Long-lived and disorder-free charge transfer states enable endothermic charge separation in efficient non-fullerene organic solar cells.


Journal

Nature communications
ISSN: 2041-1723
Titre abrégé: Nat Commun
Pays: England
ID NLM: 101528555

Informations de publication

Date de publication:
05 Nov 2020
Historique:
received: 16 07 2020
accepted: 28 09 2020
entrez: 6 11 2020
pubmed: 7 11 2020
medline: 7 11 2020
Statut: epublish

Résumé

Organic solar cells based on non-fullerene acceptors can show high charge generation yields despite near-zero donor-acceptor energy offsets to drive charge separation and overcome the mutual Coulomb attraction between electron and hole. Here, we use time-resolved optical spectroscopy to show that free charges in these systems are generated by thermally activated dissociation of interfacial charge-transfer states that occurs over hundreds of picoseconds at room temperature, three orders of magnitude slower than comparable fullerene-based systems. Upon free electron-hole encounters at later times, both charge-transfer states and emissive excitons are regenerated, thus setting up an equilibrium between excitons, charge-transfer states and free charges. Our results suggest that the formation of long-lived and disorder-free charge-transfer states in these systems enables them to operate closely to quasi-thermodynamic conditions with no requirement for energy offsets to drive interfacial charge separation and achieve suppressed non-radiative recombination.

Identifiants

pubmed: 33154367
doi: 10.1038/s41467-020-19332-5
pii: 10.1038/s41467-020-19332-5
pmc: PMC7645751
doi:

Types de publication

Journal Article

Langues

eng

Sous-ensembles de citation

IM

Pagination

5617

Références

Nat Commun. 2015 Dec 02;6:10085
pubmed: 26626042
J Am Chem Soc. 2015 Feb 18;137(6):2231-4
pubmed: 25658936
Nat Commun. 2019 Jan 23;10(1):398
pubmed: 30674887
Adv Mater. 2020 May;32(19):e1908205
pubmed: 32227399
Nat Commun. 2018 Dec 13;9(1):5295
pubmed: 30546009
Adv Mater. 2011 Apr 12;23(14):1670-4
pubmed: 21387419
Nat Commun. 2019 Jun 5;10(1):2466
pubmed: 31165738
J Am Chem Soc. 2018 Jun 13;140(23):7159-7167
pubmed: 29737160
J Am Chem Soc. 2012 Nov 7;134(44):18189-92
pubmed: 23094985
Science. 2014 Jan 31;343(6170):512-6
pubmed: 24336568
Nat Commun. 2018 Jan 18;9(1):277
pubmed: 29348491
Nature. 2013 Aug 22;500(7463):435-9
pubmed: 23925118
J Am Chem Soc. 2020 Jul 22;142(29):12751-12759
pubmed: 32602706
Chem Rev. 2018 Apr 11;118(7):3447-3507
pubmed: 29557657
Nat Mater. 2017 May;16(5):551-557
pubmed: 28218921
Adv Mater. 2018 Nov;30(45):e1804215
pubmed: 30276887
Nat Commun. 2014 Jul 01;5:4288
pubmed: 24980429
Nat Mater. 2019 May;18(5):459-464
pubmed: 30936478
J Am Chem Soc. 2019 Apr 17;141(15):6362-6374
pubmed: 30882218
J Am Chem Soc. 2019 May 15;141(19):7743-7750
pubmed: 31017418
J Am Chem Soc. 2009 Aug 26;131(33):11819-24
pubmed: 19722595
Nat Commun. 2020 Feb 11;11(1):833
pubmed: 32047157
Adv Mater. 2016 Feb 17;28(7):1482-8
pubmed: 26663421
Nat Mater. 2014 Jan;13(1):63-8
pubmed: 24240240
J Am Chem Soc. 2017 May 10;139(18):6298-6301
pubmed: 28447788
Nano Lett. 2015 Feb 11;15(2):931-5
pubmed: 25585168
J Am Chem Soc. 2014 Mar 5;136(9):3424-9
pubmed: 24521399
Nat Mater. 2018 Aug;17(8):703-709
pubmed: 30013057
Nat Commun. 2018 May 25;9(1):2059
pubmed: 29802311
Nat Commun. 2020 Mar 20;11(1):1488
pubmed: 32198376
Phys Rev Lett. 2015 Mar 27;114(12):128701
pubmed: 25860774
J Am Chem Soc. 2017 Nov 15;139(45):16092-16095
pubmed: 29112393
Nat Commun. 2016 Sep 02;7:12556
pubmed: 27586309
Adv Mater. 2020 Mar;32(9):e1906763
pubmed: 31975446
Nat Commun. 2020 Aug 7;11(1):3943
pubmed: 32770068

Auteurs

Ture F Hinrichsen (TF)

Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK.

Christopher C S Chan (CCS)

Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay,, Hong Kong, China.

Chao Ma (C)

Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay,, Hong Kong, China.

David Paleček (D)

Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK.

Alexander Gillett (A)

Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK.

Shangshang Chen (S)

Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay,, Hong Kong, China.

Xinhui Zou (X)

Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay,, Hong Kong, China.

Guichuan Zhang (G)

Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510640, China.

Hin-Lap Yip (HL)

Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou, 510640, China.

Kam Sing Wong (KS)

Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay,, Hong Kong, China.

Richard H Friend (RH)

Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK. rhf10@cam.ac.uk.

He Yan (H)

Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay,, Hong Kong, China. hyan@ust.hk.

Akshay Rao (A)

Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK. ar525@cam.ac.uk.

Philip C Y Chow (PCY)

Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay,, Hong Kong, China. pcyc@hku.hk.
Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong, China. pcyc@hku.hk.

Classifications MeSH