title: A polymer tandem solar cell with 10.6% power conversion efficiency.
abstract: An effective way to improve polymer solar cell efficiency is to use a tandem structure, as a broader part of the spectrum of solar radiation is used and the thermalization loss of photon energy is minimized. In the past, the lack of high-performance low-bandgap polymers was the major limiting factor for achieving high-performance tandem solar cell. Here we report the development of a high-performance low bandgap polymer (bandgap <1.4 eV), poly[2,7-(5,5-bis-(3,7-dimethyloctyl)-5H-dithieno[3,2-b:2',3'-d]pyran)-alt-4,7-(5,6-difluoro-2,1,3-benzothia diazole)] with a bandgap of 1.38 eV, high mobility, deep highest occupied molecular orbital. As a result, a single-junction device shows high external quantum efficiency of >60% and spectral response that extends to 900 nm, with a power conversion efficiency of 7.9%. The polymer enables a solution processed tandem solar cell with certified 10.6% power conversion efficiency under standard reporting conditions (25 °C, 1,000 Wm(-2), IEC 60904-3 global), which is the first certified polymer solar cell efficiency over 10%.
authors: Department of Material Science and Engineering, University of California, Los Angeles, Los Angeles, California 90095, USA.
authors: Jingbi
authors: J
authors: You
authors: Letian
authors: L
authors: Dou
authors: Ken
authors: K
authors: Yoshimura
authors: Takehito
authors: T
authors: Kato
authors: Kenichiro
authors: K
authors: Ohya
authors: Tom
authors: T
authors: Moriarty
authors: Keith
authors: K
authors: Emery
authors: Chun-Chao
authors: CC
authors: Chen
authors: Jing
authors: J
authors: Gao
authors: Gang
authors: G
authors: Li
authors: Yang
authors: Y
authors: Yang
references: Adv Mater. 2011 Oct 25;23(40):4636-43
references: 21905131
references: J Am Chem Soc. 2008 Dec 3;130(48):16144-5
references: 18989961
references: J Am Chem Soc. 2012 Jun 20;134(24):10071-9
references: 22640170
references: Science. 2007 Jul 13;317(5835):222-5
references: 17626879
references: Adv Mater. 2012 Oct 2;24(38):5267-72
references: 22833348
references: Angew Chem Int Ed Engl. 2003 Jul 28;42(29):3371-5
references: 12888961
references: Chem Rev. 2007 Apr;107(4):1324-38
references: 17428026
references: J Am Chem Soc. 2009 Jun 10;131(22):7792-9
references: 19453105
references: J Am Chem Soc. 2011 Mar 30;133(12):4625-31
references: 21375339
references: Nano Lett. 2005 Dec;5(12):2408-13
references: 16351187
references: Phys Rev Lett. 2012 Jan 13;108(2):026601
references: 22324702
references: Nano Lett. 2011 Aug 10;11(8):3099-107
references: 21770452
references: Nat Chem. 2009 Nov;1(8):657-61
references: 21378958
references: J Am Chem Soc. 2009 Nov 25;131(46):16616-7
references: 19886605
references: Adv Mater. 2011 Mar 11;23(10):1282-6
references: 20830710
references: Adv Mater. 2010 Jan 19;22(3):380-3
references: 20217723
references: Angew Chem Int Ed Engl. 2008;47(1):58-77
references: 18041798
references: Adv Mater. 2010 May 25;22(20):E135-8
references: 20641094
references: Phys Rev Lett. 2000 May 22;84(21):4946-9
references: 10990838
references: J Am Chem Soc. 2010 Feb 3;132(4):1377-82
references: 20055460
references: Adv Mater. 2010 Feb 23;22(8):E67-71
references: 20217802
references: Adv Mater. 2011 Apr 12;23(14):1679-83
references: 21472797
references: Adv Mater. 2011 Aug 9;23(30):3465-70
references: 21688327
references: Angew Chem Int Ed Engl. 2011 Mar 21;50(13):2995-8
references: 21370359