2D π-conjugated benzo[1,2-b:4,5-b']dithiophene- and quinoxaline-based copolymers for photovoltaic applications
Journal article, 2013

Two medium gap semiconducting polymers, P(1)-Q-BDT-4TR and P(2)-FQ-BDT-4TR, based on alternate units of alkyl-dithiophene substituted benzodithiophene (BDT) and quinoxaline units (without or with fluorine substitution), are synthesized and fully characterized. The polymers exhibit optical and electrical properties favorable for being employed as donors in BHJ OPV devices, such as: absorption spectra extending up to around 720 nm for a high solar spectrum coverage, deep lying HOMO energy levels for a high device open circuit voltage and LUMO energy levels higher than those of PC61BM and PC71BM for an efficient exciton dissociation. In particular, the presence of alkyl-dithiophene side chains allows us to obtain a high 2D π-conjugation which promotes red shifted absorption profiles, low HOMO energy levels (<−5.6 eV) and enhanced environmental and thermal stability. Moreover, the introduction of the fluorine atom in the polymer backbone allows us to obtain efficient OPV devices, based on as-cast P(2)-FQ-BDT-4TR:PC61BM blend, showing a JSC of −10.2 mA cm−2, VOC of 0.90 V, FF of 58% and PCE of 5.3%, without the need for any additional thermal treatment.

Author

Margherita Bolognesi

Laboratory MIST E-R

Desta Antenehe Gedefaw

Chalmers, Chemical and Biological Engineering, Polymer Technology

Dongfeng Dang

Chalmers, Chemical and Biological Engineering, Polymer Technology

Patrik Henriksson

Chalmers, Chemical and Biological Engineering, Polymer Technology

Wenliu Zhuang

Chalmers, Chemical and Biological Engineering, Polymer Technology

Marta Tessarolo

Istituto Per Lo Studio Dei Materiali Nanostrutturati, Rome

Ergang Wang

Chalmers, Chemical and Biological Engineering, Polymer Technology

Michele Muccini

Istituto Per Lo Studio Dei Materiali Nanostrutturati, Rome

Mirko Seri

Istituto per la Sintesi Organica e la Fotoreattività

Mats Andersson

Chalmers, Chemical and Biological Engineering, Polymer Technology

RSC Advances

2046-2069 (ISSN)

Vol. 3 46 24543-24552

SUstainable Novel FLexible Organic Watts Efficiently Reliable (SUNFLOWER)

European Commission (FP7), 2011-10-01 -- 2016-03-31.

Subject Categories

Materials Engineering

Physical Sciences

Environmental Engineering

Chemical Engineering

Electrical Engineering, Electronic Engineering, Information Engineering

Chemical Sciences

Infrastructure

C3SE (Chalmers Centre for Computational Science and Engineering)

Areas of Advance

Materials Science

DOI

10.1039/C3RA44238A

More information

Latest update

9/6/2018 1