Anthradithiophene chromophores are found in many current high-performance organic semiconductors, even though these materials are typically synthesized as an inseparable mixture of syn and anti isomers. Recent syntheses of pure syn anthradithiophenes have shown no improvement in performance for the more homogeneous system, but similar studies on the pure anti isomer have not been reported. In this work, a simple protocol is described to prepare the pure anti isomer of fluorinated, functionalized anthradithiophenes, and perform detailed analysis of the intermolecular interactions in the crystal that yield increased density and closer chromophore contacts. Studies of the charge-transport properties of these pure isomers, compared to the isomeric mixtures, suggest that the benefit of isomer purity is not consistent; in the syn case, there was minimal difference between the pure isomer and the mixture, while for the anti isomer mobility improved nearly twofold. Analysis of disorder in the crystals suggests a reason for this difference in performance.

The astounding electronic performance of acenes such as tetracene and pentacene (and their heteroaromatic counterparts) stands to revolutionize the field of organic electronics, promising novel consumer electronics for power generation and information display in lightweight, flexible form factors. These results have rekindled interest in acenes larger than pentacene, to determine how electronic properties are further altered by extending conjugation. This research has had to encompass many fundamental studies, as even the simple nature of aromaticity in larger acenes is still a controversial topic. Further, the reactivity of acenes toward oligomerization or oxidation becomes significant in larger acenes, while the diminishing solubility complicates isolation and characterization. This article surveys recent works describing the nature of aromaticity and reactivity in larger acenes, methods used to prepare parent acenes larger than pentacene, and functionalization approaches to soluble, reasonably stable large acenes.

A chemically coupled polymer layer is introduced onto inorganic oxide dielectrics from a dilute chlorosilane-terminated polystyrene (PS) solution. As a result of this surface modification, hydrophilic-oxide dielectrics gain hydrophobic, physicochemically stable properties. On such PS-coupled SiO₂ or AlO_x dielectrics, various vacuum- and solution-processable organic semiconductors can develop highly ordered crystalline structures that provide higher field-effect mobilities (μ_FETs) than other surface-modified systems, and negligible hysteresis in organic field-effect transistors (OFETs). In particular, the use of PS-coupled AlO_x nanodielectrics enables a solution-processable triethylsilylethynyl anthradithiophene OFET to operate with μ_FET ∼ 1.26 cm² V⁻¹ s⁻¹ at a gate voltage below –1 V. In addition, a complementary metal-oxide semiconductor-like organic inverter with a high voltage gain of approximately 32 was successfully fabricated on a PS-coupled SiO₂ dielectric.

Organic semiconductors have been the subject of intensive academic and commercial interest over the past two decades, and successful commercial devices incorporating them are slowly beginning to enter the market. Much of the focus has been on the development of hole transporting, or p-type, semiconductors that have seen a dramatic rise in performance over the last decade. Much less attention has been devoted to electron transporting, or so called n-type, materials, and in this paper we focus upon recent developments in several classes of n-type materials and the design guidelines used to develop them.

Acenes have long been the subject of intense study because of the unique electronic properties associated with their π-bond topology. Recent reports of impressive semiconductor properties of larger homologues have reinvigorated research in this field, leading to new methods for their synthesis, functionalization, and purification, as well as for fabricating organic electronic components. Studies performed on high-purity acene single crystals revealed their intrinsic electronic properties and provide useful benchmarks for thin film device research. New approaches to add functionality were developed to improve the processability of these materials in solution. These new functionalization strategies have recently allowed the synthesis of acenes larger than pentacene, which have hitherto been largely unavailable and poorly studied, as well as investigation of their associated structure/property relationships.

Acene werden wegen ihrer einzigartigen elektronischen Eigenschaften, die auf der Topologie ihrer π-Systeme beruhen, seit langem untersucht. Berichte über die bemerkenswerten Halbleitereigenschaften höherer Homologe haben in letzter Zeit zu verstärkten Forschungsaktivitäten geführt. Es wurden neue Verfahren zur Synthese, Funktionalisierung und Reinigung sowie zur Herstellung organoelektronischer Bauteile entwickelt. Durch Untersuchungen an hochreinen Acen-Einkristallen wurden die charakteristischen elektronischen Eigenschaften und Kenngrößen für die Beurteilung von Dünnschichtbauteilen ermittelt. Um die Verarbeitbarkeit in Lösung zu verbessern, wurden neuartige Funktionalisierungsmethoden entwickelt. Die für elektronische Anwendungen erwünschten Eigenschaften nichtfunktionalisierter Acene bleiben bei der Funktionalisierung erhalten. Mit diesen Verfahren wurden kürzlich Derivate höherer Acene als Pentacen, die zuvor kaum zugänglich waren, erhalten, sodass Struktur-Eigenschafts-Beziehungen untersucht werden konnten.