Volume 82, Issue 11

In light of the global financial crisis, innovation becomes more critical, especially for industry. The crisis thus heightens the relevance and importance of the 5th International Symposium on Novel Materials and Their Synthesis (NMS-V) and the 19th International Symposium on Fine Chemistry and Functional Polymers (FCFP-XIX) (www.nms-iupac.org). Since the initial conference in 2005 [1], this is the 5th serial symposium of NMS together with FCFP, which was organized by Fudan University and the University of Wollongong in Shanghai, 18-22 October 2009. The National Natural Science Foundation of China, the Science and Technology Commission of Shanghai Municipality, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Shanghai Society of Chemistry and Chemical Industry, and the National Basic Research Program of China (2007CB209700) provided valuable financial support. The symposium was carried out under the auspices of IUPAC. The main objectives of the symposium were to present state-of-the-art preparation of novel materials, and to discuss their performance and application potentials. The wide scope of the symposium provided a multidisciplinary high-level academic exchange chance on new ideas and latest findings for the scientific community. At the same time, the forum gave young scientists the opportunity to know some international authorities in their specialized areas and to develop professionally as quickly as possible. The symposium also opened other doors for the participants to learn more about Fudan University, Shanghai, and China. The symposium was attended by 420 participants from 33 countries and areas. The scientific program comprised 7 plenary lectures, 235 invited lectures, 107 posters, and 1 NMS Nobel Public Lecture. Detailed, active, and lively discussions were covered by the following six themes: - innovative catalytic and other synthetic methods, including chiral and asymmetrical synthesis - innovative polymer materials, including supramolecular (supermolecular, dynamers), conducting, semiconducting, and biobased polymers, their properties, and characteristics - innovative energy systems, including fuel cells, solar cells, lithium batteries, and supercapacitors, and their key materials (PS-III: International) - innovative nanomaterials and their characterization and application - new ceramic materials, such as superconductors, electronic, diaelectronic, ferroelectric, piezoelectric, optoelectric, and magnetic materials - other novel materials, including drugs, perfumes, agricultural chemicals, electrical materials, photo sensitive materials, displaying materials, and fine ceramics and their preparation A selection of 17 papers based on specially invited presentations to NMS-5/FCFP-19 is published in this issue to demonstrate the quality and scope of the themes of this symposium. During the symposium, the role and contributions of this high-level academic platform to novel materials and their synthesis are well realized by the participants, sponsors, and exhibitors. In addition, the organization committee established the "Distinguished Award 2009 for Novel Materials and their Synthesis", and Prof. Makoto Shimizu from Japan and Dr. Klaus Kurz from Germany received the award for their excellent work. Three winners for the IUPAC Poster Prize were also awarded. The advisory board and the organization committee have approved holding this symposium every October. The committees also discussed the IUPAC Prof. Jiang Novel Materials Youth Prize, which will be formally awarded at the 2011 symposium with the support of IUPAC and Prof. Yingyan Jiang, the honorary chairman of this serial symposium. Yuping Wu and Guoxiu Wang Conference Editors 1. Y. P. Wu. Pure Appl. Chem. 78 , iii (2006).

We have developed efficient synthetic routes to heterocyclic ring systems using transition metals (palladium, iron, and silver). Recent applications of this chemistry to the total synthesis of biologically active alkaloids include carbazole alkaloids (pityriazole, euchrestifoline, the antiostatins), crispine A, pentabromo- and pentachloropseudilin. The two latter alkaloids represent a novel class of myosin ATPase inhibitors that led to the discovery of a new allosteric binding site of the protein.

An unsymmetrically substituted triphenylene, with two adjacent chloroethoxyethyl lateral flexible chains, was synthesized and characterized. Although this compound showed no mesomorphic behavior, it formed a donor–acceptor charge-transfer complex with 2,4,7-trinitrofluorenone (TNF). The resulting 1:1 complex has been investigated using UV–vis and IR spectroscopy, optical microscopy, thermal analysis, and X-ray diffraction. A columnar mesophase with hexagonal symmetry was found. More interestingly, this charge-transfer complex can be easily aligned on a glass surface in a homeotropic orientation, which is stable at room temperature (RT) and over a wide temperature range.

Gold nanoclusters (NCs) stabilized by the poly( N -vinyl-2-pyrrolidone) hydrophilic polymer (Au:PVP) behave not only as aerobic oxidation catalyst but also formal Lewis acid catalyst, which promotes the intramolecular heterocyclization of γ-hydroxyalkenes and γ-aminoalkenes.

The kinetic Monte Carlo (MC) model of nanowhisker (NW) growth is suggested. Two variants of growth are possible in the model—molecular beam epitaxy (MBE) and chemical vapor deposition (CVD). The effect of deposition conditions and growth regimes on the whisker morphology was examined within the framework of the vapor–liquid–solid (VLS) mechanism. A range of model growth conditions corresponding to NW and nanotube formation was determined. The suggested MC model was used for analyses of the morphology of the catalyst–whisker interface and for examination of Si–Ge whisker growth.

One-dimensional (1D) nanostructures have received prime attention due to their high potential in understanding fundamental physical concepts and constructing nanoscale electronic devices. ZnS and CdS, the well-known direct and wide bandgap semiconductors, have recently attracted significant research interest due to their special properties and applications in sensing, optoelectronics, piezoelectronics, and lasing. This article reviews the most recent activities in ZnS and CdS nanostructures, with an emphasis on the authors’ own results, and on 1D ZnS and CdS nanostructures, especially those synthesized using vapor deposition techniques. The review begins with a survey of ZnS and CdS nanostructures, and then is primarily focused on their 1D nanostructures, syntheses, characterizations, formation mechanisms, and optical and field-emission (FE) properties. Additionally, developments of Zn x Cd 1– x S composite nanostructures, including nanocombs and zigzag nanowires, are also discussed. Finally, we conclude this review with the perspectives and outlook on the future developments in this field.

This article presents a comprehensive review of the current research addressing the surface effects on physical properties and potential applications of nanostructured ZnO. Studies illustrating the transport, photoluminescence (PL), and photoconductivity properties of ZnO with ultrahigh surface-to-volume (S/V) ratio are reviewed first. Secondly, we examine recent studies of the applications of nanostructured ZnO employing the surface effect on gas/chemical sensing, relying on a change of conductivity via electron trapping and detrapping process at the surfaces of nanostructures. Finally, we comprehensively review the photovoltaic (PV) application of ZnO nanostructures. The ultrahigh S/V ratios of nanostructured devices suggest that studies on the synthesis and PV properties of various nanostructured ZnO for dye-sensitized solar cells (DSSCs) offer great potential for high efficiency and low-cost solar cell solutions. After surveying the current literature on the surface effects on nano-structured ZnO, we conclude this review with personal perspectives on a few surface-related issues that remain to be addressed before nanostructured ZnO devices can reach their ultimate potential as a new class of industrial applications.

One-dimensional (1D) Bi-based nanostructures are promising thermoelectric materials and, furthermore, are very interesting systems for studying physical and chemical properties in the nanoscale, owing to their anisotropic character. The main challenges in this area are to control the diameter, orientation, and alloy composition with precision, and thereby to gain ready access to junction and superlattice structures. Here, we review our recent contributions toward advances in pulsed electrodeposition-based routes to fabricate Bi-based nanostructures. As a main theme, porous anodic alumina membranes (AAMs) have been employed as effective templates to fabricate Bi elementary, alloy, junction, and superlattice structures, and unique properties are demonstrated.

Since the discovery of carbon nanotubes (CNTs) in 1991, widespread research has been carried out to understand their useful physical and electronic properties and also to explore their use in devices. CNTs have many unique properties such as tunable electrical resistance, mechanical robustness, and high thermal conductivity, which when combined with other inorganic materials such as phosphors or superconductors could lead to hetero-structures with diverse functionality. We have been able to obtain mass production of such materials wherein CNTs form core-shell heterostructures with metals, semiconductors, insulators, and even metal-semiconductor heterojunctions. The emerging strategy employs a high-temperature chemical vapor deposition (CVD) technique and high heating rates. Interestingly, due to their high temperature stability, CNTs can act as a nanoreactor for production of exotic materials inside it. In this article, we take ZnS-filled CNTs as an example to explain our synthesis strategy. We explore the optical behavior of these complex materials, analyzing both their luminescence and degradation upon exposure to an electron beam. In addition, the mechanical response of filled CNTs has been evaluated individually inside a transmission electron microscope fitted with an atomic force microscopy–transmission electron microscopy (AFM–TEM) sample holder. Many applications can be envisioned for these nanostructures ranging from nanothermometers to photo-protective storage and delivery devices.

The high surface area and controlled pore size of mesoporous materials made them efficient support for the dispersion of nanoparticles. In particular, highly dispersed Pt-loaded mesoporous materials are interesting systems for nanotechnology and catalysis. The structural, textural, and surface properties of a mesoporous support play a critical role in nano-particle synthesis. This article presents the development of dispersion of nanoparticles on mesoporous supported materials such as MCM-41, SBA-15, KIT-6, and CMK-3 and their properties. Future research trends toward new approaches to designing Pt nanoparticles for electrochemical applications are proposed.

An excitation energy transfer in a bulk heterojunction based on freestanding silicon nanocrystals (Si-NCs) and conjugated polymers {poly(3-hexylthiophene) (P3HT), poly[2-methoxy-5-(2-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV)} is demonstrated. The electrochemical etching process is employed for fabrication of freestanding and polymer soluble Si-NCs. Formation of a bulk heterojunction is confirmed by a difference in a work function of both polymers and an ionization potential of the NCs. An annealing step significantly influences the polymer chain conformation and electronic interaction between the polymer and the NC, which improves the exciton energy migration. The presence of the Si-NCs in polymers suppresses the relative intensity of vibronic peaks, resulting in a red-shift of the blend photoluminescence (PL) spectra. This phenomenon is attributed to a temperature-dependent migration process of singlet exciton and Dexter excitation energy transfer from the polymer to the NC. Compared to MEH-PPV polymer, a lamella-type stacking structure of the P3HT and an abridged PL spectra overlap with NCs decreases an excitation energy transfer rate. At the same time, an improvement in photocurrent generation is recorded when Si-NCs are embedded in P3HT polymer. After Dexter-like excitonic energy transfer, the PL emission of both blends is controlled through a quantum confinement effect and electron-hole recombination in Si-NCs.

Long-length nanofibers are able to form porous networks with high surface-area-to-volume ratios, and decrease diffusion lengths. While there are numerous techniques to create nanostructures, electrospinning is the only technique that allows fabrication of nanofibers at long-length scales. These uniquely shaped fibers are applied to several energy-related devices. This review is an in-depth summary of the uses of electrospun fibers in dye-sensitized solar cells (DSSCs), batteries, capacitors, fuel cells, and hydrogen storage devices. Developments in electrospinning technologies to create novel fiber morphologies are also discussed.

The effects of hydrochloric acid and sodium hydroxide as leachants on the lithium-insertion properties of pyrolytic carbons prepared from rice husk are presented. All the disordered carbonaceous products had interlayer spacings ( d 002 ) of more than 3.7 Å, with values decreasing with an increase in the concentration of the leachant. The values of the H/C ratio and the R -parameter, the reciprocal of which is a measure of the number of non-parallel single layers of carbon, also diminished with an increase in the concentration of NaOH. An increase in the alkali concentration was found to improve the porosity of the carbons, as evidenced by the Brunauer–Emmett–Teller (BET) surface area data. An interaction of these factors determines the observed capacities of the carbon products. The highest insertion and deinsertion capacities were observed with the carbon obtained from rice husk treated with 0.3 M NaOH, the values being 819 and 463 mAh/g, respectively.

A kind of nanocomposite polymer based on poly(acrylonitrile-methyl methacrylate) [P(AN-MMA)] copolymer was prepared by in situ polymerization of monomers on the surface of TiO 2 nanoparticles, which come from the hydrolysis of Ti(OC 4 H 9 ) 4 . Analysis of Fourier transform-infrared (FT-IR) spectra indicated that the acrylonitrile (AN) monomers copolymerized with the methyl methacrylate (MMA) monomers by breaking their own double bonds. The dependence of ionic conductivity on temperature for the resulting nanocomposite polymer electrolyte (NCPE) followed the Arrhenius equation. The ionic conductivity of the NCPE was 1.12 × 10 –3 S cm –1 at room temperature when the nanocomposite polymer membrane (NPM) contained 10.8 % of mass fraction of TiO 2 nanoparticles.

We report the fabrication of and investigations into the dielectric and thermal properties of epoxy/boron nitride nanotube (BNNT) composites. It was found that BNNT fillers can effectively adjust the dielectric constant of epoxy. Moreover, the thermal conductivity of epoxy was improved by up to 69 % with 5 wt % BNNTs. Our studies indicate that BNNTs are promising nanofillers for polymers, to obtain and control an adjustable dielectric property and improved thermal conductivity.

One-dimensional (1D) inorganic semiconductor nanostructures have witnessed an explosion of interest over the last decade because of advances in their controlled synthesis and unique property and potential applications. A wide range of gases, chemicals, biomedical nanosensors, and photodetectors have been assembled using 1D inorganic semiconductor nanostructures. The high-performance characteristics of these nanosensors are particularly attributable to the inorganic semiconducting nanostructure high surface-to-volume ratio (SVR) and its rationally designed surface. In this review, we provide a brief summary of the state-of-the-art research activities in the field of 1D inorganic semiconductor nanostructure-based nanosensors. Some perspectives and the outlook for future developments in this area are presented.

The design principles of fluorescence-based siderophore sensor molecules for detection of heavy transition-metal (HTM) ions are first reviewed. As an example, fluorescein-desferrioxamine (FlDFO), a highly efficient fluorophore molecule combining a specific Fe ion receptor and a fluorescence-sensitive signalling site has been designed, synthesized, and used for dosing with Fe ions. Its response test shows its high selectivity and sensitivity to Fe III ions and its potential for nanobiosensor design. This work clearly identified that among two FlDFO positional isomers differing by the attachment of DFO at the 5- or 6-position of the bottom benzene ring of Fl, the fluorescence of 6-FlDFO is insensitive to the complexation with Fe ions. This is independent of the linkage used between Fl and DFO. Only 5-FlDFO could be a highly potential sensor molecule since it has been revealed that in a free state without complexation with Fe ions, this fluoroionophore sensor molecule gave a maximum fluorescent signal. With successive Fe ion complexing, the fluorescence of 5-FlDFO decreased very sensitively and proportionally with ion concentration. The response speed has been evaluated as a function of Fe ion concentration. Responses to other metal ions present in the solution, such as Cu 2+ , Ca 2+ , Ni 2+ , and Al 3+ , and the effect of pH value on the efficiency of the sensor molecules have also been investigated.

Highly sensitive electrochemical electrodes for glucose detection were developed by using Au nanoclusters (NCs) to modify nitrogen-doped diamond-like carbon thin films (DLC:N/Au). The DLC:N/Au electrodes were prepared with a filtered cathodic vacuum arc process followed by electrodeposition and characterized by X-ray photoelectron spectroscopy, Raman spectroscopy, and scanning electron microscopy. The size of the Au NCs covered by Au oxide ranged between 10 and 70 nm with a density of 10 8 –10 9 clusters per cm 2 . Glucose oxidation at the DLC:N/Au electrodes started from about –0.5 V due to the high catalytic activities of the Au NCs in NaOH solutions, and the catalytic ability of the electrodes depended on the amount of Au NCs deposited on the electrode surfaces. A linear detection range of glucose with the DLC:N/Au electrodes was identified from about 0.25 to 30 mM (covering blood glucose levels in diabetic patients) with a detection limit of 60 μM. The experimental results showed that the non-enzymatic glucose sensors based on the DLC:N/Au electrodes had high sensitivity and good reproducibility and stability.