Solid-State Organization and Ambipolar Field-Effect Transistors of Benzothiadiazole-Cyclopentadithiophene Copolymer with Long Branched Alkyl Side Chains.

The solid-state organization of a benzothiadiazole-cyclopentadithiophene copolymer with long, branched decyl-tetradecyl side chains () is investigated. The substituents are sterically demanding and increase the π-stacking distance to 0.40 nm from 0.

Columnar self-assembly in electron-deficient heterotriangulenes.

A series of soluble carbonyl-bridged heterotriangulenes, in which flexible n-dodecyl chains are attached through different spacers to the planar nitrogen-centered polycyclic core, have been synthesized. The introduction of triisopropylsilylethynyl moieties enabled, for the first time, the characterization of single-crystal columnar packing of a substituted heterotriangulene by X-ray crystallography. Electrochemical studies disclosed the carbonyl-bridged heterotriangulene core as a reasonably strong acceptor for a reversible two-electron transfer.

Synthesis and characterization of anthracene derivative for organic field-effect transistor fabrication.

Here we report on the synthesis and characterization of anthracene derivative for solution processable organic field-effect transistors. The transistor devices with bottom-contact geometry provided a maximum field-effect mobility of 3.74 x 10(-4) cm2 V(-1) s(-1) as well as current on/off ratio of 5.

Molecular triangles: synthesis, self-assembly, and blue emission of cyclo-7,10-tris-triphenylenyl macrocycles.

A set of cyclo-7,10-tris-triphenylenyl macrocycles have been prepared by a Yamamoto cyclotrimerization protocol. In these novel macrocycles, three triphenylene units are covalently linked to each other, resulting in the formation of triangular-shaped molecules. The fully planar derivative revealed pronounced self-assembly behavior.

Fluorenyl hexa-peri-hexabenzocoronene-dendritic oligothiophene hybrid materials: synthesis, photophysical properties, self-association behaviour and device performance.

Apart from molecular properties, intermolecular forces play a vital role in defining the performance of organic electronic devices. This is particularly relevant in bulk heterojunction (BHJ) solar cells in which the arrangement of electron-donor and -acceptor materials into distinct crystalline phases of ideal size and distribution can lead to better power conversion efficiencies. In this study, a series of fluorenyl hexa-peri-hexabenzocoronenes (FHBC) decorated with thiophene dendrons (DOT) of variable size was obtained by using a convergent synthetic approach.

Ultrahigh mobility in polymer field-effect transistors by design.

In this article, the design paradigm involving molecular weight, alkyl substituents, and donor-acceptor interaction for the poly[2,6-(4,4-bis-alkyl-4H-cyclopenta[2,1-b;3,4-b']-dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (cyclopentadithiophene-benzothiadiazole) donor-acceptor copolymer (CDT-BTZ) toward field-effect transistors (FETs) with ultrahigh mobilities is presented and discussed. It is shown that the molecular weight plays a key role in improving hole mobilities, reaching an exceptionally high value of up to 3.3 cm(2) V(-1) s(-1).

Electronic properties and supramolecular organization of terminal bis(alkylethynyl)-substituted benzodithiophenes.

Benzodithiophene (BDT) was symmetrically bisubstituted in the terminal positions with five different alkynes C≡C-(C(n)H(2n+1)) with n = 4, 6, 8, 10, 12. The materials were characterized as potential materials for field-effect transistor applications. Electrochemical measurements in solution and photophysical measurements in solution and in the solid state, together with UV photoelectron spectroscopy in air and quantum-chemical calculations, elucidate the nature of the frontier orbitals and of the excited states as well as their deactivation pathways.