skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Structure, dynamics and power conversion efficiency correlations in a new low bandgap polymer : PCBM solar cell.

Abstract

Molecular packing structures and photoinduced charge separation dynamics have been investigated in a recently developed bulk heterojunction (BHJ) organic photovoltaic (OPV) material based on poly(thienothiophene-benzodithiophene) (PTB1) with a power conversion efficiency (PCE) of >5% in solar cell devices. Grazing incidence X-ray scattering (GIXS) measurements of the PTB1:PCBM ([6,6]-phenyl-C{sub 61}-butyric acid methyl ester) films revealed {pi}-stacked polymer backbone planes oriented parallel to the substrate surface, in contrast to the {pi}-stacked polymer backbone planes oriented perpendicular to the substrate surface in regioregular P3HT [poly(3-hexylthiophene)]:PCBM films. A {approx}1.7 times higher charge mobility in the PTB1:PCBM film relative to that in P3HT:PCBM films is attributed to this difference in stacking orientation. The photoinduced charge separation (CS) rate in the pristine PTB1:PCBM film is more than twice as fast as that in the annealed P3HT:PCBM film. The combination of a small optical gap, fast CS rate, and high carrier mobility in the PTB1:PCBM film contributes to its relatively high PCE in the solar cells. Contrary to P3HT:PCBM solar cells, annealing PTB1:PCBM films reduced the device PCE from 5.24% in the pristine film to 1.92% due to reduced interfacial area between the electron donor and the acceptor. Consequently, quantum yields of exciton generation and charge separationmore » in the annealed film are significantly reduced compared to those in the pristine film.« less

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC); National Science Foundation (NSF)
OSTI Identifier:
972186
Report Number(s):
ANL/CSE/JA-65297
Journal ID: ISSN 1520-6106; TRN: US201006%%982
DOE Contract Number:  
DE-AC02-06CH11357
Resource Type:
Journal Article
Journal Name:
J. Phys. Chem. C.
Additional Journal Information:
Journal Volume: 114; Journal Issue: 2 ; Jan. 21, 2010; Journal ID: ISSN 1520-6106
Country of Publication:
United States
Language:
ENGLISH
Subject:
14 SOLAR ENERGY; ANNEALING; BINDING ENERGY; CARRIER MOBILITY; EFFICIENCY; ELECTRONS; EXCITONS; HETEROJUNCTIONS; ORIENTATION; POLYMERS; SCATTERING; SOLAR CELLS; SUBSTRATES; VALENCE

Citation Formats

Guo, J, Liang, Y, Szarko, J, Lee, B, Son, H J, Rolczynski, B S, Yu, L, Chen, L X, Univ.of Chicago, and Northwestern Univ. Structure, dynamics and power conversion efficiency correlations in a new low bandgap polymer : PCBM solar cell.. United States: N. p., 2010. Web. doi:10.1021/jp909135k.
Guo, J, Liang, Y, Szarko, J, Lee, B, Son, H J, Rolczynski, B S, Yu, L, Chen, L X, Univ.of Chicago, & Northwestern Univ. Structure, dynamics and power conversion efficiency correlations in a new low bandgap polymer : PCBM solar cell.. United States. https://doi.org/10.1021/jp909135k
Guo, J, Liang, Y, Szarko, J, Lee, B, Son, H J, Rolczynski, B S, Yu, L, Chen, L X, Univ.of Chicago, and Northwestern Univ. 2010. "Structure, dynamics and power conversion efficiency correlations in a new low bandgap polymer : PCBM solar cell.". United States. https://doi.org/10.1021/jp909135k.
@article{osti_972186,
title = {Structure, dynamics and power conversion efficiency correlations in a new low bandgap polymer : PCBM solar cell.},
author = {Guo, J and Liang, Y and Szarko, J and Lee, B and Son, H J and Rolczynski, B S and Yu, L and Chen, L X and Univ.of Chicago and Northwestern Univ.},
abstractNote = {Molecular packing structures and photoinduced charge separation dynamics have been investigated in a recently developed bulk heterojunction (BHJ) organic photovoltaic (OPV) material based on poly(thienothiophene-benzodithiophene) (PTB1) with a power conversion efficiency (PCE) of >5% in solar cell devices. Grazing incidence X-ray scattering (GIXS) measurements of the PTB1:PCBM ([6,6]-phenyl-C{sub 61}-butyric acid methyl ester) films revealed {pi}-stacked polymer backbone planes oriented parallel to the substrate surface, in contrast to the {pi}-stacked polymer backbone planes oriented perpendicular to the substrate surface in regioregular P3HT [poly(3-hexylthiophene)]:PCBM films. A {approx}1.7 times higher charge mobility in the PTB1:PCBM film relative to that in P3HT:PCBM films is attributed to this difference in stacking orientation. The photoinduced charge separation (CS) rate in the pristine PTB1:PCBM film is more than twice as fast as that in the annealed P3HT:PCBM film. The combination of a small optical gap, fast CS rate, and high carrier mobility in the PTB1:PCBM film contributes to its relatively high PCE in the solar cells. Contrary to P3HT:PCBM solar cells, annealing PTB1:PCBM films reduced the device PCE from 5.24% in the pristine film to 1.92% due to reduced interfacial area between the electron donor and the acceptor. Consequently, quantum yields of exciton generation and charge separation in the annealed film are significantly reduced compared to those in the pristine film.},
doi = {10.1021/jp909135k},
url = {https://www.osti.gov/biblio/972186}, journal = {J. Phys. Chem. C.},
issn = {1520-6106},
number = 2 ; Jan. 21, 2010,
volume = 114,
place = {United States},
year = {2010},
month = {1}
}