Conjugated polymers based on modified benzo[1,2-b:4,5-b′]dithiophene and perylene diimide derivatives: Good optical properties and tunable electrochemical performance

Abstract

Three original conjugated polymers were devised and synthesized via the alternating conjugated polymerization of the electron-donating monomer of the modified benzo[1,2-b:4,5-b']dithiophene (BDT) and electronaccepting monomers of perylene diimide (PDI), dithienyl-perylene diimide (DTPDI) and dithienocoronene diimide (DTCDI), respectively. The synthesized conjugated polymers presented excellent thermal stability (T d >400 o C) as well as broad absorption in visible region and narrow gap of energy level (1.80 to 2.01 eV). Moreover, P(BDT-DTCDI) exhibited strong fluorescence properties ( =736 nm with excitation at 680 nm). According to the theoretical calculations, P(BDT-PDI) and P(BDT-DTPDI) displayed significant polymer backbone torsion (41.44 o and 39.64 o ), and P(BDT-DTCDI) had highly coplanar backbone with negligible angle between BDT and DTCDI. The results indicated that P(BDT-DTCDI) had potential applications in the fields of organic thin-film transistors (OTFTs) and fluorescence materials, and P(BDT-PDI) and P(BDT-DTPDI) could be used as a stable n-type semiconductor for polymer solar cells.

Effect of thiophene spacers in benzodithiophene‐based polymers for organic electronics

“…Benzo[1,2‐ b :4,5‐ b ′]‐dithiophene (BDT) based polymers have gained attention among the organic semiconducting materials due to their good optoelectronic properties and their ability to be modified to tune their solubility and band gap . BDT polymers can be used in organic field‐effect transistors (OFETs), sensors, and organic photovoltaic applications, such as solar cells and organic light emitting diodes (OLEDs) .…”

“…BDT polymers can be used in organic field‐effect transistors (OFETs), sensors, and organic photovoltaic applications, such as solar cells and organic light emitting diodes (OLEDs) . BDT polymers are a group of widely studied fused‐ring polymers . The ability to undergo effective charge transport with extended planar π conjugated backbone created by the fused ring system make BDT polymers prospective materials in semiconducting applications .…”

“…BDT polymers are a group of widely studied fused‐ring polymers . The ability to undergo effective charge transport with extended planar π conjugated backbone created by the fused ring system make BDT polymers prospective materials in semiconducting applications . The ability of fused ring systems to undergo better π–π stacking due to larger area of overlap between aromatic rings facilitate intermolecular charge hopping between the chains and contribute to the charge transport enhancement, in addition to the intramolecular charge delocalization through the backbone .…”

“…The ability of fused ring systems to undergo better π–π stacking due to larger area of overlap between aromatic rings facilitate intermolecular charge hopping between the chains and contribute to the charge transport enhancement, in addition to the intramolecular charge delocalization through the backbone . The processability from organic solvents and effective packing of the polymer chains without adversely affecting the planarity of the polymer backbone can be obtained by side group engineering of BDT units at 4th and 8th positions of the BDT core . This can be further used to tune the band gap of the resulting functionalized materials .…”

Microwave-Assisted Classic Ullmann C–C Coupling Polymerization for Acceptor-Acceptor Homopolymers

“…Polymeric semiconductors are emerging as crucial components for state-of-the-art opto-electronic technologies, including organic thin film transistors (TFTs), organic photovoltaics (OPV) and organic photodetectors (OPDs), due to their tunable energy levels, potentially low cost manufacturing, and solution-processability [1,2,3,4]. To tune the energy levels and enhance intramolecular charge transfer, the donor-acceptor (D-A) strategy has been used to construct conjugated polymers by various transition metal-mediated aryl coupling methodologies, including Stille coupling and Suzuki coupling reactions [5,6,7,8,9,10,11,12]. Although D-A type copolymers have demonstrated great success in the area of organic electronics, they still suffered from complicated structures and costly synthetic routes.…”