). https://doi.org/10.1007/s11426-016-0349-7
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DOI: https://doi.org/10.1007/s11426-016-0349-7