Related Experiment Video
Updated: Jun 14, 2026

Effect of Bending on the Electrical Characteristics of Flexible Organic Single Crystal-based Field-effect Transistors
Published on: November 7, 2016
Acetylenic spacers in phenylene end-substituted oligothiophene core for highly air-stable organic field-effect
Abdou Karim Diallo1, Christine Videlot-Ackermann, Philippe Marsal
1Centre Interdisciplinaire de Nanoscience de Marseille, CNRS UPR 3118, Campus Luminy, Aix Marseille Université, Case 913, 13288 Marseille Cedex 09, France.
Abstract:
Two thiophene-phenylene semiconductors, bis(2-phenylethynyl) end-substituted oligothiophenes (diPhAc-nTs, n = 2, 3), were synthesized and studied with respect to their optical, electrochemical, structural and electrical properties. The optical and electrochemical properties of the oligomers in solution were investigated by UV-vis absorption and photoluminescence spectroscopies, and cyclic voltammetry. High vacuum evaporated thin films were investigated by optical absorption, X-ray diffraction and AFM, and implemented as p-type semiconducting layers into organic thin-film transistors (OTFTs). A comparative study in solution and in the solid state with distyryl-oligothiophenes (DSnTs, n = 2, 3) reveals the great influence of acetylenic (-C[triple bond]C-) vs. olefinic (-C=C-) spacers in thiophene-phenylene derivatives on electronic structure, physical properties, and device efficiencies. Substituting olefinic for acetylenic pi-spacers in terthiophene-based conjugated semiconductors leads to one of incontrovertible attributes of OTFTs for low cost applications, a high mobility at low substrate temperature (T(sub)) i.e. typically 25 degrees C. Fine-tuning in the HOMO/LUMO levels by reducing the HOMO level introduces increased air-oxidation strength of thin films where OTFTs provide exactly the same hole mobility value after 100 days in air. All the results suggested that introduction of carbon-carbon triple bonds provided an efficient route to highly air-stable organic thin film transistors.
More Related Videos
Related Concept Videos
π Electron Effects on Chemical Shift: Overview
Radical Reactivity: Steric Effects
Along with electronic factors, steric factors also account...
Stability of Substituted Cyclohexanes
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
ortho–para-Directing Activators: –CH3, –OH, –⁠NH2, –OCH3
Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
π Electron Effects on Chemical Shift: Aromatic and Antiaromatic Compounds

