Title
Molecular Rectification in Conjugated Block Copolymer Photovoltaics
Date Issued
21 April 2016
Access level
metadata only access
Resource Type
journal article
Author(s)
Grieco C.
Aplan M.
Rimshaw A.
Lee Y.
Le T.
Zhang W.
Wang Q.
Milner S.
Asbury J.
Pennsylvania State University
Publisher(s)
American Chemical Society
Abstract
We investigate the influence that covalent linkage of electron donating and accepting blocks in high performance fully conjugated block copolymer photovoltaics has on charge generation and recombination using ultrafast mid-infrared transient absorption spectroscopy. We show that block copolymer architectures containing a conjugated bridge between the donor and acceptor groups can be used to form ordered mesoscale morphologies that lead to improved photovoltaic performance without enhancing charge recombination. Judicious placement of an electron-rich moiety in the electron accepting block of the block copolymer creates a donor-bridge-acceptor architecture that slows intramolecular charge transfer across the covalent linkage. Charge recombination in such donor-bridge-acceptor block copolymer films proceeds at the same rate as it does in their corresponding homopolymer blends for which the donor and acceptor blocks are not covalently linked, indicating that recombination is dominated by intermolecular charge transfer in both systems. The electrical and morphological properties of functional block copolymer photovoltaics are correlated with their underlying charge generation and recombination kinetics, permitting us to identify key design rules for further improvements in the power conversion efficiency of fully conjugated block copolymer solar cells.
Start page
6978
End page
6988
Volume
120
Issue
13
Language
English
OCDE Knowledge area
Ingeniería química Química física
Scopus EID
2-s2.0-84964452796
Source
Journal of Physical Chemistry C
ISSN of the container
19327447
Sponsor(s)
Financial support from the Office of Naval Research under Grant N000141410532 is gratefully acknowledged. The Advanced Light Source is an Office of Science User Facility operated for the U.S. Department of Energy Office of Science by Lawrence Berkeley National Laboratory and is supported by the U.S. Department of Energy under Contract DE-AC02-05CH11231.
Sources of information: Directorio de Producción Científica Scopus