Alkyl-end phenanthroimidazole modification of benzotriazole based conjugated polymers for optoelectronic applications

Abstract

A new triazoloquinoxaline and benzodithiophene based copolymer was synthesized to investigate its electrochemical, optical and photovoltaic behaviors. According to the polymer design, combination of two acceptor units (benzotriazole and quinoxaline) which contribute imine bonds to the structure and a triazoloquinoxaline unit for enhancing electron accepting ability was pursued. As a result of electrochemical studies, the copolymer PTQBDT has a low lying HOMO energy level as −5.23 eV which increases the chemical stability of the resulting polymer and leads to a higher V oc . In addition, the copolymer has an ambipolar character with two well-defined redox couples in the n-doped state and multichromic behavior. In the context of optical studies, PTQBDT has wide absorption range in the visible region with a tail in the NIR region, which yields a low band gap of 1.20 eV. Organic photovoltaic devices were designed using PTQBDT (the electron donor) and PC 71 BM (the electron acceptor) for the preliminary studies. The resulting device exhibits a power conversion efficiency of 2.0% with a current density of 8.07 mA cm −2 , an open-circuit voltage of 0.45 V, and a fill factor of 55%. The carrier mobility of the PTQBDT was calculated as 3.00 × 10 −3 cm 2 V −1 s −1 via space-charge-limited current (SCLC) method.

Ionic liquid-functionalized poly-N-phenylpyrrole coated on a NiTi alloy substrate for highly efficient solid-phase microextraction

“…Conductive polymers (CPs) are a class of advanced materials with a highly conjugated π-electron system along a polymer backbone and have been used in many different fields. 22,26,27 Due to their unique electrical properties and extensive conjugation as well as diverse functional groups and simple synthesis technology, CPs have been attracting growing interest in SPME. 22–25 CPs such as polyaniline, polypyrrole, polythiophene and their derivatives as fiber coatings of SPME display different extraction efficiencies for compounds because of their inherent and extraordinary multifunctionality including hydrophobic, acid–base and π–π interactions, ion-exchange, polar functional groups and hydrogen bonding.…”