Exciton diffusion length in some thermocleavable polythiophenes by the surface photovoltage method

Publication: Research - peer-reviewJournal article – Annual report year: 2011

View graph of relations

Poly-3-(2-methylhexyloxycarbonyl) dithiophene (P3MHOCT), poly-3-carboxydithiophene (P3CT) and polythiophene (PT) polymers were studied by optical and optoelectronic methods to find diffusion length as one of the important parameters characterizing them as candidates for solar cells. Their important property is that P3MHOCT can serve as a precursor which, after thermal annealing, converts into more rigid and insoluble P3CT and further thermal treatment produces native unsubstituted PT. Ellipsometric measurement yielded data on the thickness of the spin coated layers; absorption coefficients were obtained from transmittance and reflectance spectra. Our method of surface photovoltage extended to thin semiconducting layers was utilized for extraction of diffusion length of photogenerated excitons. Higher diffusion lengths in P3CT and PT materials as compared with that in P3MHOCT can probably be ascribed to the increase of the crystalline fraction. The highest diffusion length was found in P3CT polymer but its large resistivity represents a disadvantage in application in solar cells. Taking into account just these parameters, relatively low resistivity together with quite high diffusion length (13 ± 2 nm) predetermine the native polythiophene among the polymers studied in the present work as the best candidate for construction of solar cells.
Original languageEnglish
JournalSynthetic Metals
Publication date2012
Volume161
Issue23-24
Pages2727-2731
ISSN0379-6779
DOIs
StatePublished

Bibliographical note

We acknowledge the support of Ministry of Education, Youth and Sports of the Czech RepublicMSM 0021620834, Grant Agency of the Czech Republic (Grant No. 202/09/1206), the Danish Strategic Research Council (DSF 2104-05-0052 and 2104-07-0022), EUDP (j. nr. 64009-0050) and PV-ERA-NET (project acronym POLYSTAR).

CitationsWeb of Science® Times Cited: 2

Keywords

  • Polymer solar cells
Download as:
Download as PDF
Select render style:
APAAuthorCBEHarvardMLAStandardVancouverShortLong
PDF
Download as HTML
Select render style:
APAAuthorCBEHarvardMLAStandardVancouverShortLong
HTML
Download as Word
Select render style:
APAAuthorCBEHarvardMLAStandardVancouverShortLong
Word

ID: 6458176