Properties Of Thiophene Research Articles

UV protective textile: Experimental and DFT computational studies on the function of some metal complexes of hydrazide derivatives on cellulose fabrics

Ultraviolet (UV) radiation is harmful to the skin. Therefore, it capitalized on the properties of thiophene and pyridine derivatives to prepare new textile‐protective agents with improved UV protection factor (UPF) factor. This embodies the preparation and characterization of “2‐((3‐cyano‐4‐(4‐methoxyphenyl)‐6‐(thiophene‐2‐yl)pyridine‐2‐yl)oxy)acetohydrazide” (HZ) in complex with Ni(II), Cu(II), Zn(II), or Cd(II), using proton nuclear magnetic resonance (1H NMR), carbon‐13 nuclear magnetic resonance (13C NMR), X‐ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), and thermal analysis techniques. Characterization of cotton fabric‐based cellulose (CELL) in complex with the synthesized agents using FTIR spectroscopy, X‐ray spectroscopy, and scanning electron microscopy–energy dispersive X‐ray analysis (SEM–EDX) revealed deposition of the hydrazide and its metal complexes on the cellulosic fiber. Interestingly, cellulose complexation with Cu(II) was observed to have the highest value of the UPF. Computation of the reactivity indices using density functional theory (DFT) supports this finding, where the electrophilicity parameter of the modified fabric was found to correlate with the UPF wherein Cu(II) shows the highest value. The synthesized complexes could, therefore, provide lead structures for developing new UV‐protective agents with enhanced coating characteristics.

Synthesis and properties of thiophene- and quinoxaline-based random copolymers for organic photovoltaics

In this study, a series of polymers (denoted as PTQxFs) were prepared from random copolymers—poly[(5,8-(6,7-difluoro-2,3-dihexylquinoxaline))-alt-(2,5-thiophene)]-ran-[(2,5-(3-dodecylthiophene))-alt-(2,5-thiophene)]—via Pd(0)-catalyzed Stille polymerization using thiophene as the electron-rich unit and 6,7-difluoro-2,3-dihexylquinoxaline as an electron-deficient unit, which is newly synthesized by our group. This series of polymers were utilized for organic photovoltaics, and their absorption spectra, energy levels, and photovoltaic properties were investigated. The two fluorine atoms in the 6,7-difluoro-2,3-dihexylquinoxaline unit, exhibiting strong electron-withdrawing properties, enhanced the open-circuit voltage of solar cell devices due to the decrease of HOMO energy levels. With increasing number of 6,7-difluoro-2,3-dihexylquinoxaline units in the random copolymers, the HOMO energy levels decreased from −5.33 eV for PTQxF1 to −5.50 eV for PTQxF9, resulting in increased open-circuit voltage.

Effect of the thiophene and selenophene moiety in regular terpolymers on the performance of thin film transistors and polymer solar cells

We demonstrated the effective structural control of the conjugation length and various donor moieties using thiophene and selenophene derivatives in a regular terpolymer system and compared the properties with two copolymers of PDPP-SS and PDPP-TT. The three different terpolymers are composed of diketopyrrolopyrrole (DPP)-based polymers such as PDPP-TTS, PDPP-TSS, and PDPP-TTSS. The optical and electronic properties of these regular terpolymers can be precisely controlled by varying the conjugation length of the repeating unit and the composition ratio of the thiophene and selenophene moieties. It was found from the grazing incidence X-ray diffraction that PDPP-TTS and PDPP-TSS with different lengths of donor moieties exhibited mixed chain orientations in face-on and edge-on manners on the substrate. However, PDPP-TTSS showed edge-on chain orientation which is similar to the copolymers of PDPP-TT and PDPP-SS, and much improved charge-carrier mobility. Moreover, the enhanced power conversion efficiencies (PCEs) of polymer solar cells made of PDPP-TSS and PDPP-TTSS were observed to be 4.18 and 4.76%, respectively, owing to the higher composition of thiophene, which could be compensated by the properties of thiophene. As a result, the PCEs of regular terpolymers were markedly enhanced by inserting the thiophene moiety into the donor part of the DPP-based terpolymer, PDPP-SS.

Synthesis and Properties of Thiophene and Dithiin Functionalized Tetrathiafulvalenes

Syntheses of two analogues of tetrathiafulvalene (TTF), fused to 1,4-dithiin and thiophene rings, substituted with thiophene moieties, have been illustrated. The syntheses were accomplished through the reaction of a 1,8-diketone with phosphorus pentasulfide or Lawesson's reagent in boiling dry toluene. Conversion of the thioketones to their the oxo forms with mercury (II) acetate, was followed by self-coupling in freshly distilled boiling triethyl phosphite. Attempts for their electro-polymerizations through the thiophene groups at the peripherals were unsuccessful. Computational chemistry studies revealed that the thiophene groups did not exhibit enough spin densities to perform polymerization. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.

Influences of the electron donor groups on the properties of thiophene-(N-aryl)pyrrole-thiophene-based organic sensitizers

In this study, 1-(2,6-diisopropylphenyl)-2,5-di(2-thienyl)pyrrole-based metal-free organic dyes containing three different non planar electron donor groups such as methoxy or hexyloxy substituted triphenylamine and difluorenephenylamine were prepared in order to see the effect of electron donor groups on the opto-electrical properties and applied in dye-sensitized solar cells (DSSC). All three dyes showed broad absorption band in visible part of the solar spectrum (∼300nm–600nm). The dye (TPTDYE-3) containing sterically less hindered methoxy substituted triphenylamine was found to show relatively red shifted absorption compared to that of the dye (TPTDYE-4) containing hexyloxy substituted triphenylamine or the dye (TPTDYE-5) containing difluorenephenylamine. The optical band gaps of the three dyes were calculated to be 2.19eV, 2.22eV and 2.24eV, respectively, and the highest occupied molecular orbital (HOMO) energy levels of the three dyes were found to be located at 0.65V, 0.68V and 0.75V, respectively. The DSSC performance of each dye was investigated with and without coadsorbent. The maximum solar to electrical energy conversion efficiencies (η) of the DSSCs made from only sensitizer were 4.18%, 5.28% and 5.42% while those of the DSSCs made from sensitizer with coadsorbent were 5.47%, 5.58% and 5.63%, respectively.

Transient Absorption Investigation of the Photophysical Properties of Thiophene Linked [2H]-Chromenes

ABSTRACT The photophysical and photochemical properties of a bi-thiophene linked 2H-chromene are investigated by femtosecond and nanosecond transient absorption spectroscopy. The spectral characteristics and dynamics of the lowest excited singlet and triplet states are determined. The ring-opening reaction responsible for the photochromism is observed to occur in the S1 state with a time constant of about 150 ps in acetonitrile.

Synthesis and Photochromic Properties of Thiophene Linked [2H]-Chromenes

Successive coupling reactions (catalysed by Cu(I)/Pd(II) systems) between 8-bromo-3,3-diphenyl-[3H]naphtho[2,1-b]pyran, 2-methylbut-3-yn-2-ol and appropriate thiophene- or bithiophene halides afforded mono- or bichromophoric chromenes bearing a thienylethynyl or a bithienylethynyl group. Spectrokinetic study using flash photolysis conditions showed interesting photochromic properties regarding, especially, the “colorability” of the new compounds.

Syntheses and properties of thiophene- and pyrrole-based liquid crystalline small-bandgap conjugated polymers

We present syntheses and properties of thermotropic liquid crystalline conducting polymers with small-bandgaps. The polymers consist of benzenoid and quinonoid structures of polythiophene or polypyrrole backbone with liquid crystalline substituent, where phenylcyclohexyl moiety was adopted as a mesogenic core. Both kinds of polymers exhibited smectic liquid crystalline phases.