Syntheses, electrochemical and spectroelectrochemical characterization of benzothiadiazole and benzoselenadiazole based random copolymers


Kutkan S., Goker S., Hacioglu S. O. , TOPPARE L. K.

JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY, vol.53, no.8, pp.475-483, 2016 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 53 Issue: 8
  • Publication Date: 2016
  • Doi Number: 10.1080/10601325.2016.1189280
  • Journal Name: JOURNAL OF MACROMOLECULAR SCIENCE PART A-PURE AND APPLIED CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.475-483
  • Keywords: Benzothiadiazole, benzoselenadiazole, carbazole, fluorene, silafluorene, electrochromism, donor-acceptor type, random copolymers, PI-CONJUGATED SYSTEMS, LOW-BANDGAP POLYMERS, SOLAR-CELLS, OPTICAL-PROPERTIES, PHOTOVOLTAIC APPLICATIONS, OPTOELECTRONIC PROPERTIES, GAP POLYMERS, DERIVATIVES, THIOPHENE, FLUORENE

Abstract

Three novel donor-acceptor-donor type random copolymers based on benzothiadiazole (BTh) and benzoselenadiazole (BSe) were synthesized via Pd (0) catalyzed Suzuki polycondensation reaction. The two acceptor units were coupled with electron rich moieties which are carbazole (CZ), fluorene (FL) and silafluorene (SiFL). Monomers were characterized using H-1 and C-13-NMR spectroscopy. The number and weight average molecular weights of the polymers were calculated using gel permeation chromatography (GPC). All three polymers were electrochemically and spectroelectrochemically characterized. PBThBSeCZ, PBThBSeFL and PBThBSeSiFL showed only p-dopable character and their doping/dedoping potentials were determined as 1.4V/1.2V, 1.53V/1.27V and 1.8V/1.3V, respectively. Corresponding HOMO energy levels were calculated as -5.85eV, -6.05eV and -6.15eV whereas LUMO energy levels were found to be -3.67eV, -3.84eV and -3.77eV, respectively. PBThBSeCZ had lower HOMO level and band gap than PBThBSeFL and PBThBSeSiFL due to its increased electron donating capability of nitrogen atom in carbazole unit.