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Reported herein is an electrochemical strategy for N-sulfonylation of azoles with sulfonyl hydrazides, offering efficient access to valuable N-sulfonated azoles. Organic radical species were involved in the process and EPR experiments provided evidence for the formation of intermediates in situ. The electrochemical reaction features metal-free, mild conditions, and a broad substrate scope (>70 examples). The gram-scale synthesis via an electrochemical continuous-flow reaction and late-stage modification of complex compounds is advocated for its practical value. [ABSTRACT FROM AUTHOR]

Reported herein is a photochemical strategy for C(sp3)–H azolation of ethers via a hydrogen-atom transfer and radical-polar crossover process, offering efficient access to valuable N-alkylated azoles under visible-light irradiation. The protocol is metal-free and photocatalyst-free, and exhibits good to excellent yields and broad substrate scope with regard to azoles. EPR experiments provide evidence for the formation of intermediates formed in situ. [ABSTRACT FROM AUTHOR]

Fluorescent carbon dots (CDs) with narrow emissions have been mostly prepared at high temperatures and high pressures, with long reaction times and tedious purification processes, which greatly limits their large-scale production. In contrast, the microwave-assisted solvothermal method can produce CDs simply and rapidly, but often results in wide-emissive CDs with full widths at half maximum (FWHM) larger than 80 nm. In this study, the microwave synthesis of CDs was improved by using ethylene glycol as the solvent and sodium thiosulfate as the oxidant. Consequently, narrow emissive CDs with a FWHM of only 35 nm were obtained from phloroglucinol, and were purified by simple precipitation using a mixed solvent of ethanol and dichloromethane. The structural characterization studies of the obtained CDs reveal that the sulfur element could be doped in the carbon structure with the addition of thiosulfate. It was also demonstrated that the photoluminescence efficiency of the CDs is greatly determined by their carbon core structures and edge groups. In addition, the fluorescence of CDs could be tuned significantly from the blue region to the green region by changing the dispersing solvent. Accordingly, the prepared CDs were successfully applied for the sensing of water content in organic solvents. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSBs) are considered as a new generation of large-scale energy-storage devices. However, LSBs suffer from a lack of desirable cathode materials with excellent specific capacity and cyclic stability. Here, we designed a sulfur-coated nitrogen-doped branched carbon nanofiber (NBCNF@S) hybrid cathode for Li–S batteries, in which the hierarchical structure of the nitrogen-doped branched carbon nanofibers (NBCNFs) with good flexibility and conductivity provides a protective buffer for the volume expansion that occurs during electrochemical processes. The NBCNF@S electrode displayed a reversible specific capacity of 1280 mA h g−1 in the 1st cycle and was able to maintain a stable reversible discharge capacity of 1039 mA h g−1 with the Coulombic efficiency reaching almost 100% for 200 cycles. The electrode was still able to deliver exceptional reversible capacities of 188 and 168 mA h g−1, after 1000 and 2000 cycles, respectively, only decreasing by 0.02%/cycle. The excellent electrochemical performance can be attributed to the confinement of polysulfides, which involves the nitrogen doping effectively preventing the polysulfides from dissolving in the electrolyte during cycling. NBCNF@S synergistically anchors the polysulfides and therefore strongly suppresses the shuttle effect during the charge–discharge process, resulting in less capacity loss and better long-term cycling stability. [ABSTRACT FROM AUTHOR]

There is still great potential to be tapped for polynuclear lanthanide single-molecule magnets (Ln-SMMs) for performance. Toward this goal, the exploration of polynuclear lanthanide clusters (PLnCs) with novel special topologies is critical. Herein, two novel PLnCs, [Dy4(ov6ca)6(CH3OH) (H2O)2]·6CH3OH·CH3CN·H2O (1) and [Dy8(ov5ca)6(a5ca)4(ov)2(μ-OH)6]·6CH3OH (2), have been synthesized, where ov6ca2−, ov5ca2−, a5ca−, ov− represent the ions of 2-[(o-vanillidene)amino]-6-chlorobenzoic acid, 2-[(o-vanillidene)amino]-5-chlorobenzoic acid, 2-amino-5-chlorobenzoic acid and o-vanillin, respectively. Carboxylic decorated o-vanillin Schiff base ligands H2ov6ca and H2ov5ca, were constructed as 1 and 2, respectively, and only differ in the position of a Cl-substituent. However, this tiny difference has induced great variation in the nuclearity and topology between 1 and 2. Cluster 1 features a {Dy4} metallogrid core, where four DyIII ions are bridged by two Ophenol and two carboxylate groups from ov6ca2− ligands but show different coordination geometries. To our knowledge, it is the first {Ln4} cluster with such an asymmetric metallogrid topology. While 2 displays a rare double-layered cage cluster topology, in which a pair of butterfly-shaped {Dy4} units were linked together by four carboxylate groups from ov5ca2− ligands. Magnetic measurements revealed that both 1 and 2 exhibit slow magnetic relaxation behavior, with efficient energy barrier (Ueff) values of 93.06 and 66.92 K, respectively. [ABSTRACT FROM AUTHOR]

Compared with the well-studied cations, the development of methods for anion detection is relatively slow due to the anion characteristics such as a complex geometry, strong hydration and a low charge density. Herein, a colorimetric and ratiometric fluorescent anion sensing platform based on trihexyltetradecylphosphonium chloride ([THTP][Cl]) was developed for the first time. Such nanosensors exhibited a pH response of 5–7 as well as a high selectivity to perchlorate. The selectivity behavior followed the Hofmeister series in which lipophilic anions were more readily co-extracted. To deviate from the Hofmeister series, anion ionophores should be introduced for selective complexation of the target anions. As a proof of concept, the organomercury compounds ETH9033 and ETH9009 were employed as model ionophores. The obtained nitrate- and chloride-selective [THTP][Cl]-based nanosensors demonstrated prominent colorimetric and spectroscopic transformations specifically induced by the anion species. The fluorescence (I675/I600) and absorbance (A650/A500) intensities versus the logarithm values of anion concentrations proved a high selectivity towards the major anion. The excellent performance such as high selectivity, good sensitivity and fast response times enabled the accurate determination of nitrate in mineral water. More importantly, through simply altering the ionophores, a pool of [THTP][Cl]-based anion-selective nano-optodes for extended targets could be achieved. The nanosensor shows great potential for anion determination in the environmental and biomedical fields. [ABSTRACT FROM AUTHOR]

Since the concept of aggregation-induced emission (AIE) was proposed, along with the development of new AIE molecules and broadening of its application field, the exploration of its mechanism has attracted more and more attention. During the past years, various mechanisms have been proposed to reveal this novel phenomenon, including restriction of intramolecular motion (RIM) and restriction of access to the dark state (RADS). However, most of the studies have been focused on the effect of molecular structures and their stacking mode on their AIE behavior, and little effort has been made to reveal the role of the interaction between solvent and AIE aggregates on it. Herein, a series of AIE molecules have been designed and synthesized by introducing the carbonyl group into different aromatic rings, since it possesses a good spin–orbit coupling (SOC) effect and hydrogen bond acceptor, which could allow the molecules to enter the dark state. The solvent effect on their fluorescence properties and excited state electronic structures was investigated by using transient and steady state spectra, X-ray single crystal diffraction spectra and density functional theory (DFT) calculations. It was found that the water molecules not only acted as the poor solvent to induce the significant aggregation and inhibit the nonradiative transition but also as the hydrogen bond donor to induce the RADS process for triggering fluorescence. Moreover, owing to the unique intermolecular hydrogen bond effect on its fluorescence behavior, the 4-(quinolin-8-yl) benzaldehyde (QLB-8) molecule had been applied to the detection of aspartic acid. These results not only clarify the role of hydrogen bonding in AIE properties, but also provide new ideas to further design AIE molecules. [ABSTRACT FROM AUTHOR]

The design and synthesis of non-precious metal composite catalysts with a yolk–shell structure and diverse compositions are challenges in materials science for energy conversion. In this work, we established a facile method to synthesize a series of transition metal oxides with yolk–shell structures (YS structures) by combination of Ostwald ripening and the Kirkendall effect. VO(acac)2 and other transition metal chlorides were chosen deliberately as the interfusion couple for the development of the YS structure. Among all transition binary metal oxides, WVOx has a distinct YS structure which can be preserved well in the following sulfurization. The resultant WS2–V2O3 and WS2–V3S4 yolk–shell spheres were certified to be competitive catalyst candidates for the HER and ORR respectively, due to compositional tuning and the YS structures. The fabricated WS2–V2O3 catalyst exhibits excellent HER electrocatalytic activity with a Tafel slope of 87 mV dec−1 and a small overpotential of 89 mV to reach 10 mA cm−2. The ORR catalyst WS2–V3S4 shows remarkable activity with a positive onset potential of 0.95 V and lower Tafel slope of 51 mV dec−1. [ABSTRACT FROM AUTHOR]

Redox active tetrathiafulvalene (TTF) and its derivatives when used as electrode additives have exhibited improved energy efficiency and sustainability in batteries. However, the structure–property relationship has not been investigated in detail until very recently. In this work, three redox-active TTF compounds were synthesized, and formulated as [Cu(HL)2(bpa)2]n (1), [Cu(bpe)2(H2O)2]n·2n(HL)·nMeOH·nH2O (2), and [Cu(bpp)2(H2O)2]n·2n(HL) (3) (L = dimethylthio-tetrathiafulvalene-bicarboxylate) for this work. The effects of conjugated state and spacer length of the linkers on structural assembly and band gap as well as the interactions of TTF–TTF/TTF-bpy are discussed. Compound 1 is a bpa and HL co-coordinated 1D Cu(II) polymer. Compounds 2 and 3 are 2D Cu(II)-bipyridine (4,4) MOFs incorporating HL (1−) as free anion columns. The photocurrent density of 2 is larger than those of 1 and 3 due to a strong charge transfer from TTF to bpe in compound 2. The supercapacitance performances of these compounds were evaluated by cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) techniques. The results revealed that the 2D MOF structures of 2 and 3 are beneficial for good specific capacitance values (Csp). This work revealed the structure–property relationships of TTF derivatives for use as electrode active materials in energy transfer and storage. [ABSTRACT FROM AUTHOR]

Introducing electronically active organic components into lower dimensional metal halide compounds is an effective strategy to improve the electronic properties of hybrid metal halide materials. We have previously used this strategy to explore hybrid halides with tetrathiafulvalenes (TTFs) and a series of lead iodides and bismuth halides were isolated. The electronic properties were improved notably using this modification. In this work, we expand the study of TTF based main-group metal halides to double metal halides with mixed lead and copper transition metals. Two hybrid TTF–lead–cuprous iodides, formulated as [TTF]5[Pb2Cu2I10]·H2O (1) and [TTF]2[PbCu2I6] (2), and two monometal analogues of [TTF]2[Cu4I6]·H2O (3) and [TTF]2[Ag4I6] (4) were crystallographically characterized. The anion of 1 is a 0D cluster, while that of the others is a 1D chain structure. The anion structures of 1–4 are novel and are reported for the first time. The TTF moieties are stacked to form a 2D framework in 1 and 1D columns in 2–4. We found that the semiconductor properties of the hybrids are related to electron donation from an anion to a cation. The electronic state of the TTF cations is another significant factor that affects the electronic properties of the materials. More notably, this work proved that the conductivity and photoconductivity of the mixed metal iodides are superior to those of the monometal iodides. [ABSTRACT FROM AUTHOR]

Potassium-selective polymer dots (K-Pdots) containing potassium ionophores were for the first time used for photoelectrochemical (PEC) analysis and yielded sensitive and specific detection of potassium ions. The successful PEC analysis using ion-selective Pdots underscored the effectiveness of the strategy deployed and suggested the potential universality of this strategy for the detection of metal ions, which should advance the development of PEC sensors in ion analysis. [ABSTRACT FROM AUTHOR]

Black-TiO2 has become increasingly interesting as a promising photoactive material. Most of the preparations for black-TiO2 involve either high temperature calcination, plasma, lengthy chemical reactions or dealing with dangerous or toxic chemicals. We found, by accident, that Mo–Ti oxo-clusters are efficient catalysts for the hydrogenation of a TiO2 electrode to black-TiO2 at room temperature. A series of Mo–Ti oxo-clusters, [Ti4Mo4O10(OR)14(X-BA)2] (BA = benzoate, X = H (1), F (2), Cl (3), and Br (4)), were prepared and were characterized by crystallography. They have a Mo4Ti4 structure with Mo(V)–Mo(V) metal–metal interactions. The activated hydrogen (H*) generated by electrochemically catalytic water splitting turns the TiO2 electrode to black-TiO2 at room temperature, due to the reduction of Ti(IV) to H+Ti(III). The potentials applied for water reduction must generally be higher than the overpotential at the TiO2 electrode (−1.0 V vs. RHE). In this work, the onset potential of hydrogen evolution significantly decreased to −0.1 V vs. RHE. Using this blackened 1-TiO2 electrode, the effective electrochemical catalytic degradation of a dye was examined in comparison with the degradation using the white TiO2 electrode. This work provides a method for the facile preparation of a black-TiO2 film, and is a step forward in black-TiO2 research. [ABSTRACT FROM AUTHOR]

Upconverting ion-selective nanoparticles that emit light at the near-infrared region are prepared here. The transport of calcium ions induces the deprotonation of the incorporated chromoionophore (P6) through ion exchange resulting in an increase in the emission of UCNPs for the detection of intracellular calcium ions. [ABSTRACT FROM AUTHOR]

Two new tetranuclear lanthanide clusters with the formula [Ln4(L)4(μ2-CH3O)4]·4CH3OH·xC2H5OH (LnIII = Gd (1) and Dy (2), H2L = N′-(4-diethylamino-2-hydroxybenzylidene)-6-(hydroxymethyl)picolinohydrazide, x = 0 for 1 and x = 4 for 2) were assembled by using a polydentate ligand (H2L) reacting with β-diketonate salts (Ln(acac)3·2H2O, LnIII = Gd (1) and Dy (2)). Single-crystal X-ray structures reveal that clusters 1 and 2 are mainly composed of four LnIII ions that are interconnected through eight μ2-O bridging oxygen atoms, and the Ln4 clusters show a 'windmill'-shaped arrangement. The magnetic investigations reveal that cluster 1 displays a cryogenic magnetic refrigeration property with a large magnetic entropy (−ΔSm = 29.0 J kg−1 K−1, ΔH = 7.0 T and T = 2.0 K); meanwhile, alternating current (ac) magnetic susceptibility measurement reveals that 2 exhibits typical SMM behavior with a Ueff/kB of 42.4 K and pre-exponential factor τ0 = 1.2 × 10−6 s. [ABSTRACT FROM AUTHOR]

The poorly conductive organic layers in two-dimensional (2D) perovskites create quantum wells, which hinder the carrier separation and transformation. Therefore, the search for new 2D hybrid lead-halide materials with conductive organic components is crucial to high performance 2D perovskite solar cells. Tetrathiafulvalene (TTF) and its derivatives are well-known building blocks for conductive organic materials. We report here a new compound containing TMT–TTF (tetrakis(methylthio)tetrathiafulvalene) and layered PbI2, formulated as (TMT–TTF)[Pb2.6/3□0.4/3I2]3 (1). Crystal structural analysis shows that compound 1 is a unique TMT–TTF-intercalated 2D hybrid lead iodide with partially oxidized TMT–TTF cations and Pb-vacancy in anion. Its structural characteristics give the compound a narrow band gap and high conductivity. Furthermore, the carrier density and the photoelectric properties are first evaluated for TTF-PbI compounds and the results show that these properties of 1 are superior to those of the previously reported TTF-PbI salt, which is attractive for exploiting new lead-halide materials. [ABSTRACT FROM AUTHOR]

Photoactive nano TiO2 particles with fluorescent properties have attracted great attention because of their potential applications in photodynamic therapy. Herein we report first a simple method to prepare water soluble fluorescent nano titanium oxide particles from titanium-oxo-clusters (TOCs). The nano material was characterized as an aggregate of titanium-oxo-clusters, which can be used directly in aqueous systems for investigations in biomedical fields. [ABSTRACT FROM AUTHOR]

A novel luminescent metallacage was prepared by coordinating silver with benzimidazole tetraphenylethylene. It possesses high stability and strong fluorescence not only in dilute solutions but also in the aggregated state. [ABSTRACT FROM AUTHOR]

The intermolecular interactions and molecular packing form of fluorescent molecules have a huge impact on their optical properties, especially for AIE molecules. As a class of typical AIE molecules, tetraphenylethene (TPE) and its derivatives have prominent optical properties; nevertheless, separation of mixtures of E/Z isomers is a great challenge. Herein, a series of aromatic-substituted TPE derivatives were synthesized and used to separate mixtures of E/Z isomers by common column chromatography with high yields, as confirmed by single crystal analysis, mass spectrometry and NMR spectroscopy. The structure–property relationships of these molecules were systematically investigated by a combination of spectroscopic methods, theoretical calculations and single crystal data analysis. E/Z isomers exhibit many different fluorescent properties, such as AIE and mechanochromic behavior. Moreover, the position of N on the substituted pyridine ring also has an effect on the molecule stack pattern and the fluorescent properties. Collectively, our findings could not only improve the fundamental understanding of the cis/trans isomerization and photophysical properties of TPE derivatives but also provide a good strategy for designing different substituted groups that can produce various functions and have more potential applications. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are a class of crystalline porous materials utilized in various potential applications. However, the development of hollow-structured COFs with defined morphology is important for their further applications, which is rare. Herein, COF with unique hollow shuttle morphology was prepared by a Schiff condensation reaction between 4-(4-aldehyde phenyl)ethylene (TPE) and tetra-(4-aminophenyl) porphyrin (TAP). A detailed mechanistic investigation reveals that an initial self-assembly followed by a similar inside–out Ostwald ripening process is responsible for the hollow capsule formation. The hollow microshuttle-shaped capsule COF is used for studying hemoglobin adsorption, which shows an uptake of 550.82 mg g−1 of hemoglobin. These studies could foreshadow new avenues for the development of porous materials with defined morphologies for the adsorption of biomolecules. [ABSTRACT FROM AUTHOR]

Here, we report the first example of a hydrogel directly assembled from a copper MOP by a facile ultrasonic procedure, and it exhibited excellent antibacterial activity towards Gram-negative and Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

Titanium oxo clusters (TOCs) anchored with photoactive triphenylamine (TPA) dyes are reported for the first time. The TiO2 electrodes modified with the TPA dye pre-anchored TOCs showed excellent photocurrent response properties. [ABSTRACT FROM AUTHOR]

Incorporation of lanthanide ions (Ln) into TiO2 nanomaterials has recently been proved to be an efficient strategy to explore photoelectric active materials. Herein, three lanthanide–titanium oxo-clusters (LnTOCs), formulated as [Ln2Ti6O2(C2O4)4(NO3)2(OiPr)20]·2HOiPr (Ln = La (1), Ce (2) and Eu (3)), are reported. Their structures feature two Ti3O13 subunits and a central La2O14 subunit bridged by four oxalate ions. The cluster core is surrounded by 20 OiPr groups, which easily undergo dealkoxy reactions. TOCs have now been used as photocatalytic materials under ambient conditions, and in most cases they should already not be the original clusters due to their sensitivity to moisture. However, less work on the degradation clusters has been discussed. In this work, the degradation products were carefully characterized and polymeric Ln–TiO–C2O4 materials were obtained. Using such materials, photocurrent response and photocatalytic dye degradation were examined. The improvements in the photocurrent intensity and photocatalytic activity of dye-degradation are attributed to the cooperative effects of lanthanide and oxalate doping in TiO catalysis. [ABSTRACT FROM AUTHOR]

Dehydrogenation of alkanes to generate alkenes is catalyzed by a supramolecular framework of a tetrathiafulvalene derivative under ambient conditions, and a confinement effect of the framework is responsible for the oxidation reaction in the presence of oxygen. [ABSTRACT FROM AUTHOR]

Enzyme-mimicking nanomaterials (nanozymes) have been used to catalyze enzyme-like reactions for various applications. Despite these favorable properties, peroxidase-mimicking nanozymes suffer from the optimum reaction occurring in acidic solutions, which greatly limits their applications in biological systems. Herein, we demonstrate that copper Metal–Organic Polyhedra (Cu-MOP) nanorods exhibit high peroxidase-mimicking activity at a physiological pH value. Cu-MOP nanorods catalyze the generation of strong chemiluminescence signals in the presence of luminol/H2O2 and the oxidation of 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulphonate acid) (ABTS) by H2O2 produces a green color reaction in a neutral pH solution. The Cu-MOP nanorod driven generation of color reactions is applied to develop a H2O2 sensor, and furthermore is implemented to develop a glucose detection platform. [ABSTRACT FROM AUTHOR]

We have reported that dyes with a titanium alkoxide moiety can improve dye-semiconductor surface properties, such as anchoring and molecular distribution. Here, we report three new titanium-alkoxide-dyes (TADs): [Ti2(OiPr)5(Az)(NO2-BA)] (1), [Ti2(OiPr)5(Az)(F-BA)] (2), [Ti2(OiPr)5(Az)(Br-BA)] (3) (H2Az = alizarin dye and HBA = benzoic acid), in which the titanium alkoxide clusters are coordinated with alizarin dye and an auxiliary ligand, namely a benzoic acid substituted with –NO2, –F or –Br. Their photo-absorption was greatly shifted to lower energy, due to the charge transfer from the π-conjugated dye moiety to Ti(iv). The structures of all these compounds could be divided into two functional parts: a conjugated organic photosensitive antenna part and a hydrolyzable anchoring part. Using 1–3 as new sensitive dyes, dye-sensitized TiO2 electrodes were prepared for measurement of the photocurrent response in an I2/I3− solution cell. In comparison with the organic dye-treated TiO2 electrode, considerable improvement in photocurrent density was observed for the TAD-treated TiO2 electrodes. The effect of different substituted auxiliary ligands on the photocurrent conversion was evaluated. Their photocurrent density was in the order NO2 ＞ F ＞ Br, which was in accordance with the electron-withdrawing property of the substituted groups. This work not only demonstrated the advantages of TADs but also showed, for the first time, the effect of electron-withdrawing auxiliary ligands. [ABSTRACT FROM AUTHOR]

Titanium-oxo-clusters (TOCs), [Ti6O4(OiPr)10(Cat)2(BA)2] (1) and [Ti12M2O10(OEt)22(Cat)2(BA)4] (M = Co, Mn, Ni, 2–4; H2Cat = catechol, HBA = benzoic acid) are prepared in one step in an in situ solvothermal synthesis. Cluster structures of 2–4 can be considered as two 1 moieties merged together by two transition metal atoms. Unlike most TOCs with sphere-like structures, clusters 2–4 feature a unique single layered structure. They are not only transition metal doped TOCs but also charge transfer (CT) TOCs, CT from Cat to the TiO cluster core. Photoelectrodes were prepared by dipping the solution of clusters on a porous TiO2 substrate. Photocurrent response properties of the electrodes were studied in comparison with those of the electrodes of non-metal doped 1 and the non-Cat coordinated Ti6 cluster. The results showed that the photocurrent densities of metal doped clusters are higher than that of non-doped clusters and the highest photocurrent density was found for the redox active Co(ii) doped cluster. Charge transfer also plays an effective role in photocurrent conversion under visible light irradiation. [ABSTRACT FROM AUTHOR]

Endohedral lanthanide metallofullerene molecules exhibit various paramagnetic properties. In this study, we present a magnetoreception probe that can detect the magnetic properties of an endohedral metallofullerene via spin-paramagnet interaction between a nitroxide radical and Dy3N@C80. A cycloaddition reaction on the outer cage of Dy3N@C80 was employed to obtain two regioisomers linked with the nitroxide radical; the resultant adduct exhibits site-dependent signal intensity in the ESR spectra. This Dy3N@C80-nitroxide radical adduct has potential applications as a molecular compass with position-sensitive magnetoreception ability. [ABSTRACT FROM AUTHOR]

Supertetrahedral clusters of main-group metal chalcogenides (Tn) have been well-studied for decades. Most of them are polymerized 2D or 3D structures and have been used as porous materials for ion exchange and as ion conductors. Large discrete T5 clusters of main-group metal chalcogenides are attractive in that they might be used as nanocluster materials with uniform size and definite structures. However, until now, discrete T5 clusters have been reported only in the solid state and their dispersed solution has not yet been obtained due to their low solubility in common solvents, thus not to mention their application as nanodots. We prepare a crystal compound with discrete T5 CuInS clusters using a simple and economical way. A solution of the T5 clusters was obtained by a strategy using a medium with strong ionic strength to overcome the strong ionic force in crystals. The discrete T5 clusters in solution is proved by HRTEM and ESI-MS. The nano-T5 CuInS clusters can be easily modified on a TiO2 electrode by a wet process and the clusters show excellent photo-sensitive properties tested by photocurrent and photocatalysis. [ABSTRACT FROM AUTHOR]

Although a lot of titanium oxo-clusters (TOCs) have been synthesized and characterized, research studies on their application properties are still limited. The work described here is not only aimed at the synthesis and crystal structures of the TOCs, but also aimed at exploration of their potential applications in molecule based fluorescence labelling and photocatalysis. Three heterometallic TOC compounds with lanthanide (Ln) elements Sm(iii) (1), Eu(iii) (2) and Gd(iii) (3) are prepared and their cluster structures are characterized as LnTi11 cages. Compound 2 exhibits the characteristic fluorescence of Eu(iii) and the emission intensity can be decreased upon irradiation and recovered by air oxidation, which is attributed to the energy transfer between Eu(iii) and photo-induced Ti(iii) of the oxo-TiO cluster. The fluorescence intensity of 2 can be significantly increased when treated with 1,10-phenanthroline. The catalytic properties of 2 were determined by the degradation of dyes on a paper substrate. Compound 2 has potential applications as a molecule based fluorescent labelling agent and photodegeneration catalyst. [ABSTRACT FROM AUTHOR]

Viologen dication derivatives with a series of alkyl chains are used to assemble charge-transfer salts and films with dimethylthio-tetrathiafulvalene-bicarboxylate which aims to explore the relationship of the alkyl chain length to molecular structures and film morphologies which are important points for the design of molecular materials and manipulation of molecular devices. Four charge-transfer salts generally formulated as [(CnV)(HL)2] [n = 4(1), 8(2), 12(3) and 16(4)] are prepared and 1–3 are characterized by single-crystal X-ray structural analysis. In the short alkyl chain compound, TTF and C4V moieties are regularly arranged and effectively stacked with strong charge-transfer interactions. Lengthening the alkyl chain of the bipyridinium cation reduces the regular and close arrangement of the cations and anions in the crystals, which weakens the charge-transfer interaction while increasing the amphiphilic assembly of the films. Their film morphologies change from crystals to fused crystals, band-like structures and finally to smooth films with the increase of the alkyl chain length. The effects of alkyl chain length on photocurrent intensity are different between the crystal sample-modified electrodes (in the order of 1 ＞ 2 ＞ 3 = 4) and the film-modified electrodes (in the order of 2 ＞ 1 = 3 ＞ 4), because both inter-ion interactions and film-forming properties should be considered for the film electrodes. This is a systematic study of the effect of alkyl chain substitution on film morphologies in terms of crystal structures. [ABSTRACT FROM AUTHOR]

A boronic acid functionalized aza-borondipyrromethene dye (azaBDPBA) was applied to the dual-wavelength detection of hydrogen peroxide with high selectivity, which was loaded into cells to indicate the alteration of intracellular hydrogen peroxide during biological processes. [ABSTRACT FROM AUTHOR]

A series of tetrathiafulvalene (electron donor, D) charge-transfer salts with three methyl bipyridiniums (electron acceptor, A) in the basic formulas MV(HL)2 (1), MeBpe(HL)2 (2) and MeBpa(HL)2 (3) (L = dimethylthio-tetrathiafulvalene-bicarboxylate, MV = methyl viologen, MeBpe = 1,2-bi(4-pyridinium) ethene and MeBpa =1,2-bi(4-pyridinium) ethane) was synthesized and their structures were characterized by X-ray single crystal analysis. The three bipyridiniums allow the exploration of the effect of different conjugated systems on molecular packing and charge-transfer interactions. A type of –DDDD– stacking column with edge-to-edge short D…A…D contacts is found in MV compound 1, while in π-extended MeBpe compound 2, a –DADDAD– type of stacking column with face-to-face short D…D and A…D stacking is formed, which shows the most effective cation–anion interaction. No effective interaction is found for the non-conjugated MeBpa compound 3. The charge-transfer from an anion to a cation measured by UV-vis, CV and ESR is in the order of 2 ＞ 1>3, which is greatly in accordance with the order of the cation's conjugated state and CT interaction. It is known that charge-transfer is a key factor in obtaining photoelectric materials. Photocurrent responses of these compounds are consequently studied and the results agree with the intensity of charge-transfer. This is a systematic study of the effect of different π-conjugated systems on charge-transfer properties in terms of crystal structures. [ABSTRACT FROM AUTHOR]

An organic dye coordinated titanium iso-propoxide compound is designed and synthesized. Taking advantage of the hydrolysis of the titanium alkoxide moiety on the surface of TiO2 electrode, the dye–semiconductor surface properties, including anchoring and dispersivity, are improved, which opens a new perspective to explore dyes for DSSCs. [ABSTRACT FROM AUTHOR]