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Considerable efforts have been devoted to achieving stable acene derivatives for electronic applications; however, the instability is still a major issue for such derivatives. To achieve higher stability with minimum structural change, CC units in the acenes were replaced with isoelectronic BN units to produce a novel BN‐embedded tetrabenzopentacene (BNTBP). BNTBP, with a planar structure, is highly stable to air, moisture, light, and heat. Compared with its carbon analogue tetrabenzopentacene (TBP), BN embedment lowered the highest occupied molecular orbital (HOMO) energy level of BNTBP, changed the orbital distribution, and decreased the HOMO orbital coefficients at the central carbon atoms, which stabilize BNTBP molecules upon exposure to oxygen and sunlight. The single‐crystal microribbons of BNTBP exhibited good performance in field‐effect transistors (FETs). The high stability and good mobility of BNTBP indicates that BN incorporation is an effective approach to afford stable large‐sized acenes with desired properties. [ABSTRACT FROM AUTHOR]

Polycyclic conjugated hydrocarbons containing antiaromatic four‐membered cyclobutadienoids (CDB) are of great fundamental and technical interest. However, their challenging synthesis has hampered the exploration and understanding of such systems. Reported herein is a modular and efficient synthesis of novel CBD‐containing acene analogues, dinaphthobenzo[1,2:4,5]dicyclobutadiene (DNBDCs), with orthogonally tunable electronic properties and molecular packing. The design also features strong antiaromaticity of the CBD units, as revealed by nucleus‐independent chemical shift and anisotropy of the induced current density calculations, as well as X‐ray crystallography. Tuning the size of silyl substituents resulted in the most favorable "brick‐layer" packing for triisobutylsilyl‐DNBDC and a charge mobility of up to 0.52 cm2 V−1 s−1 in field‐effect transistors. Introducing strong antiaromaticity: Reported here is a modular and efficient synthesis of a series of dinaphthobenzo[1,2:4,5]dicyclobutadienes with strong antiaromaticity, orthogonally tunable electronics and molecular packing, and high charge mobility. These features allow the application of the structures in organic electronics. CANAL=catalytic arene‐(oxa)norbornene annulation. [ABSTRACT FROM AUTHOR]

p- or n-Dopants have played significant roles in the improvement of organic electronic devices through the controllable doping of organic semiconductors. However, there has been little study of air-stable n-dopants under ambient conditions with strong doping capability due to the low electron affinities of organic semiconductors. Herein, a 1,4-dihydropyridine-based derivative is designed and facilely synthesized as an efficient n-dopant. The doping process is systematically investigated by UV-vis-NIR spectroscopy in solution and ultraviolet photoelectron spectroscopy in the solid state. Excellent conductivities are obtained for a variety of doped n-type semiconductors via a simple solution process without further treatment, suggesting a broad class of 1,4-dihydropyridine derivatives could be used as n-dopants in future organic electronic devices. [ABSTRACT FROM AUTHOR]

Benzopyrazinoisoindigo, a pigment reported 40 years ago, should be a good candidate for n-type semiconductors if the reported structure is correct. Reinvestigation of this molecule revealed that it is actually (4 H,4′ H)-benzopyrazinoisoindigo, which could be considered as the reduced form of benzopyrazinoisoindigo, and hence, it is a good candidate for p-type semiconductors. The route toward the synthesis of this molecule was optimized, and a mechanism was accordingly proposed. A field-effect transistor based on this material showed a hole mobility up to 2.5 × 10-2 cm2 V-1 s-1. [ABSTRACT FROM AUTHOR]

One dimensional (1D) Ca 2 Co 2 O 5 with hierarchical structure has been fabricated by electrospinning successfully for the first time. The formation process of hierarchical structure Ca 2 Co 2 O 5 are investigated by powder X-ray diffraction and scanning electron microscopy. High Seebeck coefficient (maximum value of 191 μV K −1 ) and power factor (maximum value of 1.85×10 −4 W m 1 K −2 at 963 K) could be realized by fabricating 1D hierarchical structure assembled by nanoplates. This work provides a step forward in the design of other materials with similar layered building blocks in the crystal structure. [ABSTRACT FROM AUTHOR]

Boron–nitrogen units were incorporated into thiophene‐fused polycyclic aromatic compounds. Organic field‐effect transistors based on these azaborine compounds were fabricated, demonstrating a novel engineering concept of organic semiconductors and providing opportunities of a broad class of BN‐containing compounds for application in future organic electronic devices (see picture; μFET=hole mobility). [ABSTRACT FROM AUTHOR]

An effective method was developed to prepare triphenyleno[1,2,3,4-ghi]perylenediimide derivatives, via ICl-induced annulation, dehalogenation, followed by photocyclization. A perylenediimide (PDI) dimer featuring a terphenyl bisethynylene linker was thereby transformed into a benzo[k]tetraphene fused with two benzoperylenediimides. These PDI derivatives exhibited electron mobility up to 0.079 cm2 V−1 s−1 in solution-processed thin film transistors. [ABSTRACT FROM AUTHOR]

Review: [30 refs. [ABSTRACT FROM AUTHOR]

The title nanowires are synthesized from an ethylene glycol solution of AgNO3, Na2TeO3, and NaOH, which is microwave-heated rapidly to 190 °C and maintained at this temperature for 15 min. [ABSTRACT FROM AUTHOR]

Ten isoindigo-based polymers were synthesized, and theirphotophysicaland electrochemical properties and device performances were systematicallyinvestigated. The HOMO levels of the polymers were tuned by introducingdifferent donor units, yet all polymers exhibited p-type semiconducting properties. The hole mobilities of these polymerswith centrosymmetric donor units exceeded 0.3 cm2V–1s–1, and the maximum reached 1.06cm2V–1s–1. Becauseof their low-lying HOMO levels, these copolymers also showed goodstability upon moisture. AFM and GIXD analyses revealed that polymerswith different symmetry and backbone curvature were distinct in lamellarpacking and crystallinity. DFT calculations were employed to helpus propose the possible packing model. Based on these results, wepropose a design strategy, called “molecular docking”,to understand the interpolymer π–π stacking. Wealso found that polymer symmetry and backbone curvature affect interchain “moleculardocking” of isoindigo-based polymers in film, ultimately leadingto different device performance. Finally, our design strategy maybeapplicable to other reported systems, thus representing a new conceptto design conjugated polymers for field-effect transistors. [ABSTRACT FROM AUTHOR]

Abstract: In this work, PbS nanocubes and nanorods were fabricated via a facile hydrothermal method without using any template and surfactant. The structure and morphology of as-prepared PbS nanocrystals were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and high-resolution transmission electron microscopy (HRTEM). It was found that the anisotropic structure of PbS nanorods were composed of numerous assembled nanocubes, which had an uniform morphology with the mean diameters of about 100–200nm and lengths of 0.5–7μm. Furthermore, a possible growth mechanism was proposed to explain the formation of the nanorods on the basis of the time-dependent experimental results. [Copyright &y& Elsevier]

A reinvestigation of the title pigment reveals that it is actually alkylated (4H,4′H)-benzopyrazinoisoindigo (Ia-c), which could be considered as the reduced form of benzopyrazinoisoindigo, and hence, it is a good candidate for p-type semiconductors. [ABSTRACT FROM AUTHOR]

A large fused pyrene derivative (IV) is easily prepared by fusion at the non-K-region of pyrene for the first time. [ABSTRACT FROM AUTHOR]