Nitrile-substituted thienyl and phenyl units as building blocks for high performance n-type polymer semiconductors

Abstract

Two novel polymers PDPP3T-CN and PDPPTPT-CN containing nitrile-substituted thienyl and phenyl units were designed and synthesized. The influence of nitrile groups on the electronic properties and charge-carrier transport of the polymers was thoroughly investigated and highlighted by comparing with the corresponding non-nitrile substituted polymers. Experimental results showed the introduction of nitrile groups lowered the HOMO and LUMO energy levels of polymers about 0.3 eV and 0.2 eV, respectively. Thin film transistors characteristics displayed both polymers exhibited electrondominated ambipolar behavior in ambient condition. The highest electron/hole mobilities were 0.18/0.0083 cm 2 V -1 s -1 for PDPPTPT-CN and 0.09/0.0017 cm 2 V -1 s -1 for PDPP3T-CN, one of the highest electron mobility for DPP-based polymers measured in ambient condition with bottom-gate/top-contact device configuration.

Insight into High-Performance Conjugated Polymers for Organic Field-Effect Transistors

“…Li et al reported the synthesis of dicyanated thiophene (2CNT) and dicyanated benzene (2CNPh). 69 Two copolymers (P34 and P35) of DPP and 2CNT or 2CNPh were synthesized. P34 and P35 showed low-lying LUMO energy levels of À3.80 and À3.71 eV, respectively.…”

New copolymers with thieno[3,2‐b]thiophene or dithieno[3,2‐b:2′,3′‐d]thiophene units possessing electron‐withdrawing 4‐cyanophenyl groups: Synthesis and photophysical, electrochemical, and electroluminescent properties

“…Commercial TLC (Merck TLC Silica Gel 60 F 254 ) was used to follow the reaction course and/or find out the eluent (mobile phase) for the column chromatography. 1 H and C NMR spectra of low‐molecular weight compounds were recorded with a Varian model NMR 500 or 600 MHz in deuterated chloroform (CDCl 3 ) or dimethyl sulfoxide (DMSO‐ d 6 ) using tetramethylsilane as an internal standard. 1 H NMR and C NMR spectra of polymers were measured in deuterated tetrahydrofuran (THF‐ d 8 ), chloroform or trifluoroacetic acid (CF 3 COOD) with an upgraded Bruker Avance DPX‐300 spectrometer at 300.13 and 75.45 MHz, respectively, using hexamethyldisiloxane as an internal standard.…”

“…1 H and C NMR spectra of low‐molecular weight compounds were recorded with a Varian model NMR 500 or 600 MHz in deuterated chloroform (CDCl 3 ) or dimethyl sulfoxide (DMSO‐ d 6 ) using tetramethylsilane as an internal standard. 1 H NMR and C NMR spectra of polymers were measured in deuterated tetrahydrofuran (THF‐ d 8 ), chloroform or trifluoroacetic acid (CF 3 COOD) with an upgraded Bruker Avance DPX‐300 spectrometer at 300.13 and 75.45 MHz, respectively, using hexamethyldisiloxane as an internal standard. FT IR spectra were recorded with a Thermo Nicolet 6700 FT‐IR or Perkin‐Elmer Paragon 1000 PC Fourier transform infrared spectrometer by means of diamond attenuated total reflection (ATR).…”

“…These materials are used in the design and construction of magnetic and photosensitive receptors, sensors, electrochromic devices (ECD), organic light‐emitting diodes (OLED), field effect transistors (FET), and solar cells . Cyano‐substituted polymers are also of interest due to the electron‐deficient CN group for optoelectronic and sensing applications . The introduction of cyano groups into the polymer backbone usually lowers its LUMO level, leading to an increased electron affinity and decreased band gap energy.…”

Synthesis and opto‐electronic properties of functionalized pyrimidine‐based conjugated polymers

“…Recently, D‐A conjugated polymers made of combinations of electron rich donor (D) moieties, and electron deficient acceptor (A) moieties have been extensively reported. Incorporating electron‐deficient heteroaryl moieties, such as aromatic diimides, halogenated aromatic diimides, and cyano and/or carbonyl aromatic ring, into the polymer backbone reduces the LUMO level and thus facilitates electron injection and transport . Among these moieties, polymer incorporating electron deficient pyrimidine and its derivatives as the electron‐accepting unit possess high reactivity and potential for substituent modification.…”