Abstract
Achieving efficient polymer solar cells (PSCs) requires a structurally optimal donor-acceptor heterojunction morphology. Here we report the combined experimental and theoretical characterization of a benzodithiophene-benzothiadiazole donor polymer series (PBTZF4-R; R = alkyl substituent) blended with the non-fullerene acceptor ITIC-Th and analyze the effects of substituent dimensions on blend morphology, charge transport, carrier dynamics, and PSC metrics. Varying substituent dimensions has a pronounced effect on the blend morphology with a direct link between domain purity, to some extent domain dimensions, and charge generation and collection. The polymer with the smallest alkyl substituent yields the highest PSC power conversion efficiency (PCE, 11%), reflecting relatively small, high-purity domains and possibly benefiting from "matched" donor polymer-small molecule acceptor orientations. The distinctive morphologies arising from the substituents are investigated using molecular dynamics (MD) simulations which reveal that substituent dimensions dictate a well-defined set of polymer conformations, in turn driving chain aggregation and, ultimately, the various film morphologies and mixing with acceptor small molecules. A straightforward energetic parameter explains the experimental polymer domain morphological trends, hence PCE, and suggests strategies for substituent selection to optimize PSC materials morphologies.
| Original language | English |
|---|---|
| Journal | Journal of the American Chemical Society |
| DOIs | |
| Publication status | Accepted/In press - Jan 1 2019 |
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ASJC Scopus subject areas
- Catalysis
- Chemistry(all)
- Biochemistry
- Colloid and Surface Chemistry
Cite this
Photovoltaic Blend Microstructure for High Efficiency Post-Fullerene Solar Cells. To Tilt or Not to Tilt? / Wang, Gang; Swick, Steven M.; Matta, Micaela; Mukherjee, Subhrangsu; Strzalka, Joseph W.; Logsdon, Jenna Leigh; Fabiano, Simone; Huang, Wei; Aldrich, Thomas J.; Yang, Tony; Timalsina, Amod; Powers-Riggs, Natalia; Alzola, Joaquin M.; Young, Ryan M.; Delongchamp, Dean M.; Wasielewski, Michael R.; Kohlstedt, Kevin L.; Schatz, George C.; Melkonyan, Ferdinand S.; Facchetti, Antonio; Marks, Tobin J.
In: Journal of the American Chemical Society, 01.01.2019.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Photovoltaic Blend Microstructure for High Efficiency Post-Fullerene Solar Cells. To Tilt or Not to Tilt?
AU - Wang, Gang
AU - Swick, Steven M.
AU - Matta, Micaela
AU - Mukherjee, Subhrangsu
AU - Strzalka, Joseph W.
AU - Logsdon, Jenna Leigh
AU - Fabiano, Simone
AU - Huang, Wei
AU - Aldrich, Thomas J.
AU - Yang, Tony
AU - Timalsina, Amod
AU - Powers-Riggs, Natalia
AU - Alzola, Joaquin M.
AU - Young, Ryan M.
AU - Delongchamp, Dean M.
AU - Wasielewski, Michael R.
AU - Kohlstedt, Kevin L.
AU - Schatz, George C.
AU - Melkonyan, Ferdinand S.
AU - Facchetti, Antonio
AU - Marks, Tobin J.
PY - 2019/1/1
Y1 - 2019/1/1
N2 - Achieving efficient polymer solar cells (PSCs) requires a structurally optimal donor-acceptor heterojunction morphology. Here we report the combined experimental and theoretical characterization of a benzodithiophene-benzothiadiazole donor polymer series (PBTZF4-R; R = alkyl substituent) blended with the non-fullerene acceptor ITIC-Th and analyze the effects of substituent dimensions on blend morphology, charge transport, carrier dynamics, and PSC metrics. Varying substituent dimensions has a pronounced effect on the blend morphology with a direct link between domain purity, to some extent domain dimensions, and charge generation and collection. The polymer with the smallest alkyl substituent yields the highest PSC power conversion efficiency (PCE, 11%), reflecting relatively small, high-purity domains and possibly benefiting from "matched" donor polymer-small molecule acceptor orientations. The distinctive morphologies arising from the substituents are investigated using molecular dynamics (MD) simulations which reveal that substituent dimensions dictate a well-defined set of polymer conformations, in turn driving chain aggregation and, ultimately, the various film morphologies and mixing with acceptor small molecules. A straightforward energetic parameter explains the experimental polymer domain morphological trends, hence PCE, and suggests strategies for substituent selection to optimize PSC materials morphologies.
AB - Achieving efficient polymer solar cells (PSCs) requires a structurally optimal donor-acceptor heterojunction morphology. Here we report the combined experimental and theoretical characterization of a benzodithiophene-benzothiadiazole donor polymer series (PBTZF4-R; R = alkyl substituent) blended with the non-fullerene acceptor ITIC-Th and analyze the effects of substituent dimensions on blend morphology, charge transport, carrier dynamics, and PSC metrics. Varying substituent dimensions has a pronounced effect on the blend morphology with a direct link between domain purity, to some extent domain dimensions, and charge generation and collection. The polymer with the smallest alkyl substituent yields the highest PSC power conversion efficiency (PCE, 11%), reflecting relatively small, high-purity domains and possibly benefiting from "matched" donor polymer-small molecule acceptor orientations. The distinctive morphologies arising from the substituents are investigated using molecular dynamics (MD) simulations which reveal that substituent dimensions dictate a well-defined set of polymer conformations, in turn driving chain aggregation and, ultimately, the various film morphologies and mixing with acceptor small molecules. A straightforward energetic parameter explains the experimental polymer domain morphological trends, hence PCE, and suggests strategies for substituent selection to optimize PSC materials morphologies.
UR - http://www.scopus.com/inward/record.url?scp=85071639432&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85071639432&partnerID=8YFLogxK
U2 - 10.1021/jacs.9b03770
DO - 10.1021/jacs.9b03770
M3 - Article
C2 - 31379156
AN - SCOPUS:85071639432
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
ER -