Selenium in diketopyrrolopyrrole-based polymers: Influence on electronic properties and charge carrier mobilities

Joydeep Dhar, Catherine Kanimozhi, Nir Yaccobi-Gross, Thomas Anthopoulos, Ulrike Salzner, Satish Patil*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

6 Scopus citations

Abstract

Diketopyrrolopyrrole (DPP)-based π-conjugated copolymers with thiophene have exceptionally high electron mobilities. This paper investigates electronic properties and charge carrier mobilities of selenophene containing analogues. Two new copolymers, with alternating thiophene DPP (TDPP) and selenophene DPP (SeDPP) units, were synthesized. Two side-chains, hexyl (Hex) and triethylene glycol (TEG) were employed, yielding polymers designated as PTDPPSeDPP-Hex and PTDPPSeDPP-TEG. Selenophene systems have smaller band gaps, with concomitant enhancement of the stability of the reduced state. For both polymers, ambipolar mobilities were observed in organic field-effect transistors (OFET). Grazing incidence X-ray diffraction (GIXD) data indicates preferential edge-on orientation of PTDPPSeDPP-TEG, which leads to superior charge transport properties of the TEG substituted polymer, as compared to its Hex analogue. Time-dependent-density functional theory (TDDFT) calculations corroborate the decrease in the optical band gap with the inclusion of selenophene. Ambipolar charge transport is rationalized by exceptionally wide conduction bands. ΔSCF calculations confirm the larger electron affinity, and therefore the greater stability, of the reduced form of the selenophene-containing DPP polymer in presence of chloroform.

Original languageEnglish (US)
Pages (from-to)817-827
Number of pages11
JournalIsrael Journal of Chemistry
Volume54
Issue number5-6
DOIs
StatePublished - Jan 1 2014

Keywords

  • band gap
  • charge carrier injection
  • copolymerization
  • diketopyrrolopyrrole
  • selenophene

ASJC Scopus subject areas

  • Chemistry(all)

Fingerprint

Dive into the research topics of 'Selenium in diketopyrrolopyrrole-based polymers: Influence on electronic properties and charge carrier mobilities'. Together they form a unique fingerprint.

Cite this