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A series of aromatic sulfonic acids is synthesized by subjecting arenes and NaHSO4·H2O to high-speed ball milling in the presence of P2O5. It is suggested the aromatic sulfonation occurs via in situ generated H2SO4 to give aromatic sulfonic acids. In some cases, formation of diaryl sulfones was observed.

Although the individual one- and two-dimensional (1D and 2D) carbon nanostructures possess extremely high thermal conductivity, their macroscopic assemblies do not efficiently utilize it due to the larger interfacial contact thermal resistance. To improve the overall performance, the key is the interfacial structure design to provide sufficient pathways for phonon transport with a limited sacrifice or damage to the inherent thermal properties of nanomaterials. Particularly, the resonance of low-frequency lattice vibrations is the most important mechanism for the reduction of the interfacial contact thermal resistance. Based on recent theoretical and experimental studies and observations on interfacial heat transport, we review here a fourfold set of transport problems in this field: (1) low-frequency phonons in 1D and 2D nanostructures for heat transport; (2) the mechanisms of interfacial thermal transport; (3) assembly structure design towards high utilization of the thermal conductivity from individual nanostructures; and (4) recent development of thermal conductivity measurement for individual and assembled nanomaterials.

Deoxygenative chlorination of carbonyl compounds using the HMe2SiCl/FeCl3/EtOAc and HMeSiCl2/FeCl3/EtOAc systems has been systemically investigated. The HMe2SiCl-FeCl3 system showed the advantages of good substrate applicability, mild reaction conditions, simple operation, low cost, and easy availability of raw materials. Also, it provided a simple and efficient synthesis route for carbonyl deoxychlorination via a one-pot method. Using the HMeSiCl2/FeCl3/EtOAc system, the β-methylchalcone derivative could be obtained in good yields in addition to obtaining the chlorinated compound. Finally, two plausible reaction routes were proposed to describe the formation of the chlorinated compound and the β-methylchalcone derivative.

In this paper, one-step preparation of graphene/gold nanoparticle hydrogel film through the hydrothermal method is reported. The hydrogel film could be formed on a glass substrate under hydrothermal conditions, and upon freeze-drying, the aerogel film of 40 μm thickness with satisfying flexibility and strength is obtained. The aerogel composite film is characterized by scanning/transmission electron microscopy, X-ray diffraction, Raman spectroscopy and X-ray photoelectron spectroscopy. Moreover, the aerogel film is directly used as the electrochemical electrode for sensing H2O2, and exhibits good performance with a broad linear range, low detection limit and excellent selectivity. This work provides a route for the fabrication of graphene film material with wide potential in various aspects.

A facile method for oxidation of primary benzylic alcohols to the corresponding aldehydes is reported using NaNO3/P2O5 under high-speed ball-milling conditions. This approach is clean, efficient, and exhibits broad functional group compatibility.

The hydrosilylation reduction of aldehydes and ketones to the corresponding alcohols with polymethylhydrosiloxane (PMHS) as hydrosilanes in the presence of potassium carbonate (K2CO3) has been developed. This Lewis base protocol displays excellent chemoselectivity and can tolerate a number of other reducible functionalities like nitro, sulfone, cyano, alkene, as well as ester. In order to make the mechanism of PMHS based hydrosilylation more clearly, we have isolated the silyl ether intermediates. We find that the PMHS is redistributed into methylsilane (H3SiMe) and a series of siloxanes in the structures of H2SiMeO(SiHMeO)nSiMeH2 (n=0, 1, 2,……), which serve as the active hydrosilanes for the hydrosilylation reaction.

Organic-inorganic halide perovskite solar cell has surged a great wave in photovoltaic field owing to its rapid advances, in which CH₃NH₃PbI₃ as the most conventional active layer has been attracting great attention. Generally, in a CH₃NH₃PbI₃ layer, the unreacted PbI₂ inevitably coexists with the perovskite crystals, especially in the two-step fabrication process. There seems a consensus that appropriate amount of unreacted PbI₂ is beneficial to the overall photovoltaic performance of the device, while as for the disadvantageous aspect of excessively remained PbI₂, it stays at regarding PbI₂ as an insulator. Further investigation and advisable control of the component in perovskite crystal call for a deeper understanding of the remnant PbI₂. In this work, PbI₂-enriched and PbI₂-controlled perovskite films as two extremes are prepared by modulating the crystallinity of the pre-deposited PbI₂ film, and the effects of excessively remained PbI₂ are elucidated on the basis of spectroscopic and optoelectronic studies. The initial charge separation, trap state density and trap state distribution properties are all found to be adverse for the PbI₂-enriched devices, i.e., to deteriorate the photovoltaic performances. Complementarily, the biphasic recombination process is reproduced and the charge carrier recombination dynamics was accelerated owing to the excessively remained PbI₂.

The layer-by-layer assembly of polyethyleneimine and carbon nanotubes is carried out through the electrostatic interactions on colloidal polystyrene templates. The successful spherical growth of polyethyleneimine/carbon nanotube multilayers could be investigated by SEM. The subsequent in situ preparation and deposition of gold nanoparticles on the core–shell composites could yield novel microsphere complexes, which are characterized by SEM, TEM, EDX and XRD. The functional hierarchical microspheres with gold nanoparticles exhibit good catalytic activity in the reaction of reducing 4-nitrophenol to 4-aminophenol.

Based on non-equilibrium Green׳s function method, we investigate the thermoelectric performance for both zigzag (ZSiNRs) and armchair (ASiNRs) silicene nanoribbons with central or edge defects. For perfect silicene nanoribbons (SiNRs), it is shown that with its width increasing, the maximum of ZT values (ZTM) decreases monotonously while the phononic thermal conductance increases linearly. For various types of edges and defects, with increasing defect numbers in longitudinal direction, ZTM increases monotonously while the phononic thermal conductance decreases. Comparing with ZSiNRs, defected ASiNRs possess higher thermoelectric performance due to higher Seebeck coefficient and lower thermal conductance. In particular, about 2.5 times enhancement to ZT values is obtained in ASiNRs with edge defects. Our theoretical simulations indicate that by controlling the type and number of defects, ZT values of SiNRs could be enhanced greatly which suggests their very appealing thermoelectric applications.

MWCNT/octadecylamine hybrids with interesting structures were prepared via a simple ultrasonication and drip-drying method. The morphologies of the hybrids vary from lamellae, balls, to rose-like nanoflowers, depending on the weight ratio of the two components, which could be attributed to the introduction of nanotubes into the long-chained amine with self-organization characteristics. The paper chip sensor based on MWCNT/octadecylamine hybrid shows rapid response, high sensitivity and excellent repeatability to some volatile organic compounds, especially chloroform gas. The proposed sensing mechanism of the hybrid is via the swelling of octadecylamine upon the adsorption of organic gas, thus enlarging the nanotube distance in the MWCNT/octadecylamine hybrid and leading to the conductivity decrease of the paper chip.

Organic–inorganic hybrid perovskite solar cells have achieved great success in recent years. Meanwhile, inverted structured device is an important branch in perovskite photovoltaics owing to its peculiar advantages of low-temperature fabrication process and non-hysteresis behavior. In this kind of device, the electron transport material, as well as the interface between perovskite and electron transport layer (ETL), plays a crucial role in photoelectric conversion process. We report that the utilization of the fullerene derivative blend, PCBM and its dumb-belled dimer, as electron transport material in inverted perovskite solar cells, which could significantly enhance the photovoltaic performances. The morphology of ETL can be regulated by changing the admixing ratio of PCBM and its dimer. Moreover, the steady-state/time-resolved fluorescence and transient photovoltage decay measurements indicate that the optimization of perovskite/ETL interface through an appropriate fullerene blend is beneficial to promote charge separation and suppress charge recombination.

We report the in situ reduction and incorporation of gold nanoparticles into graphene oxide/polyethyleneimine composites with polyethyleneimine acting as the reducing and protecting agent for the gold nanoparticles. The resulting composites with porous structure are obtained through a simple freeze-drying method with the gold nanoparticles uniformly distributed on the graphene oxide sheets. The morphology and composition of the composite are characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction and Raman spectroscopy. The catalytic test indicates that the as-prepared porous gold nanoparticle-embedded composite catalyst could efficiently activate the reduction of 4-nitrophenol to 4-aminophenol. The recycling measurement reveals that the activity of the recovered catalyst decreases a little, mainly due to the restacking of the graphene sheets. Moreover, the porous composites used as packing material in chromatography column and injection syringe exhibit good catalytic performances in the rapid reduction of 4-nitrophenol, implying the potential applications of such porous heterogeneous catalysts in continuous catalytic reaction.

Amorphous InGaZnO (a-IGZO) thin films have been grown on polyethylene terephthalate (PET) substrates using a plasma-assisted pulsed laser deposition (PLD) technique, and a flexible ultraviolet (UV) photodetector (PD) with a simple metal–semiconductor–metal (MSM) structure was prepared on the a-IGZO films. The flexible PD shows relatively good photoresponse characteristics before and after bending, and retains good folding reproducibility after repeated bending up to 500 cycles. More importantly, it shows a fast speed with response and recovery times of 0.8 ms and 2.0 ms, 33.8 ms, which are much faster than that of the reported flexible ultraviolet detectors. The devices reported in this paper provide an optimal way to realize flexible ultraviolet detectors with fast speed.

Applying magnetic nanostructures in high density magnetic data storage is hindered by a lack of suitable substrate. Using density functional theory, we explored the potentiality of graphyne as a template for nanomagnetic bits. Due to the unique porous structure of graphyne, Os atom tightly binds to the graphyne at the hollow site with an in-plane MAE of 18 meV. Through a rigid band model, we introduced the strategy to manipulate the MAE by rearrangement of d-orbitals of Os atom. A large MAE of about 48 meV was obtained for F functionalized Os@graphyne. To obtain the out-of-plane easy axis, we have considered the MAE of several transition-metal combinations. We finally identified Os–Os@graphyne as an excellent candidate for room temperature applications due to the high MAE and the structural stability.

The discovery of intriguing properties related to the Dirac states in graphene has spurred huge interest in exploring its two-dimensional group-IV counterparts, such as silicene, germanene, and stanene. However, these materials have to be obtained via synthesizing on substrates with strong interfacial interactions, which usually destroy their intrinsic $\pi$($p_z$)-orbital Dirac states. Here we report a theoretical study on the existence of Dirac states arising from the $p_{x,y}$ orbitals instead of $p_z$ orbitals in silicene on 4H-SiC(0001), which survive in spite of the strong interfacial interactions. We also show that the exchange field together with the spin-orbital coupling give rise to a detectable band gap of 1.3 meV. Berry curvature calculations demonstrate the nontrivial topological nature of such Dirac states with a Chern number $C = 2$, presenting the potential of realizing quantum anomalous Hall effect for silicene on SiC(0001). Finally, we construct a minimal effective model to capture the low-energy physics of this system. This finding is expected to be also applicable to germanene and stanene, and imply great application potentials in nanoelectronics., Comment: 6 Figures , Accepted by Nano Letters

The layer-by-layer assembly of graphene oxide and diazoresin is carried out via the electrostatic and hydrogen bond interactions on planar substrates and colloidal templates. The successful planar and spherical growth of multilayer could be investigated by UV–vis spectrophotometry and scanning electron microscopy, respectively. Subsequent UV irradiation or heating would convert the ionic bonds and hydrogen bonds to covalent bands, which significantly improves the stability of the multilayer composite against solvent etching. For the cross-linked core–shell composites, the template cores could be removed by dissolution and hollow microspheres are obtained.

Three-dimensional flower-like nanomaterials have wide application due to the large specific surface area. In this letter, the morphology of octadecylamine (ODA) from several common solvents is studied and it is found that from the chloroform and acetone solution, ODA assembles into petal-like structure, which further forms the spherical or flower-like architecture. Furthermore, the composite materials incorporated reduced graphene oxide (rGO) and ODA could well keep the flower-shaped structure of ODA. XRD results show that the introduction of graphene has little influence on the structure of ODA and contact angle test indicates good hydrophobic performance of the rGO/ODA material.

At present, heavy metal pollution has become a major environmental problem, influencing the survival of human and other creatures. Developing heavy metal ion adsorbents, which are environment friendly, of low cost and good performance is one of the effective means to solve heavy metal pollution. Rich low-grade diatomite mineral, as raw material, was modified with calcium carbonate to improve the adsorption properties of diatomite for heavy metal ions. The effects of dosage(m), pH, adsorbing time(t), temperature(T) and concentration of adsorbent(c) on the removal rate of heavy metal ions(Cu2+, Pb2+, Zn2+ and Cd2+) were studied. The results show that under the suitable conditions, T=15 °C, c=1.5 mmol/L, m=10 g/L, t=60 min, in a weak acid environment, the removal effect of the four kinds of metal ions by modified diatomite is the best.

Three new fullerene derivatives with one, two, and three PCBM units, respectively, were synthesized and their photovoltaic properties were investigated. The dumb-belled PCBM derivative showed better photovoltaic performance than PCBM, suggesting that the covalently linked fullerene aggregates are promising acceptor materials in solar cells.

The layer-by-layer (LBL) self-assembly of anionic and cationic multi-walled carbon nanotubes (MWNTs) through electrostatic interaction has been carried out to fabricate all-MWNT multilayer films. The alternate uniform assembly of anionic and cationic MWNTs was investigated by UV–vis spectroscopy. Scanning electron microscopy (SEM) images displayed the growth of the MWNT films.

New amphiphilic [60] fullerene monoadduct TPF and bisadducts BTPF were synthesized and well-characterized. Their aggregation properties in aqueous solution was investigated by UV-vis and TEM methods. In aqueous solution, monoadduct TPF forms irregularly shaped and some rod-like aggregates, whereas bisadducts BTPF gives spherical aggregates with diameters of 50-150 nm. It indicated that the aggregation properties of amphiphilic fullerene derivatives depend on the number of hydrophilic appendage on the C60 cage.

In pH 5.5 phosphate buffer solution, N-n-undecyl-N′-(sodium-p-amino-benzenesulfonate) thiourea (UPT) produced a pair of redox peaks on the bare glassy carbon electrode. At the multi-walled carbon nanotube (MWNT) modified electrode, the electrochemical behavior of UPT enhanced greatly. In the presence of bovine serum albumin (BSA), the peak currents of UPT decreased linearly due to the formation of a super-molecular complex. This method was successfully applied to the determination of BSA in a bovine serum sample.

Calf thymus DNA was electrochemically oxidized at a multi-walled carbon nanotube modified electrode. The potentials for DNA oxidation at pH 7.0 were 0.71 and 0.81 V versus SCE, corresponding to the oxidation of guanine and adenine residues, respectively. The initial 6e-oxidation of adenine, observed in the first scan, resulted a quasi -reversible 2e-redox process of the oxidation product in the following scans.

How to obtain germanene with Dirac electrons preserved is still an open challenge. Here we report a sandwich-dehydrogenation approach, i.e., to fabricate germanene through dehydrogenating germanane in a sandwiched structure. The dehydrogenation can spontaneously occur for the sandwiched structure, which overcomes the problem of amorphization in the heating dehydrogenation approach. The obtained germanene preserve the Dirac electronic properties very well. Moreover, the Fermi velocity of germanene can be efficiently manipulated through controlling the interlayer spacing between germanane and the sandwiching surfaces. Our results indicate a guideline for fabrication of prefect two-dimensional materials., Comment: 23 pages,6 figures

This paper describes the adsorption of electroactive methylene blue (MB) dye onto single-walled carbon nanotubes (SWNTs) to form an electrochemically functional nanostructure and its layered nanocomposite. UV−visible and FT-IR spectroscopy and electrochemistry used for characterization of the MB adsorption onto SWNTs reveal that MB essentially interacts with SWNTs through charge-transfer and hydrophobic interactions, leading to the formation of a MB−SWNT adsorptive nanostructure which exhibits distinct electrochemical properties from those of MB adsorbed onto a glassy carbon (GC) electrode. The interactions between MB and the SWNTs are demonstrated to closely associate with the structural properties of the SWNTs by comparing the electrochemical properties of MB adsorbed onto different substrates, i.e., glassy carbon, SWNTs, and SWNTs intentionally sidewall functionalized with hydroxyl groups (SWNT-OHs). The stable adsorption of water-soluble and positively charged MB molecules onto the SWNTs is further de...

A linear-shaped polystyrene with C60 core was prepared with a novel initiator system, C60Cln (n average value is 20)/Ni(naph)2/P(Ph)3, and Tp was 130 °C. The results of gel-permeation chromatography detected by UV detector and fluorescence spectrum of C60-PSt demonstrated that C60 was chemically bonded to polystyrene. The linear increasing of molecular weights (Mn,GPC) with conversion indicated that this novel initiator system had some characters of living polymerization. A bathochromic shift was found in the UV–vis spectra curves with increasing concentration of C60-PSt in THF solution. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1215–1218, 2005

A series of multiwalled carbon nanotube (MWNT) esters with various alkyl chains of n-butyl, n-hexyl, n-octyl, n-dodecyl, and n-hexadecyl has been synthesized via a concise method, and their solubilities in chloroform were determined by UV−vis absorption spectroscopy. The MWNT ester/polysulfone (PSF) composite films were made by drop casting, and their morphologies was checked by scanning electron microscopic method. The surface and volume conductivities of these films were measured. It was found that while longer alkyl chains can result in better properties such as better solubility in chloroform, better dispersibility in polymer matrix, and better electrical conductivity performance, the n-octyl modified MWNT ester always plays the inflection role, exhibiting the percolative character. While the surface electrical conductivity of the composite films is ohmic, the electrical conductivity along the thickness direction is nonohmic, which may provide the possibility to realize the unique electrical propertie...

[6] Do DD. Adsorption analysis: equilibria and kinetics. London: Imperial College Press; 1998. [7] Gregg SJ, Sing KSW. Adsorption, surface area and porosity. 2nd ed. London: Academic Press; 1982. [8] Alcaniz-Monge J, Cazorla-Amoros D, Linares-Solano A, Yoshida S, Oya A. Carbon 1994;32(7):1277–83. [9] Garrido J, Linares-Solano A, Martin-Martinez JM, Molina-Sabio M, Rodriguez-Reinoso F, Torregrosa R. Langmuir 1987;3: 76.

A general method was developed to incorporate fulleropyrrolidinium into the nanoscale cavities of Nafion membrane through electrostatic interaction. The aggregated sizes and structures of fulleropy...

We report here a method that can be used to easily prepare bulk quantities of solubilized carbon nanotubes. The method is derived from Haddon's method in which we have modified the separation process by using two Soxhlet extractors in the procedure. Both primary and secondary amines could be used as starting materials to solubilize carbon nanotubes in our process, and the solubilized multiwalled carbon nanotubes (MWNTs) were fully characterized. Owing to the large quantity of solubilized MWNTs obtained, several basic properties such as the solubility and the percentage content of tubes in the solubilized samples have been determined and analyzed. Typical solubilized MWNT/polymer composites were also fabricated and their electronic and thermal properties were investigated.

In this paper, the chemical reduction of solubilized multi-walled carbon nanotubes by LiAlH4 was investigated. The amide groups on the nanotubes could be reduced to hydroxyl groups, which was confirmed by FTIR and XPS studies. The Raman spectroscopic investigation showed that the morphology of the nanotubes did not change after the reduction.

Single-walled carbon nanotubes (SWNTs) can react with potassium hydroxide through a simple solid-phase mechanochemical reaction at room temperature to produce single-walled carbon nanotubols (SWNTols) − multiple hydroxyl groups direct-modified SWNTs. The SWNTols are highly soluble in water and can be readily self-assembled into aligned arrays through strong surface hydrogen bond interactions.

Atomic scale imaging using scanning tunneling microscopy has been used to investigate the morphology and structure of high molecular weight polymers attached to carbon nanotubes. A surprising degree of regularity is observed in the attached polymers, suggesting a “nanotube-driven” crystallization process is present. The symmetries of this crystalline state of the polymer are directly determined by the underlying nanotube's chirality. Tunneling spectroscopy further demonstrates that the crystallization of the polymer onto the nanotube results in modifications to the nanotube's electronic structure, as would be expected from a strong polymer−tube interaction. The assembly of nanoscale organics into objects with such perfect order clearly foreshadows the construction of large-scale nanoarchitectures with order over many lengths scales.

The results of characterization had shown that it was [1+2] cycloaddition reaction when [60,70]fullerene reacted with 4,4,5,5-tetramethylidazoline-2-thione (1) and dl-valine by FT-IR, FD-mass, 1H NMR, 13C NMR, UV–Vis spectra. [60]fullerene reacting with 4,4,5,5-tetramethylidazoline-2-thione (1) and other α-aminoacids such as l-leucine and α-aminoisobutyric acid had been also done in order to understand the reaction better, and the possible mechanism was put forward based on the results of characterization. In this reaction, reaction temperature was very important due to the reactivity of different α-aminoacids and the result of the experiment had also shown that the reactivity of dl-valine was more reactive than that of other two α-aminoacids.

The Langmuir and Langmuir–Blodgett (LB) films of a novel crowned [60]fullero-pyrrolidine(CFP) were produced in different conditions. Macroscopic second-harmonic generation of the LB film was investigated by means of AM1 Hamiltonian as well as experiments. The monolayer LB film displayed a periodic fringe pattern. A linear dependence of second-harmonic intensity on the number of layers was observed. The second-order molecular susceptibility χ (2) and hyperpolarizability β were evaluated to be 3.2×10 −8 and 8.3×10 −29 esu .

1,2-(1′,1′,2′,2′-Tetracyanomethanoxymethano)[60]fullerene, a derivative of C60, is a better electron acceptor than the parent C60. The film of PVK doped with 1.6 wt % of this derivative was prepared and characterized. The micromorphology of the film was studied by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). The photoinduced discharge curves and photoconduction spectra of the films were measured. The results showed that PVK doped with the C60 derivative displayed more photoconductivity than that of PVK doped with pure C60 or a mixture of C60 and C70. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 209–213, 1999

1,2-(1′, 1′,2′,2′-tetracyanomethanoxymethano) [60] fullerene has been synthesized. It exhibits stronger ability of accepting electron than pure [60]fullerene. A film of PVK doped with 1.6% by weight of this C60-derivative was prepared and characterized. The measured photoinduced discharge curves and the photoconductivity spectra of the film demonstrate that the photoconductivity of PVK doped with this [60]fullerene derivative is higher than that of PVK doped with pure C60.

A novel salt-derivatized [60]fullerene pyrrolidine nitroxide has been synthesized which readily forms ball-like nanoparticles through self-assembly. Transmission electron microscopy images indicate the formation of spherical particles with a diameter of 80–130 nm, and an LB film of the compound was obtained; the nanoparticles and the LB film were also examined by tapping mode atomic force microscopy.

We report a practical vacuum pressure sensor based on a ZnO nanowire array (NWA). An oriented single-crystal ZnO NWA was synthesized by electrodeposition. The device consists of two ITO glass plates coated with a ZnO NWA. Scanning electron microscopy (SEM) and the x-ray diffraction (XRD) pattern show that the as-grown ZnO NWAs are single-crystal and roughly oriented with the ZnO(002) plane parallel to the substrate. Through measuring the pressure dependent resistance of the sensor at different gas species and temperatures, we discovered that the resistance increases monotonically with vacuum pressure. This demonstrates that a practical vacuum sensor could be fabricated since measurements were carried out with a normal multimeter, with no need for the high sensitivity and costly equipment as routinely required in nanotechnology for extremely weak signals. Measurement at elevated temperature (300 °C) showed that the vacuum sensor is much stabler and more sensitive to O(2) pressure. The principle of the device relates to the adsorbed oxygen species on the large surface area of a ZnO NWA to form a resistive depletion layer at the nanowire (NW) surface.

We have investigated the thermal conductivity of various ice nanotubes (Ice-NTs) using the nonequilibrium molecular dynamics method. The results indicate that Ice-NTs have an unusually high thermal conductivity compared to that of the bulk ices. The thermal conductivity is sensitive to temperature, tube length and diameter, while being insensitive to polarization. We have also studied the confinement effect from single-walled carbon nanotubes (SWCNs). A very remarkable increase in the thermal conductivity is further observed after the Ice-NTs are confined in SWCNs.

One of the critical aspects of nanotechnology is to assemble different nanoscale components into a single system. In such a multicomponent system, the overall functionality depends strongly on the precise location and structural characteristics of each of the constituent components. In this context, we have prepared multicomponent micropatterns of silica particles interposed within the discrete areas of aligned multiwall carbon nanotubes. The patterns were fabricated by dry contact transferring aligned carbon nanotubes onto a tape pre-patterned with a thin layer of gold structure, followed by region-specific adsorption of thiol-modified silica particles onto the gold surface from solution. The dry contact transfer technique has further enabled us to develop micropatterns of aligned single-wall carbon nanotubes with interdispersed non-aligned multiwall carbon nanotubes and microsized carbon fibers sheathed with micropatterned aligned carbon nanotubes.

In terms of lattice dynamics theory, we study the vibrational properties of the oxygen-functionalized single wall carbon nanotubes (O-SWCNs). Due to the C-O and O-O interactions, many degenerate phonon modes are split and even some new phonon modes are obtained, different from the bare SWCNs. A distinct Raman shift is found in both the radial breathing mode and G modes, depending not only on the tube diameter and chirality but also on oxygen coverage and adsorption configurations. With the oxygen coverage increasing, interesting, a nonmonotonic up- and down-shift is observed in G modes, which is contributed to the competition between the bond expansion and contraction, there coexisting in the functionalized carbon nanotube., Comment: 4 pages, 3 figures, 1 table

Multicomponent structures were constructed by DNA-directed self-assembling of multiple carbon nanotubes and gold nanoparticles. The work presented here represents an important advance in constructing many multicomponent nanotube structures for multifunctional material and device applications.

The combination of carbon nanotubes with inorganic nanostructures is believed to be a powerful tool for constructing novel organic-inorganic hybrid architectures with desirable functionalities and applications in many fields ranging from energy storage and conversion, to catalysis, sensing, and medical diagnosis and treatment. Due to the chemically inert graphitic surface of the carbon nanotube, different assembly protocols for building functional carbon nanotube-inorganic hybrids, including covalent and noncovalent routes, have been designed and demonstrated. A better understanding of the chemistry associated with the hybrid assembly holds a key to rational manipulation of the hybrid properties. This critical review discusses nondestructive noncovalent assembly methodologies for constructing diverse carbon nanotube-inorganic hybrid materials and provides the latest advances in this field. Particular focus is given to the noncovalent assembly via functional linking molecules which play pivotal roles in the control of morphology, composition, structure, interface, and thus properties of the hybrid materials.

Layer-by-layer (LBL) multilayer films have been constructed from multiple hydroxyl group directly modified single-walled carbon nanotubes (single-walled carbon nanotubols, SWNTols) and light-sensitive diazoresin (DR). Ultraviolet–visible (UV–vis) absorbance spectra confirm that the alternate assemblies of SWNTols and DR result in uniform film growth. Fourier transformed infrared (FT-IR) spectra of the films show that the main driving force for DR/SWNTol assembly is attributed to hydrogen bond attractions rather than electrostatic interactions. Upon UV irradiation, the hydrogen bonds of the multilayer films transform into covalent bonds, which significantly improves the stability of the DR/SWNTol multilayer films towards etching by polar solvent. Atomic force and scanning electron microscopies (AFM and SEM) indicate high structural homogeneity of the assembled composite films.

We have synthesized three new 1,3-diazaazulene derivatives, namely, 2-(4′-N,N-dimethylaminophenyl)-6-nitro-1,3-diazaazulene (18, DMAPNA), 2-(4′-aminophenyl)-6-nitro-1,3-diazaazulene (19, APNA) and 2-[4′-N-(2-hydroxyethyl)aminophenyl]-6-nitro-1,3-diazaazulene (20, HEAPNA), each of them contains an amino substitute as the electron donor (D), 2-phenyl-1,3-diazaazulene as the π-conjugated bridge and a nitro as the electron acceptor (A). Our theoretical results have predicted that these D–π–A type chromophores possess low ground-state dipole moment (μg) and large first-order hyperpolarizability (β), which may facilitate a low degree of aggregation for the chromophores dispersed in a polymeric matrix as well as a large nonlinear optical (NLO) response. The expected NLO performance has been confirmed by the experimental β and μg values, e.g., for 18, 407.8 × 10−30 esu and 4.7 D, respectively. The origins of large β and low μg are explained in terms of a two-state quantum model. The DMAPNA (18)-doped and poled polymethylmethacrylate film exhibits a large second harmonic generation (SHG) coefficient of d33 = 10.9 pm V−1 with excellent thermal stability (above 70% of the maximal SHG coefficient remains at ∼100 °C).

The optical-limiting properties of several water-soluble phthalocyanine derivatives in aqueous solution were measured at 532 nm with 10 ns pulses. The excited state absorption cross-section σex of the derivatives were determined with the Z-scan technique. The results showed that the phthalocyanine derivatives are materials for reverse saturable absorption. It was noted that the optical limiting performance of the phthalocyanine derivatives in aqueous solutions can be controlled through the addition of alkalis. These phthalocyanine derivatives possess good solubility in water and optical limiting controllability, which give rise to their use for practical applications.