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The inherent dipole moment and higher polarizability of azulene lead to ambipolar characteristics and good gate controllability of azulene-based single-molecule transistors.

A mechano-sliding strategy for controllable assembly of nanowires was demonstrated by directly transferring chemical vapor deposition grown silicon nanowires to obtain nanoscale electronic devices.

A single-molecule field-effect transistor (FET) is the key building block of future electronic circuits. At the same time, a single-molecule FET is also a unique platform for studying physical mechanisms at the single-molecule level. How to construct single-molecule FETs and how to efficiently control the charge transfer characteristics of the devices are two core issues in the development of single-molecule FETs. In this review, we introduce the research progresses of single-molecule FETs with solid or liquid gates. Strategies to design single-molecule FETs are emphasized, including the design of functional molecules, the construction of gate electrodes and the control of molecule-electrode interface coupling. These single-molecule FETs provide a basis for practical applications and the exploration of physical laws. Specifically, the physical mechanisms of single-molecule FETs, especially those related to interfacial coupling, are explained, such as energy level shift, Coulomb blockade effect, Kondo effect and electron-phonon coupling. The applications of single-molecule FETs are summarized, including the regulation of quantum interference, spin, thermoelectric effect and superconductivity. Finally, the current opportunities and challenges in the field of single-molecule FETs are proposed, aiming to promote the future development of single-molecule electronics.

This paper reports a quasilinear hydrazone-based mononuclear dysprosium(III) compound, namely, {Dy(Hppyh)2(SCN)3}·2MeOH (I), where Hppyh is pyrazine-2-carboxylic acid pyridin-2-ylmethylene-hydrazide. Compound I behaves as a single-ion magnet (SIM) based on the optimal dc field application of 0.7 kOe, showing a complex magnetic relaxation phenomenon with a tunneling relaxation time of 6.1 ± 0.3 × 10−3 s and an effective spin reversal barrier of 22.6 ± 1.1 K for the low- and high-frequency regions, respectively. More importantly, detailed comparative experimental and theoretical investigations reveal that the complex magnetic relaxation was most likely associated with the single DyIII ion behavior as well as the short-range intermolecular magnetic dipolar interactions.

Device fabrication with organic single crystals is an important method for high device performance. High-quality organic semiconductor crystals are usually grown by a lab solution method, by which it is difficult to fabricate crystal arrays on the substrate, let alone achieve industrial production. Therefore, in this work, oriented single crystal arrays have been prepared by epitaxial growth. As an example, 2,7-dioctyl[1]benzothieno[3,2-b]benzothiophene (C8-BTBT) was spin-coated on the surface of a highly oriented melt-drawn isotactic polypropylene (iPP) film on 300 nm SiO2 substrates as an auxiliary dielectric layer, and highly oriented arrays of C8-BTBT single crystals are obtained by epitaxial growth in the solvent vapor annealing (SVA) approach. The devices based on the thus prepared C8-BTBT array have a yield of up to 81%, an average mobility of 2.5 cm2 V−1 s−1, a maximum mobility of 9.3 cm2 V−1 s−1 and an on/off ratio of 107. Hence, our method facilitates the large-scale fabrication of highly oriented single crystal arrays with high quality, which will promote further industrial application.

A noncrystalline Ni–B alloy in the shape of nanotubes has demonstrated its superior catalytic performance for some hydrogenation reactions. Remarkable synergistic effects have been observed in many reactions when bimetallic catalysts were used; however, bimetallic noncrystalline alloy nanotubes are far less investigated. Here, we report a simple acetone-assisted lamellar liquid crystal approach for synthesizing a series of bimetallic Ni–Co–B nanotubes and investigate their catalytic performances. The dilution effect of acetone on liquid crystals was characterized by small-angle X-ray diffraction (SAXRD) and scanning electron microscopy (SEM). The Ni/Co molar ratio of the catalyst was varied to study the composition, porous structure, electronic interaction, and catalytic efficiency. In the liquid-phase hydrogenation of p-chloronitrobenzene, the as-prepared noncrystalline alloy Ni–Co–B nanotubes exhibited higher catalytic activity and increased stability as compared to Ni–B and Co–B alloy nanotubes due to electronic interactions between the nickel and cobalt. The excellent hydrogenation performance of the Ni–Co–B nanotubes was attributed to their high specific surface area and the characteristic confinement effects, compared with Ni–Co–B nanoparticles.

Heteroatom doping is a very important approach to improve the performances of carbon-based electrode materials applied in the energy storage and conversion field. Herein, a strategy based on the design of faradaic redox active sites has been developed to synthesize nitrogen and oxygen co-doped carbon foam with a hierarchical porous structure. By a facile two-step method of incipient impregnation and carbonization, the quinone-amine polymer (PAQ) precursor can be in situ polymerized and carbonized on the surface of a nanosized MgO template to obtain carbon foam after removal of MgO with acetic acid. The obtained carbon foam possesses a high content of heteroatoms (total 12.26 at%) as well as faradaic active sites including nitrogen- and oxygen-containing functional groups, which not only enhance the wettability of the electrode material surface to electrolyte but also impart high pseudo-capacitance to the carbon-based skeleton. In addition, the hierarchical micro–meso–macro porous structure provides a large specific surface area (1215 m2 g−1) and a mediated pathway for electrolyte ion diffusion. Serving as a symmetric supercapacitor electrode material in aqueous electrolyte, the co-doped carbon foam yields excellent performance, delivering a high specific capacitance of 321 F g−1 at 1 A g−1, a superior energy density of 15.91 W h kg−1 at a power density of 0.4 kW kg−1, and excellent long-term stability, retaining 98% of its initial capacitance after 15 000 cycles at 5 A g−1.

The measurements of molecular electronic devices usually suffer from serious noise. Although noise hampers the operation of electric circuits in most cases, current fluctuations in single-molecule junctions are essentially related to their intrinsic quantum effects in the process of electron transport. Noise analysis can reveal and understand these processes from the behavior of current fluctuations. Here, in this study we observe and analyze the faint asymmetric current distribution in single-molecule junctions, in which the asymmetric intensity is highly related to the applied biases. The exploration of high-order moments within bias and temperature dependent measurements, in combination with model Hamiltonian calculations, statistically prove that the asymmetric current distribution originates from the inelastic electron tunneling process. Such results demonstrate a potential noise analysis method based on the fine structures of the current distribution rather than the noise power, which has obvious advantages in the investigation of the inelastic electron tunneling process in single-molecule junctions.

MoO3/C nanocomposites are synthesized by first intercalating alkylamines into layered MoO3 and then in situ carbonization at high temperature. The possible arrangements of alkylamines in the interlayers of MoO3 and the interaction between the inorganic host and the organic guest are discussed. The resulting MoO3/C nanocomposite with a high degree of graphitization exhibits a high specific capacitance of 335 F g−1 at a current density of 1 A g−1 and an excellent rate performance (70% capacitance retained 70% capacitance retained from 1 A g−1 to 10 A g−1). In addition, the obtained nanocomposite can be matched well with expanded graphite to maximize the specific capacitance and also to extend the potential window, giving rise to an increased energy density of the cell. The assembled MoO3/C//expanded graphite asymmetric supercapacitor can be cycled reversibly between 0 and 1.6 V with a specific capacitance of 88 F g−1 at 1 A g−1 and an energy density of 31.3 W h kg−1 at a power density of 838.4 W kg−1. Moreover, this supercapacitor exhibits a good cycling behavior with no more than 13.5% capacitance loss after 5000 cycles at 1 A g−1. The excellent performance is mainly attributed to two aspects. On the one hand, opening up MoO3 layers with conductive carbon can provide more redox sites for Faradaic reaction and promote transportation of electrons. On the other hand, MoO3 and intercalated carbon layers form a sandwich-type hybrid nanostructure, which facilitates the penetration and diffusion of electrolyte ions. This work may pave the way for fabricating active electrode materials for high performance energy storage devices through intercalation and in situ carbonization.

Small molecule solar cells have made great progress in recent years. Herein, we synthesized a novel small molecule donor NDTR with naphtho[1,2-b:5,6-b′]dithiophene (NDT) units as the building blocks. NDTR exhibited complementary absorption for both fullerene acceptor PC71BM and non-fullerene acceptor IDIC. Meanwhile, NDTR possessed a HOMO energy level of −5.23 eV and a LUMO energy level of −3.50 eV, which matched well with these two kinds of acceptors. When mixed with PC71BM, a high power conversion efficiency (PCE) of 7.75% was obtained, while the NDTR:IDIC system presented a PCE of 6.60%. The results indicated that NDTR was an all-round small molecule donor which can work well in both fullerene and non-fullerene systems.

Carbon nanoelectrodes with nanogap are reliable platforms for achieving ultra-small electronic devices. One of the main challenges in fabricating nanogapped carbon electrodes is precise control of the gap size. Herein, we put forward an electroburning approach for controllable fabrication of graphene nanoelectrodes from preprocessed nanoconstriction arrays. The electroburning behavior was investigated in detail, which revealed a dependence on the size of nanoconstriction units. The electroburnt nanoscale electrodes showed the capacity to build molecular devices. The methodology and mechanism presented in this study provide significant guidance for the fabrication of proper graphene and other carbon nanoelectrodes.

The electrostatic field of a dielectric cavity is powerful for modulating many aspects of confined metal clusters. Here we report that the catalytic properties of Ptn clusters confined in X-zeolite cages are strongly tuned by altering the zeolitic field, which is achieved by using different cations (Na+, Cs+, Ca2+ or La3+) to balance the negative framework of the zeolite. Compared with Ptn@LaX, for example, Ptn@CsX shows a surprising ∼5500% enhancement in TOF value for phenol hydrogenation to cyclohexanol. Electrostatic field modulation leads to gradual changes of electronic properties such as the Fermi levels/d-band centers of the Ptn clusters, as revealed by DFT calculations and experimental characterizations. The decreases in Fermi levels of the Ptn clusters benefit the hydrogenation of –CCH groups (phenylacetylene and acetylene) and –NO2 groups (nitrobenzene, o-nitroanisole and o-chloronitrobenzene) but are detrimental for aromatic ring hydrogenation (phenol). These findings are important for the design of high performance catalysts.

Using nanoparticles (NPs) to catalyze multiple chemical reactions in one-pot and to achieve high-yield syntheses of functional molecules/materials is an important direction in NP chemistry, catalysis and applications. In this article, we report a nanocomposite of AgPd NPs anchored on WO2.72 nanorods (NRs) (denoted as AgPd/WO2.72) as a general catalyst for formic acid dehydrogenation and transfer hydrogenation from Ar-NO2 to Ar-NH2 that further reacts with aldehydes to form benzene-fused heterocyclic compounds. The AgPd/WO2.72 catalysis is Ag/Pd dependent and Ag48Pd52 is the most active composition for the multiple chemical reactions. The high activity of AgPd/WO2.72 arises from strong interfacial interaction between AgPd and WO2.72, resulting in AgPd lattice expansion and electron polarization from AgPd to WO2.72. The syntheses proceed in one-pot reactions among formic acid, 2-nitrophenol (or 2-nitroaniline, or 2-nitrothiophenol) and aldehydes in dioxane/water (2/1 v/v) at 80–90 °C, leading to one-pot syntheses of benzoxazoles, benzimidazoles and benzothiazoles that are key ring structures present in functional compounds for pharmaceutical, optical and polymer applications.

A set of identical Co3O4 nanosheets with different oxygen vacancy amounts are rationally designed by varied reduction treatments and comparison of their properties. Remarkably, the oxygen-vacancy-rich Co3O4 nanosheets (OVR-Co3O4 NSs) exhibit excellent electrochemical performance for their potential use as a promising candidate for the next generation of supercapacitors.

The phenomena of charge/energy transfer commonly exist at most heterointerfaces. These processes vary with the change of the electronic structure at the interface, which leads to the diversity of device functionalities. Therefore, interface engineering is a powerful approach to control the charge/energy transfer behavior by modulating the interfacial electronic structure. On the basis of a novel ipsilateral selective electron tunneling (ISET) mechanism, we systematically investigated the charge transfer property at a semiconductor/graphene/photoactive material ternary interface. With acridine orange dye as the photoactive material, photoinduced electrons from the dye can directly tunnel across the TiO2/graphene Schottky barrier into the conductive band of TiO2, while the photoinduced holes were collected by graphene. These results demonstrate the capability of such an ISET-based ternary interface to achieve efficient charge transfer and separation, promising the fabrication of new types of photovoltaic and optoelectronic devices.

The development of sustainable routes for the synthesis of noble metal supported catalysts is of high importance because of their wide applications on a large scale in the catalysis field. Herein we report a facile solvent-free solid-state dispersion route to fabricate highly dispersed ultrafine palladium nanoparticle supported catalysts. In the first step, a noble metal precursor Pd(acac)2 was dispersed spontaneously by treating the physical mixture of Pd(acac)2 and catalyst support hydroxyapatite (HAP) at 120 °C under a flow of N2. Subsequent H2 reduction results in the formation of two kinds of Pd particles. In situ reduction at 120 °C is essential for preparing highly dispersed Pd nanoparticles (∼1.2 nm, a1Pd/HAP-SSD) and cooling-down reduction leads to the formation of larger Pd nanoparticles (∼4 nm, b1Pd/HAP-SSD). The as-prepared a1Pd/HAP-SSD exhibits higher activity for phenol hydrogenation than b1Pd/HAP-SSD and that obtained by a traditional wet impregnation method, due to the highly dispersed ultrafine Pd0 nanoparticles obtained by in situ dispersion/reduction. Compared with conventional wet chemistry-based methods, the synthesis route in this work simplifies the synthesis process, avoids producing large polluted wastes, and enhances the dispersion of noble metals. This may open a new way to prepare highly dispersed/active noble metal supported catalysts and is also potentially of high importance for the green production of noble metal supported catalysts on a large scale in the future.

TiO2@carbon with a nanosheet morphology and core–shell structure was constructed by self-assembly/carbonization of P123, CTAB and exfoliated titanate nanosheets. The obtained composite possesses an ultrathin structure (∼5.5 nm) and exhibits high capacity (549 mA h g−1) and excellent cyclability (385 mA h g−1 after 2000 cycles at 4.6 A g−1) as an anode for Li-ion batteries.

Crystalline mesoporous γ-Fe2O3 with a high surface area was prepared by a novel solvent-free route. This material exhibits a high reversible capacity with superior cycle performance and an exceptional high-rate capability as an anode material for Li-ion batteries.

Anatase-type titania with ultrathin nanosheet morphology and sintering-resistant structure was constructed from monolayer titanate nanosheets isolated by uniform silica nanoparticles. The obtained anatase titania nanosheets possess high accessible surface area, ultrathin thickness (∼0.6 nm), dominant (116) facets exposed, wide bandgap and exhibits excellent photocatalytic activity.

The S-doped mesoporous nanocomposite (S-TNT) of HTiNbO5 nanosheets (NSs) and anatase TiO2 nanoparticles (NPs) with exposed {101} facets has been successfully synthesized by first mixing freeze-dried HTiNbO5 NSs with titanium isopropoxide and then calcination with thiourea in air. The exposed anatase {101} facets can act as a possible reservoir of the photogenerated electrons, yielding a highly reactive surface for the reduction of O2 to O2˙(-). The partial substitution of Ti(4+) by S(6+) in the lattice of TiO2 NPs leads to a charge imbalance in S-TNT and the formation of Ti-O-S bonds. As a result, the formed cationic S-TNT favours adsorption of hydroxide ions (OH(-)(ads)) and thus captures the photo-induced holes to form hydroxyl radicals (˙OH). Moreover, with the formation of Ti-O-S bonds, partial electrons can be transferred from S to O atoms and hence the electron-deficient S atoms might capture photo-induced electrons. The surface-adsorbed SO4(2-) could also act as an efficient electron trapping center to promote the separation of charge carriers. In addition, the Ti(3+) species due to the removal of oxygen atoms during calcination and the associated oxygen vacancy defects on the surface of S-TNT could act as hole and electron scavengers, respectively. Besides, the closely contacted interface is formed between HTiNbO5 NSs and anatase TiO2 NPs due to the common features of TiO6 octahedra in two components, resulting in a nanoscale heterojunction structure to speed up the separation rate of photogenerated charge carriers. The formation of a nano-heterojunction and the incorporation of Ti(3+) and S dopants give rise to the visible and near-infrared light response of S-TNT. The combined effects greatly retard the charge recombination and improve the photocatalytic activity for the degradation of rhodamine B (RhB) and phenol solution under visible light irradiation. The corresponding photocatalytic mechanism was investigated via the active species capture experiments. The present work may provide an insight into the fabrication of delicate composite photocatalysts with excellent performance.

We present an efficient strategy through surface functionalization to build a single silicon nanowire field-effect transistor-based biosensor that is capable of directly detecting protein adsorption/desorption at the single-event level. The step-wise signals in real-time detection of His-tag F1-ATPases demonstrate a promising electrical biosensing approach with single-molecule sensitivity, thus opening up new opportunities for studying single-molecule biophysics in broad biological systems.

Charge injection typically occurring at the electrode/semiconductor interface in organic field-effect transistors (OFETs) is of great importance to the device performance and stability. Therefore, the chemical modulation of electrode/semiconductor heterojunctions provides a promising approach to enhance the performance and even incorporate new functionalities. In this study, we develop an efficient route for constructing optically switchable OFETs featuring a photochromic spirothiopyran (SP) self-assembled monolayer (SAM)-functionalized electrode/semiconductor interface. The photoisomerization of SPs induces a reversible change in the dipole moment of SP-SAMs, which affects the work function of gold electrodes. This change in the electrode work function enables the tuning of the contact resistance between organic semiconductors and metal electrodes. Consequently, the channel conductance of these devices is modulated in a nondestructive manner, thus leading to a new type of cost-effective OFET-based photodetector with high photosensitivity. These results help us to better understand interfacial phenomena and offer novel insights into developing a new generation of multifunctional interfaces and ultrasensitive OFET-based sensors by interface engineering.

Owing to the lattice match, aligned CH3NH3PbI3 perovskite array films composed of CH3NH3PbI3 microribbons with the length at the sub-millimeter scale were fabricated on ST cut quartz which showed a fast photo-response. This method provides a simple and flexible approach to grow oriented crystalline CH3NH3PbI3 arrays at the millimeter scale.

An efficient and simple method, depositing nano iron oxide onto the surface of Pd/SiO2, to construct sintering-resistant Pd nanocatalysts was presented. The introduction of nano iron oxide not only promoted the sintering-resistance of Pd nanoparticles, but also increased the boundary between the Pd and iron oxide. The resultant catalysts exhibited enhanced catalytic activity for aerobic oxidation of benzyl alcohol.

Many metal ions are present in biology and in the human body in trace amounts. Despite numerous efforts, metal sensors with ultrahigh sensitivity (

We report a facile and efficient strategy for preparing flower-like hierarchical mesoporous carbon superstructures (FMCS) through a one-pot hydrothermal reaction of nickel acetate with glucose. In the fabrication process of FMCS, the nickel acetate ingeniously plays multifunctional roles: as inducer of flower-like hierarchical carbon, as catalyst of graphitization, and as pore-forming agent. First, flower-like Ni(OH)2/polysaccharide microspheres were self-assembled via a hydrothermal reaction at 180 °C for 24 h. Second, flower-like mesoporous carbon superstructures were obtained by etching and removing the Ni from the Ni/C precursor carbonized from the Ni(OH)2/polysaccharide microspheres. The obtained flower-like superstructures are composed of two-dimensional mesoporous carbon petal building blocks, with a thickness of 20 nm. Electrochemical data showed that the product FMCS-1 displayed a specific capacitance of 226 F g−1 at 0.5 A g−1, and retained 82% (185 F g−1) at a high current density of 20 A g−1, indicative of outstanding rate capability. Furthermore, the three-dimensional (3D) flower-like hierarchical mesoporous carbon superstructures demonstrated excellent cycling stability, with approximately 100% retention of the initial specific capacitance after 2000 cycles at a current density of 10 A g−1.

To obtain new anode materials with improved lithium storage properties, molybdenum oxynitride (phase X) was developed from a partial nitridation strategy by heating bulk molybdenum trioxide (MoO3) in a NH3 atmosphere. The elemental mapping shows homogeneous distribution of nitrogen and the nominal composition of the material was well characterized by X-ray photoelectron spectroscopy (XPS) in combination with elemental analysis. The material was evaluated as an anode material for lithium ion batteries for the first time. A reversible capacity of about 980 mA h g−1 was achieved at a current density of 50 mA g−1, showing significantly improved capability retention compared to bulk MoO3, which was due to its increased conductivity. Considering the ease of large-scale fabrication, molybdenum oxynitride should be very promising for lithium ion battery applications. The strategy may also be applied to other metal oxides to improve their performances in lithium ion batteries.

We demonstrate the use of P3HT–spiropyran blends as an active layer to achieve reversible photoswitching effects in solution-processed organic field-effect transistors (OFETs). Conformational changes of spiropyrans triggered by light with different wavelengths produce two distinct interaction strengths at organic/organic interfaces that can reversibly modulate the channel conductance of OFETs in a noninvasive manner. This concept of organic–organic interfacial modification offers attractive new prospects for the development of organic electronic devices with desired properties.

A helix with the ternary components of TPPS4, Zn(NO3)2 and C14DMAO is easily obtained in aqueous solution. It retains the characteristic fluorescence of the porphyrin and can be conductive when it bridges on a gold electrode, which provides potential applications in photochemistry and electrical devices.

A catalyst-free sulfonylation reaction of activated alkenes with sulfonyl hydrazides was efficiently developed under mild and environmentally benign conditions, in water without any ligand or additive. The reaction gave a range of structurally diverse mono-substituted ethyl sulfones with excellent yields, in which the by-product was nitrogen.

A novel Au/DNA-catalyzed amidation from alcohols and azides was developed under mild conditions. Taking advantage of the water-soluble reversibility of this catalyst, the transformation could be carried out smoothly in water and the catalyst could be recovered and reused by a simple phase separation. This amidation reaction unitized the hydrogen transfer process and the oxidative coupling process synergistically in an atom economical and environmentally benign synthesis.

Understanding charge transport of single molecules or a small collection of molecules sandwiched between electrodes is of fundamental importance for molecular electronics. This requires the fabrication of reliable devices, which depend on several factors including the testbed architectures used, the molecule number and defect density being tested, and the nature of the molecule-electrode interface. On the basis of significant progresses achieved in both experiments and theory over the past decade, in this tutorial review, we focus on new insights into the influence of the nature of the molecule-electrode interface, the most critical issue hindering the development of reliable devices, on the conducting properties of molecules. We summarize the strategies developed for controlling the interfacial properties and how the coupling strength between the molecules and the electrodes modulates the device properties. These analyses should be valuable for deeply understanding the relationship between the contact interface and the charge transport mechanism, which is of crucial importance for the development of molecular electronics, organic electronics, nanoelectronics, and other interface-related optoelectronic devices.

Au nanoparticles half-encapsulated in nano iron oxide are prepared and loaded on alumina as a support. The donation of electrons from nano iron oxide to Au nanoparticles is detected and both the properties of gold and iron oxide are adjusted by the donation. The properties are different from the bulk iron oxide supported gold catalysts, in which the iron oxide is little influenced by the electronic interaction between the two components. The catalyst shows noticeably promoted activity for the aerobic oxidation of 1-phenylethanol over Au-Al2O3 and Au-bulk FeOx. The enhanced catalytic behavior may result from the cooperative effect between the Au nanoparticles and nano iron oxide.

We report a novel approach to fabricate sandwich-like LiFePO4/graphene hybrid nanosheets as battery materials by means of in situ graphitizing organic interlayers (ISGOI). These sandwich-like LiFePO4/graphene nanosheets demonstrated high rate storage and excellent cycle stability.

The conversion of sugars to chemicals in aqueous-phase is especially important for the utilization of biomass. In current work, zirconium phosphate obtained by hydrothermal methods using organic amines as templates has been examined as a solid catalyst for the dehydration reaction of xylose to furfural in aqueous-phase. The use of dodecylamine and hexadecylamine in the synthesis process results in mesoporous zirconium phosphate with uniform pore width of ∼2 nm and in morphology of nanoaggregates, which is characterized by powder X-ray diffraction, N2 isothermal sorption, NH3 temperature-programmed desorption, FT-IR, and 31P MAS NMR spectroscopy. When used as a catalyst for xylose dehydration to furfural in aqueous-phase, the mesoporous zirconium phosphate presents excellent catalytic performance with high conversions up to 96% and high furfural yields up to 52% in a short time of reaction. Moreover, the catalyst is easily regenerated by thermal treatment in air and shows quite stable activity. The open structure with numerous active sites of the Bronsted/Lewis acid sites is responsible for the high catalytic efficiency of mesoporous zirconium phosphate.

The excimer fluorescence of a bis-pyrene molecule can be reversibly regulated by ultraviolet light, metal ions and visible light in the presence of spiropyran. Based on this result, a new molecular logic circuit is proposed.

The facile synthesis of mesoporous γ-alumina is developed through the partial hydrolysis of Al(NO3)3 aqueous solution with (NH4)2CO3 without organic surfactants. In this synthesis, the stable NH4NO3/Al species (AN/Al) hybrid containing Keggin-Al13 polycations is first prepared, which is the key for the successful formation of mesoporous γ-alumina. XRD, 27Al MAS NMR, TEM, and N2 adsorption and desorption results demonstrate that the as-prepared AN/Al hybrid can be transformed to γ-alumina by treatment at 200 °C and exhibit a wormhole-like mesoporous structure with large surface area up to ∼450 m2 g−1, pore volume of ∼0.3 cm3 g−1 and narrow pore size distribution peaked at ∼3.9 nm after completely removing NH4NO3 at 300 °C. The obtained mesoporous γ-aluminas have high thermal stabilities up to 900 °C and excellent hydrothermal stability. The investigation shows that the synergetic effect of NH4NO3 and Al13 species promotes crystallization of Al species to γ-alumina, which may have a unique mechanism distinct from the mesoporous aluminas reported previously. CO2 adsorption measurements indicate that these mesoporous γ-aluminas have a much higher CO2 adsorption capacity than ordered mesoporous alumina synthesized by the surfactant-templating method and conventional γ-alumina derived from aluminum oxyhydroxides. We believe that this research should be useful for providing new insights into the transformation of transition alumina phases and for synthesizing mesoporous γ-alumina with promising properties for various chemical applications.

We detail a facile fabrication and testing method of functionalizing single-layer graphenes (SLGs) by photoactive TiO2 thin films as test-beds for building efficient multifunctional optoelectronic devices. Interestingly, tuning the photoactivity of TiO2 enables us to realize fast and significant photoswitching effects in TiO2-graphene devices. More importantly, using the hybrid devices as solid-state gas sensors, we have demonstrated a reversible and linear electrical sensitivity towards oxygen gas in the full concentration range (5–100%) at room temperature and ambient pressure, with a calculated minimum detection limit (MDL) of 0.01% oxygen. The unique oxygen sensitivity of the devices is attributed to the synergetic effect of the photoactivity of TiO2 and the environmental ultrasensitivity of SLGs. These results form the basis for new types of future ultrasensitive multifunctional integrated devices for a variety of possible detection and/or sensing applications.

Nanocomposites composed of nanoparticles of iron oxide and aluminium oxide (Fe(2)O(3)-Al(2)O(3)) with a unique structure show a remarkable catalytic performance in Fischer-Tropsch synthesis (FTS), compared with the traditional iron-based catalyst.

A novel mesoporous iron phosphate, possessing a specific surface area of 254 m2 g−1 and average pore diameter of 2.6 nm, is synthesized using a fluoride route.

We demonstrate here for the first time the fabrication of a novel morphology of rutile TiO(2) tapered nanotubes with rectangular cross-sections via a facile hydrothermal method using TiO(2) nanorod as the precursor. A plausible anisotropic corrosion mechanism for the formation of TiO(2) nanotubes is also proposed.

We present a universal lithographic methodology for creating single molecule devices based on single-walled carbon nanotubes as point contacts. These contacts are formed by electron beam lithography and precise oxygen plasma etching. Through robust amide linkages, functional molecular bridges with diamines are covalently wired into carboxylic acid-functionalized nanogaps to afford single molecule devices with desired functionalities.

Ferric molybdate nanotubes prepared based on the Kirkendall effect and solid-state reaction exhibit a unique catalytic property for epoxidation of propene by molecular oxygen.