In this account, the synthesis and applications of pyrene-fused acenes, as well as pyrene-fused azaacenes, have been carefully reviewed. Moreover, the synthetic methods involving two key synthons (different lengths of dienes and ynes) have been included. Furthermore, the “clean reaction” strategy has been introduced for the preparation of pyrene-fused acenes with a single terminal-pyrene unit from tetracene to octacene, as well as for the synthesis of pyrene-fused octatwistacenes and nonatwistacenes with double terminal-pyrene units. Similarly, the synthons and the synthetic methods for pyrene-fused azaacenes have also been summarized. The applications of pyrene-fused acenes and pyrene-fused azaacenes have been included.

In this research, we successfully synthesized and fully characterized the new compound 5,8,13,16,21,24-hex-(triisopropylsilyl)ethynyl)-6,23-dihydro-6,7,14,15,22,23-hexaza-trianthrylene (HHATA, brown color in a mixed solvent of CH₂Cl₂/CH₃CN 1:1, v/v, weakly blue fluorescent), which can be easily oxidized to 5,8,13,16,21,24-hex-(triisopropylsilyl)ethynyl)-6,7,14,15,22,23-hexazatrianthrylene (HATA) (yellow color in CH₂Cl₂/CH₃CN 1:1, v/v), red fluorescent) by Cu²⁺ ions. This reaction only proceeds efficiently in the presence of Cu²⁺ ions when compared with other common metal ions such as Fe³⁺, Co²⁺, Mn²⁺, Hg²⁺, Ni²⁺, Pb²⁺, Ag⁺, Mg²⁺, Ca²⁺, K⁺, Na⁺, and Li⁺. Our result suggests that this reaction can be developed as an effective method for the detection of Cu²⁺ ions.

Two new quaternary thioarsenates(III), SrAg₄As₂S₆⋅2 H₂O (1) and BaAgAsS₃ (2), have been prepared through a hydrazine-hydrothermal method at low temperature. Compound 1 possesses a two-dimensional (2D) layer network, while compound 2 features a one-dimensional (1D) column structure. The detailed structure analysis indicates that Sr²⁺ and Ba²⁺ cations have different directing effects on the structures of thioarsenates(III). Both experimental and theoretical studies demonstrate that compounds 1 and 2 are narrow-gap semiconductors. Our success in synthesizing these two quaternary thioarsenates(III) proves that the hydrazine-hydrothermal technique is a powerful yet facile synthetic method for exploring new complex chalcogenides with diverse crystal structures and interesting physical properties.

To meet the ever-increasing requirements for the next generation of sustainable and versatile energy-related devices, conjugated polymers, which have potential advantages over small molecules and inorganic materials, are among the most promising types of green candidates. The properties of conjugated polymers can be tuned through modification of the structure and incorporation of different functional moieties. In addition, superior performances can be achieved as a result of the advantages of nanostructures, such as their large surface areas and the shortened pathways for charge transfer. Therefore, nanostructured conjugated polymers with different properties can be obtained to be applied in different energy-related organic devices. This review focuses on the application and performance of the recently reported nanostructured conjugated polymers for high-performance devices, including rechargeable lithium batteries, microbial fuel cells (MFCs), thermoelectric generators, and photocatalytic systems. The design strategies, reaction mechanisms, advantages, and limitations of nanostructured conjugated polymers are further discussed in each section. Finally, possible routes to improve the performances of the current systems are also included in the conclusion.

Two organic small molecule memory materials, TPA-2BIPs and TPA-3BIPs, containing triphenylamine (TPA) as a donor and 4,11-bis((triisopropylsilyl)ethynyl)-1 H-imidazo[4,5-b]phenazine (BIP) units as acceptors have been synthesized and characterized. Sandwich-structure memory devices based on these two molecules have been fabricated and the as-fabricated devices displayed similar switching behavior but different ON/OFF ratios. The analysis of AFM images indicates that increasing the numbers of acceptors changes the stacking of molecules in the solid state, which results in different morphology and microstructures in films. Although the switching behavior is not significantly different with increasing acceptor moieties, more acceptor groups do help to enhance the stacking of the molecules in the solid state to generate more consistent switching performance.

A novel electron-deficient heteroacene 15H-pyrazino[2″,3″:3′,4′]pyrrolo[1′,2′:1,2]imidazo[4,5-b]phenazin-15-one (1) has been successfully synthesized and characterized. Compound 1 can selectively recognize CN⁻ and F⁻ over other 10 anions including BF₄⁻, PF₆⁻, Cl⁻, SO₄²⁻, NO₃⁻, I⁻, H₂PO₄⁻, ClO₄⁻, Ac⁻, and Br⁻ in CHCl₃/DMF mixed solvents with dual responses, including absorption signals and fluorescent “turn-off” effects. CN⁻ and F⁻ can be distinguished by the completely quenched fluorescence (for CN⁻) and partially reduced fluorescence (for F⁻). Especially, compound 1 exhibits higher sensitivity to CN⁻ than F⁻ with the response concentration as low as 5.0 × 10⁻⁶ mol/L. Moreover, compound 1 shows very interesting solvatochromism effect, and the CHCl₃ solution of compound 1 is sensitive to triethylamine, and its emission could change from green to red upon the addition of triethylamine, which is attributed to the n–π intermolecular charge-transfer interaction.

A new tetraazatetracene derivative, 2,3-[4,4′-bis(N,N-diphenylamino)benzyl]-5,12-bis[(triisopropylsilyl)ethynyl]-1,4,6,11-tetraazatetracene (TPAs-BTTT), displays rewritable multilevel memory behavior, which is probably induced by multielectron intramolecular charge transfer (CT).

The front cover artwork is provided by the group of Qichun Zhang at Nanyang Technology University (Singapore). The image shows the extracellular electron transfer between a graphene–carbon nanotube hybrid biofilm anode and­ Shewanella oneidensis­ cells. Read the full text of the Communication at10.1002/celc.201402458.

Mit Blick darauf, dass Tenside die Form und Größe von Mikro- und Nanopartikeln steuern können, sollten sie auch in der Lage sein, das Wachstum von makroskopischen Kristallen zu dirigieren. Dieser Kurzaufsatz fasst jüngste Entwicklungen bei der Verwendung von Tensiden zur Herstellung neuer kristalliner anorganischer Materialien aus dem Bereich der Chalkogenide, Metall-organischen Gerüstverbindungen und Zeolithanaloga zusammen. Die Rolle der Tenside in den verschiedenen Reaktionssystemen wird diskutiert.

Increasing the length of N-heteroacenes or their analogues is highly desirable because such materials could have great potential applications in organic electronics. In this report, the large π-conjugated N-heteroquinone 6,10,17,21-tetra-((triisopropylsilyl)ethynyl)-5,7,9,11,16,18,20,22-octaazanonacene-8,19-dione (OANQ) has been synthesized and characterized. The as-prepared OANQ shows high stability under ambient conditions and has a particularly low LUMO level, which leads to it being a promising candidate for air-stable n-type field-effect transistors (FETs). In fact, FET devices based on OANQ single crystals have been fabricated and an electron mobility of up to 0.2 cm² V⁻¹ s⁻¹ under ambient conditions is reported. More importantly, no obvious degradation was observed even after one month. Theoretical calculations based on the single crystal are consistent with the measured mobility.

Inserting polymers into a crystalline inorganic matrix to understand the structure, position, and the structure–property relationships of the resulting composites is important for designing new inorganic-organic materials and tuning their properties. Single crystals of polymer-chalcogenide composites were successfully prepared by trapping polyethyleneglycol within a selenidostannate matrix under surfactant-thermal conditions. This work might provide a new strategy for preparing novel crystalline polymer-inorganic composites through encapsulating polymer chains within inorganic matrices.

Increasing the length of N-heteroacenes or their analogues is highly desirable because such materials could have great potential applications in organic electronics. In this report, the large π-conjugated N-heteroquinone 6,10,17,21-tetra-((triisopropylsilyl)ethynyl)-5,7,9,11,16,18,20,22-octaazanonacene-8,19-dione (OANQ) has been synthesized and characterized. The as-prepared OANQ shows high stability under ambient conditions and has a particularly low LUMO level, which leads to it being a promising candidate for air-stable n-type field-effect transistors (FETs). In fact, FET devices based on OANQ single crystals have been fabricated and an electron mobility of up to 0.2 cm² V⁻¹ s⁻¹ under ambient conditions is reported. More importantly, no obvious degradation was observed even after one month. Theoretical calculations based on the single crystal are consistent with the measured mobility.

Given that surfactants can control the shape and size of micro-/nanoparticles, they should be able to direct the growth of bulk crystals. This Minireview summarizes recent developments in the application of surfactants for the preparation of new crystalline inorganic materials, including chalcogenides, metal–organic frameworks, and zeolite analogues. The roles of surfactants in different reaction systems are discussed.

Inserting polymers into a crystalline inorganic matrix to understand the structure, position, and the structure–property relationships of the resulting composites is important for designing new inorganic-organic materials and tuning their properties. Single crystals of polymer-chalcogenide composites were successfully prepared by trapping polyethyleneglycol within a selenidostannate matrix under surfactant-thermal conditions. This work might provide a new strategy for preparing novel crystalline polymer-inorganic composites through encapsulating polymer chains within inorganic matrices.

An N-heteropentacene, 1,2,5,6-tetra(5-hexylthiophene-2-yl)-hexaazapentacene (4HP), was synthesized through one-step cyclocondensation reaction. The binding behavior of 4HP toward various cations (Ca²⁺, Cd²⁺, Co²⁺, Cr²⁺, Cu²⁺ Fe³⁺, Hg²⁺, K⁺, Li⁺, Mg²⁺, Mn²⁺, Na⁺, Ni²⁺, Zn²⁺, and Pb²) was investigated by UV/vis and fluorescence spectroscopy. 4HP demonstrated a selective and sensitive response towards Cu²⁺ ion, and the detection limit reached 1.2 μM in N,N-dimethylformamide solution.

Although azapentacenes have been widely demonstrated as promising candidates for n-type organic semiconductor devices, the exploration of larger azaacenes is still a challenge. In particular, theoretical studies on the electronic structures of larger azaacenes and the influence of N substitution on the ground states are still rare. Herein, we reported our investigation on the electronic ground-state characters of larger azaacenes through density functional theory (DFT) calculations. Our results indicated that larger azaacenes (fused aromatic rings larger than 6) would show open-shell singlet biradical characters and the introduction of more N atoms into the backbone of large acenes could favor their closed-shell ground states. Interestingly, azahexacenes with three or more N atoms (compounds N64–N68) and azaheptacenes (compound N74) with fourteen N atoms displayed closed-shell singlet ground states compared with the open-shell singlet diradical ground states for larger acenes. Our theoretical studies may guide the design and synthesis of larger azaacenes, which are the promising n-type organic semiconducting materials.

N-substituted heteroacenes have been widely used as electroactive layers in organic electronic devices, and only a few of them have been investigated in organic resistive memory devices. Here, a novel N-substituted heteroacene 2-(4′-(diphenylamino)phenyl)-4,11-bis((triisopropylsilyl)ethynyl)-1H-imidazo[4,5-b]phenazine (DBIP) has been designed, synthesized, and characterized. Sandwich-structure memory devices based on DBIP have been fabricated and the devices show non-volatile and stable memory character with good endurance performance.

A new chemodosimeter based on pyridinium-fused pyridinone iodide (PI) has been obtained through a “clean reaction” method. This compound can detect CN⁻ in aqueous solution with a high selectivity and rapid response. The detection of CN⁻ occurs through the nucleophilic attack of CN⁻ on the CN bond, which induces the destruction of the π-conjugation on the pyridinium ring. Support of this detection mechanism was obtained by ¹H NMR titration, HR-MS, and DFT calculations. Upon the addition of 10 equivalents CN⁻ to a solution of PI in THF/H₂O (1:1, v/v), a 57-fold enhancement in fluorescence intensity was observed at the maximum emission wavelength of 457 nm. Meanwhile, the maximum absorption wavelength was also blue-shifted from 447 nm to 355 nm. Other common anions such as BF₄⁻, PF₆⁻, F⁻, Cl⁻, Br⁻, I⁻, H₂PO₄⁻, ClO₄⁻, CH₃COO⁻, NO₂⁻, N₃⁻, and SCN⁻ had little effect on the detection of CN⁻. The response time of PI for CN⁻ was less than 5 seconds. The detection limit was calculated to be 5.4×10⁻⁸ M, which is lower than the maximum permission concentration in drinking water (1.9 μM) set by the World Health Organization (WHO).

A new two-dimensional (2D) oxosulfide, (N₂H₄)₂Mn₃Sb₄S₈(μ₃-OH)₂ (1), has been successfully synthesized under surfactant–thermal conditions with hexadecyltributylphosphonium bromide as the surfactant. Compound 1 has a layered structure and contains a novel [Mn₃(μ₃-OH)₂]_n chain along the b-axis. The photocatalytic activity for compound 1 has been demonstrated under visible-light irradiation and continuous H₂ evolution was observed. Our results indicate that surfactant–thermal synthesis could be a promising method for growing novel crystalline oxochalcogenides with interesting structures and properties.

A concise method for preparing five tetraazadioxaacene derivatives through condensation reactions between 2,3,7,8-tetraaminodibenzo-1,4-dioxin tetrahydrochloride and commercially available diketones has been developed. The as-prepared compounds have interesting photophysical and electrochemical properties. Cyclic voltammetry measurements demonstrate that compounds 4 and 5 have less negative reduction potentials, which is inconsistent with the results of DFT calculations, and both might be promising for use as active elements in organic electronics.

Two novel larger azaacenes with six or ten N atoms in their backbones, benzannelated 9,11,13,22,24,26-hexazatetrabenzo[a,c,l,n]heptacene (HATBH, 1) and benzannelated 9,26-dihydro-9,11,13,22,24,26-hexaza-tetrapyrido[3,2-a: 2′,3′-c: 3′′,2′′-l: 2′′′,3′′′-n]heptacene (DHATPH, 2), have been successfully synthesized in two steps. The theoretical band gaps estimated through DFT calculations for HATBH (1) and DHATPH (2) are 1.949 eV and 2.278 eV, which are close to the experimentally obtained optical band gaps (2.14 eV and 2.39 eV). Interestingly, HATBH (1) can act as efficient anion sensor for F⁻ and H₂PO₄⁻, while DHATPH (2) selectively responds to F⁻ among the ten different anions used (F⁻, Cl⁻, Br⁻, I⁻, PF₆⁻, HSO₄⁻, NO₃⁻, BF₄⁻, AcO⁻, and H₂PO₄⁻). Our synthetic strategy could offer a promising and easy way to obtain even larger azaacenes.

A novel compound, 5,7,14,16-tetraphenyl-8:9,12:13-bisbenzo-hexatwistacene (TBH), has been successfully synthesized through a retro-Diels–Alder reaction. Single-crystal structure analysis indicated that TBH has a twisted configuration with a torsion angle of 27.34°. The HOMO–LUMO gap of TBH calculated from the difference between the half-wave redox potentials (E_1/2^ox=+0.40 eV and E_1/2^red=−1.78 eV) is 2.18 eV, which is in good agreement with the band gap (2.19 eV) derived from the UV/Vis absorption data. In addition, organic light-emitting devices using TBH as emitter have been fabricated. The results revealed that TBH is a promising red light-emitting candidate for applications in organic light-emitting diodes.

Recent studies have demonstrated that single-walled carbon nanotube (SWCNT) films can be doped by a nitric/sulfuric acid treatment to significantly improve its conductivity. However, the sheet resistance is still too high for many applications. Here we report on a simple treatment using a piranha mixture that could further enhance SWCNT film conductivity. The high redox potentials of hydrogen peroxides combined with the acidity of sulfuric acid enabled strong p-doping of the carbon nanotube films. Absorption peak suppression and a G-band shift provided proof of strong p-doping of the SWCNT films.

We report the synthesis and characterization of a novel, stable and blue heteroacene, 2-methyl-1,4,6,7,8,9-hexaphenylbenz(g)isoquinolin-3(2H)-one (BIQ 3). BIQ 3, with its relatively small π framework, has an absorption λ_max at 620 nm, which is larger than that of pentacene (λ_max=582 nm), but BIQ 3 is more stable. The solutions of BIQ 3 are observed without any noticeable photobleaching on the order of days. In the solid state, it is very stable at ambient conditions and can be stored indefinitely. Owing to its pyridone end unit, BIQ 3 can display different resonance structures in different solvents (aprotic and protic) or Lewis acids to give different colors. The attractive stability exhibited by BIQ 3 is very desirable in organic semiconductor devices. Herein, we investigated a simple heterojunction photovoltaic device based on BIQ 3 as an electron donor and [6,6]-phenyl-C₆₁ butyric methyl ester as an electron acceptor. Our results show that this type of heteroacene could be a good candidate as a charge-transport material in organic semiconductor devices.

An asymmetric twistacene, 1′,4′-diphenyl-naphtho-(2′.3′:1.2)-pyrene-6′-nitro-7′-methyl carboxylate (tetracene 2), was synthesized by using benzyne-trapping chemistry. Its structure, determined by X-ray crystallography, confirmed that this material has a twisted topology with torsion angles as high as 23.8(3)°. Organic light-emitting devices using tetracene 2 as either charge-transporting materials or emitters have been fabricated. The results indicate that this material has bipolar transporting behavior in these devices.