Plastic Solar Cells Based on Fluorenone-Containing Oligomers and Regioregular Alternate Copolymers

Oligomers and regioregular copolymers based on fluorenone subunits are synthesized and used in bulk‐heterojunction photovoltaic cells. These are 2,7‐bis(5‐[(E)‐1,2‐bis(3‐octylthien‐2‐yl)ethylene])‐fluoren‐9‐one (TVF), the product of its oxidative polymerization, that is, (poly[(5,5′‐(bis‐(E)‐1,2‐bis...

Full description

Saved in:
Bibliographic Details
Published in:Advanced functional materials 2005-09, Vol.15 (9), p.1547-1552
Main Authors: Demadrille, R., Firon, M., Leroy, J., Rannou, P., Pron, A.
Format: Article
Language:English
Subjects:
Chemical Sciences
Conjugated polymers
Copolymers
Engineering Sciences
Fluorenone
Fullerenes
Heterojunctions
Material chemistry
Organic chemistry
Photovoltaic devices
Polymers
Solar cells
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Oligomers and regioregular copolymers based on fluorenone subunits are synthesized and used in bulk‐heterojunction photovoltaic cells. These are 2,7‐bis(5‐[(E)‐1,2‐bis(3‐octylthien‐2‐yl)ethylene])‐fluoren‐9‐one (TVF), the product of its oxidative polymerization, that is, (poly[(5,5′‐(bis‐(E)‐1,2‐bis(3‐octylthien‐2‐yl)ethylene]‐alt‐(2,7‐fluoren‐9‐one)]) (PTVF), and an alternate copolymer of fluoren‐9‐one and di‐n‐alkylbithiophene, namely poly[(5,5′‐(3,3′‐di‐n‐octyl‐2,2′‐bithiophene))‐alt‐(2,7‐fluoren‐9‐one)] (PDOBTF). The interpenetrating networks of active layers consisting of these new compounds as electron donors and of methanofullerene [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) as an acceptor exhibit an extended absorption band in the visible part of the spectrum with an absorption edge close to 700 nm. The external power conversion efficiencies (EPCEs) and the external quantum efficiency of the various TVF‐, PTVF‐, and PDOBTF‐based photovoltaic cells have been determined. EPCE values of up to 1 % have been achieved, which demonstrate the potential of fluorenone‐based materials in solar cells. It has also been demonstrated that fluorenone subunits are efficient photon absorbers for the conversion. Interestingly, some cell parameters such as, for example, the fill factor, have been improved as compared to photovoltaic cells with a “classical” poly[2‐methoxy‐5‐(3′,7′‐dimethyloctyloxy)‐1,4‐phenylenevinylene]/PCBM active layer, fabricated and studied under the same experimental conditions. Oligomers and regioregular copolymers based on fluorenone subunits (see Figure) have been synthesized and used in polymer/fullerene bulk‐heterojunction photovoltaic cells (see Figure). Incident photon‐to‐current conversion efficiency experiments show that the fluorenone units are efficient in converting photons to electrons. Some of the devices exhibit efficiencies (ηext) of up to 1.1 %.
ISSN:1616-301X
1616-3028
DOI:10.1002/adfm.200500117