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Organic semiconductors with high charge carrier mobilities are crucial for flexible electronic applications. Apart from designing new conjugated frameworks, different strategies have been explored to increase charge carrier mobilities. We report a new and simple approach to enhancing the charge carrier mobility of DPP-thieno[3,2-b]thiophene-conjugated polymer by incorporating an ionic additive, tetramethylammonium iodide, without extra treatments into the polymer. The resulting thin films exhibit a very high hole mobility, which is higher by a factor of 24 than that of thin films without the ionic additive under the same conditions. On the basis of spectroscopic grazing incidence wide-angle x-ray scattering and atomic force microscopy studies as well as theoretical calculations, the remarkable enhancement of charge mobility upon addition of tetramethylammonium iodide is attributed primarily to an inhibition of the torsion of the alkyl side chains by the presence of the ionic species, facilitating a more ordered lamellar packing of the alkyl side chains and interchain π-π interactions.

Due to their high electron affinities, chemical and thermal stabilities, π-conjugated molecules with imide/amide frameworks have received considerable attentions as promising candidates for high-performance optoelectronic materials, particularly for organic semiconductors with high carrier mobilities. The purpose of this Research News is to give an overview of recent advances in development of high performance imide/amide based organic semiconductors for field-effect transistors. It covers naphthalene diimide-, perylene diimide- and amide-based conjugated molecules and polymers for organic semiconductors., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

By linking TPE moieties that exhibit aggregation-induced (enhanced) emission to the amphiphilic copolymer 1, fluorescent micelles are prepared and characterized. The polymeric micelles exhibit relatively strong fluorescence which can be tuned by heating and cooling. By combining cascaded enzymatic (oxidation of D-glucose with GOx) and chemical (oxidation of I(-) by H(2) O(2) ) reactions, the fluorescent micelles of copolymer 1 are successfully utilized for the selective detection of D-glucose in aqueous solution. The influences of proteins (e.g., bovine serum albumin) and reductants (e.g., ascorbic acid) on this fluorescence detection of D-glucose are also discussed., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In recent decades, polymer semiconductors, extensively employed as charge transport layers in devices like organic field‐effect transistors (OFETs), have undergone thorough investigation due to their capacity for large‐area solution processing, making them promising for mass production. Research efforts have been twofold: enhancing the charge mobilities of polymer semiconductors and augmenting their mechanical properties to meet the demands of flexible devices. Significant progress has been made in both realms, propelling the practical application of polymer semiconductors in flexible electronics. However, integrating excellent semiconducting and mechanical properties into a single polymer still remains a significant challenge. This review intends to introduce the design strategies and discuss the properties of high‐charge mobility stretchable conjugated polymers. In addition, another key challenge faced in this cutting‐edge field is maintaining stable semiconducting performance during long‐term mechanical deformations. Therefore, this review also discusses the development of healable polymer semiconductors as a promising avenue to improve the lifetime of stretchable device. In conclusion, challenges and outline future research perspectives in this interdisciplinary field are highlighted. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: The development of selenophene‐flanked DPP (SeDPP) based copolymers, especially for the ambipolar ones, lags behind other aromatic group flanked DPP‐based polymers. Herein, we report two new ambipolar SeDPP‐based conjugated polymers. One is the alternating polymer PSeDPPFT with normal SeDPP and 3,4‐difluorothiophene units. The other is PSeFDFT, in which the electron acceptor unit is replaced by a new SeDPP derivative, referred as to half‐fused SeDPP. The more planar structure of half‐fused SeDPP endows the backbone of PSeFDFT with good rigidity and planarity. Both polymers exhibit ambipolar transporting properties in air. The PSeFDFT based field‐effect transistors (FETs) display higher and more balanced ambipolar properties with μhave of 0.27 cm2·V–1·s–1, μeave of 0.18 cm2·V–1·s–1, and μhave/μeave of 1.5 than those of PSeDPPFT (μhave = 0.11 cm2·V–1·s–1, μeave = 0.042 cm2·V–1·s–1, and μh/μe = 2.6). This is attributed to the more planar structure, lower LUMO level, higher HOMO level, and better interchain packing orientations of PSeFDFT by comparing with PSeDPPFT. Therefore, a new molecular design strategy to modulate the hole and electron transporting properties is proposed for conjugated D‐A polymers. [ABSTRACT FROM AUTHOR]

A novel building block, denoted as half‐fused diketopyrrolopyrrole (DPP) (9‐(3‐octadecylhenicosyl)‐8‐(thiophen‐2‐yl)‐7H‐pyrrolo[3,4‐a]thieno[3,2‐g]indolizine‐7,10(9H)‐dione), in which one of the flanking thiophene units is fused to one of the DPP rings via a carbon‐carbon double bond at the N‐position is reported. The half‐fused DPP is successfully utilized as an electron acceptor to prepare the conjugated donor–acceptor polymer PTFDFT, which exhibits ambipolar semiconducting behavior in ambient air. Theoretical calculations and absorption spectral studies show that the backbone of PTFDFT is more planar compared to the reference polymer with conventional DPP units. As a result, PTFDFT shows a narrow bandgap and low lowest unoccupied molecular orbital level. The more planar backbone with fewer side chains favors the dense packing of the polymer chains of PTFDFT with a short π–π stacking distance (3.49 Å). Grazing‐incidence wide‐angle X‐ray scattering data further confirm the predominant edge‐on packing mode of the PTFDFT polymer chains on the substrate. As expected, the PTFDFT thin film shows excellent ambipolar semiconducting properties under ambient conditions, reaching 2.23 and 1.08 cm2 V−1 s−1 for the n‐ and p‐channels, respectively. In addition, complementary‐like inverter with gain value as high as 141 is successfully constructed using the PTFDFT thin film. [ABSTRACT FROM AUTHOR]

Development of high‐performance organic thermoelectric (TE) materials is of vital importance for flexible power generation and solid‐cooling applications. Demonstrated here is the significant enhancement in TE performance of selenium‐substituted diketopyrrolopyrrole (DPP) derivatives. Along with strong intermolecular interactions and high Hall mobilities of 1.0–2.3 cm2 V−1 s−1 in doping‐states for polymers, PDPPSe‐12 exhibits a maximum power factor and ZT of up to 364 μW m−1 K−2 and 0.25, respectively. The performance is more than twice that of the sulfur‐based DPP derivative and represents the highest value for p‐type organic thermoelectric materials based on high‐mobility polymers. These results reveal that selenium substitution can serve as a powerful strategy towards rationally designed thermoelectric polymers with state‐of‐the‐art performances. [ABSTRACT FROM AUTHOR]

Abstract: Ammonia/amine gas sensors have received increasing attention in recent years, due to their applications in monitoring of meat and seafood spoilage and air pollution as well as diagnosis of chronic diseases. Herein, a new conjugated polymer PTTEH is developed, which is composed of thieno[3,4‐b]thiophene units, with very low bandgap. The low bandgap and the existence of radical state endow the polymer thin film with good electrical conductivity. As a result, PTTEH is successfully utilized for construction of a field‐effect transistor (FET) sensor for ammonia and amines at low driving voltages, which are advantageous for practical applications. Moreover, this FET sensor shows good selectivity and high sensitivity (down to 10 ppb) toward ammonia and amines. Accordingly, the real‐time monitoring of meat spoilage is achieved with this FET sensor. These studies will open a new venue to fabricate sensitive, portable, and small size sensors for real‐time monitoring of chemical vapors. [ABSTRACT FROM AUTHOR]

A small band gap conjugated polymer with ternary acceptors of diketopyrrolopyrrole, benzothiadiazole, and naphthalenediimde is presented. Nanowires of this polymer were fabricated to show ambipolar field ‐ effect transistors with hole and electron mobilities of 1.61 and 0.98 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]

Di, D. Zhang et al., wie selensubstituierte Diketopyrrolopyrrolderivate eine hohe thermoelektrische Leistung erreichen können, was einen neuen Weg zu rational entwickelten organischen thermoelektrischen Materialien eröffnet. In ihrem Forschungsartikel auf S. 19124 präsentieren J. Reichert, J. V. Barth, A. C. Papageorgiou et al. komplexe zweidimensionale Netzwerke mit chiralen Poren, die ihren Ursprung in der zunehmenden Deprotonierung eines Adsorbats auf Ag(111) haben. In ihrem Forschungsartikel auf S. 19133 aktivieren E. Bode et al. gezielt Biosynthesegencluster in hfq-Mutanten verschiedener Proteobakterien, um die Isolierung und biologische Testung der dadurch produzierten Naturstoffe zu vereinfachen. [Extracted from the article]

Polyvinyl alcohol/poly(butylene carbonate) (PVA/PBC) core–shell nanofibers are successfully prepared by the coaxial electrospinning technology, in which PVA forms the core and PBC forms the shell. The core–shell microstructure of the fibers is certified by transmission electron microscopy (TEM). FT-IR analysis demonstrates that there is no chemical interaction between PVA and PBC. The as-prepared nanofibers are completely biocompatible and they can be used as a drug loader for doxorubicin (DOX). The DOX loaded nanofibers are quite effective in prohibiting the SKOV3 ovary cells attachment and proliferation, which are potential for chemotherapy of ovary cancer. Besides, the PVA/PBC core–shell nanofibers can be degraded in physiological environment, which is promising in the application of tissue engineering. [ABSTRACT FROM AUTHOR]

• Xylan/PCL core–shell nanofibers were prepared by coaxial electrospinning. • The core–shell fibers possessed good biocompatibility and degradation. • The LEV loaded core–shell nanofibers showed excellent antibacterial properties against E. coli and S. aureus. Xylan/Polycaprolactone (Xylan/PCL) core–shell nanofibers with the flow ratios of 1:1, 1:1.2 and 1:1.4 were successfully prepared by coaxial electrospinning. Xylan was used as the core layer and PCL as the shell layer. The as-prepared fibers were uneven in size and thickness, and bead-on-string structure was formed. The nanofibers can be effectively degraded under acidic or neutral condition. Under the same condition, the degradation rate of the fibers decreased with the increase of PCL's flow rate. Additionally, the resulting Xylan/PCL core–shell nanofibers can be used as carriers for anti-inflammatory drug levofloxacin (LEV). The LEV loaded fibers presented excellent bactericidal performance against E. coli and S. aureus. We anticipated that these biodegradable and biocompatible Xylan/PCL core–shell nanofibers would have potential applications in biomedical fields. [ABSTRACT FROM AUTHOR]

Inthis paper, we report the design, synthesis and semiconductingbehavior of two conjugated D–A polymers P-BPDTTand P-BPDBTwhich entail BPD, a Pechmanndye framework, as electron accepting moieties, and thieno[3,2-b]thiophene and 2,2′-bithiophene as electron donatingmoieties. Their HOMO/LUMO energies and bandgaps were estimated basedon the respective cyclic voltammgrams and absorption spectra of thinfilms. P-BPDTTpossesses lower LUMO level and narrowerbandgap than P-BPDBT. On the basis of the characterizationof the field-effect transistors, a thin film of P-BPDTTexhibits ambipolar semiconducting properties with hole and electronmobilities reaching 1.24 cm2V–1s–1and 0.82 cm2V–1s–1, respectively, after thermal annealing. In comparison,thin film of P-BPDBTonly shows p-typesemiconducting behavior with hole mobility up to 1.37 cm2V–1s–1. AFM and XRD studieswere presented to understand the interchain arrangements on the substratesand the variation of carrier mobilities. [ABSTRACT FROM AUTHOR]

Abstract: New π-conjugated oligomers (1–3) combined of thiophene rings, Cand phenylene rings were synthesized. The monomer (1) was synthesized by Sonogashira cross-coupling reaction. Lithiation and oxidation of the monomer led to the formation of dimer (2) and trimer (3). Optical and electrochemical properties of compounds 1–3 were studied. The oligomers with thioacetyl moieties were synthesized for self-assembly. [Copyright &y& Elsevier]