TY - JOUR
T1 - Regulating the Aggregation of Unfused Non-Fullerene Acceptors via Molecular Engineering towards Efficient Polymer Solar Cells
AU - Li, Yuxiang
AU - Fu, Huiting
AU - Wu, Ziang
AU - Wu, Xin
AU - Wang, Mei
AU - Qin, Hongmei
AU - Lin, Francis
AU - Woo, Han Young
AU - Jen, Alex K.Y.
N1 - Funding Information:
A. K.-Y. J. thanks for the sponsorship of the Lee Shau-Kee Chair Professor (Materials Science). This work was supported by the APRC Grants of the City University of Hong Kong (9380086), Innovation and Technology Bureau (ITS/497/18FP, GHP/021/18SZ), Guangdong-Hong Kong-Macao joint laboratory of optoelectronic and magnetic materials (2019B121205002), and Collaborative Research Fund grant (C5037-18G) from the Research Grants Council of Hong Kong, Guangdong Major Project of Basic and Applied Basic Research (2019B030302007), and the Office of Naval Research (N00014-20-1-2191). H.Y.W. thanks the financial support from the National Research Foundation (NRF) of Korea (NRF-2016M1A2A2940911 and 2019R1A6A1A11044070). Y. L. is grateful for the support from the Hong Kong Scholars Program (XJ2019-026), the Science and Technology Program of Shaanxi Province (2019JQ-244), the Outstanding Youth Science and Technology Foundation of Xi'an University of Science and Technology (2019YQ3-03).
Funding Information:
A. K.‐Y. J. thanks for the sponsorship of the Lee Shau‐Kee Chair Professor (Materials Science). This work was supported by the APRC Grants of the City University of Hong Kong (9380086), Innovation and Technology Bureau (ITS/497/18FP, GHP/021/18SZ), Guangdong‐Hong Kong‐Macao joint laboratory of optoelectronic and magnetic materials (2019B121205002), and Collaborative Research Fund grant (C5037‐18G) from the Research Grants Council of Hong Kong, Guangdong Major Project of Basic and Applied Basic Research (2019B030302007), and the Office of Naval Research (N00014‐20‐1‐2191). H.Y.W. thanks the financial support from the National Research Foundation (NRF) of Korea (NRF‐2016M1A2A2940911 and 2019R1A6A1A11044070). Y. L. is grateful for the support from the Hong Kong Scholars Program (XJ2019‐026), the Science and Technology Program of Shaanxi Province (2019JQ‐244), the Outstanding Youth Science and Technology Foundation of Xi'an University of Science and Technology (2019YQ3‐03).
Publisher Copyright:
© 2021 Wiley-VCH GmbH
PY - 2021/9/6
Y1 - 2021/9/6
N2 - Tuning molecular aggregation via structure design to manipulate the film morphology still remains as a challenge for polymer solar cells based on unfused non-fullerene acceptors (UF-NFAs). Herein, a strategy was developed to modulate the aggregation patterns of UF-NFAs by systematically varying the π-bridge (D) unit and central core (A’) unit in A−D-A’−D−A framework (A and D refer to electron-withdrawing and electron-donating moieties, respectively). Specifically, the quantified contents of H- or J-aggregation and crystallite disorder of three UF-NFAs (BDIC2F, BCIC2F, and TCIC2F) were analyzed via UV/Vis spectrometry and grazing incidence X-ray scattering. The results showed that the H-aggregate-dominated BCIC2F with less crystallite disorder exhibited a more favorable blend morphology with polymer donor PBDB-T (poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene)-co-(1,3-di(5-thiophene-2-yl)-5,7-bis(2-ethylhexyl)benzo[1,2-c:4,5-c']dithiophene-4,8-dione)]) relative the other two UF-NFAs, resulting in improved exciton dissociation and charge tranport. Consequently, photovoltaic devices based on BCIC2F delivered a promising power conversion efficiency of 12.4 % with an exceptionally high short-circuit current density of 22.1 mA cm−2.
AB - Tuning molecular aggregation via structure design to manipulate the film morphology still remains as a challenge for polymer solar cells based on unfused non-fullerene acceptors (UF-NFAs). Herein, a strategy was developed to modulate the aggregation patterns of UF-NFAs by systematically varying the π-bridge (D) unit and central core (A’) unit in A−D-A’−D−A framework (A and D refer to electron-withdrawing and electron-donating moieties, respectively). Specifically, the quantified contents of H- or J-aggregation and crystallite disorder of three UF-NFAs (BDIC2F, BCIC2F, and TCIC2F) were analyzed via UV/Vis spectrometry and grazing incidence X-ray scattering. The results showed that the H-aggregate-dominated BCIC2F with less crystallite disorder exhibited a more favorable blend morphology with polymer donor PBDB-T (poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene)-co-(1,3-di(5-thiophene-2-yl)-5,7-bis(2-ethylhexyl)benzo[1,2-c:4,5-c']dithiophene-4,8-dione)]) relative the other two UF-NFAs, resulting in improved exciton dissociation and charge tranport. Consequently, photovoltaic devices based on BCIC2F delivered a promising power conversion efficiency of 12.4 % with an exceptionally high short-circuit current density of 22.1 mA cm−2.
KW - aggregation
KW - morphology
KW - organic semiconductors
KW - photovoltaics
KW - solar cells
UR - http://www.scopus.com/inward/record.url?scp=85106439260&partnerID=8YFLogxK
U2 - 10.1002/cssc.202100746
DO - 10.1002/cssc.202100746
M3 - Article
C2 - 34037333
AN - SCOPUS:85106439260
VL - 14
SP - 3579
EP - 3589
JO - ChemSusChem
JF - ChemSusChem
SN - 1864-5631
IS - 17
ER -