http://www.hindawi.comThe latest articles from Hindawi Publishing Corporation© 2012, Hindawi Publishing Corporation. All rights reserved.http://www.hindawi.com/journals/jnt/2012/328565/A simple method employing ionic liquid functionalization is developed to achieve the uniform decoration of reduced graphene oxide sheets with gold nanoparticles. The synthesis of ionic liquid modified graphene oxide is accomplished by covalently binding 1-(3-Aminopropyl) imidazole with GO sheets. The formation mechanism of Au nanoparticles on RGO sheets is proposed to load AuCl4- onto the surface of GO sheets through anion exchange; then reduce AuCl4- to Au NPs and at the same time reduce GO sheets to RGO sheets via a one-step process. The presence of Au NPs is well identified by SEM, TEM, and XPS. As a concept, the RGO-supported Au NPs is applied to surface-enhanced Raman spectroscopy.Huanping Yang, Weiwei Zhou, Bo Yu, Yingying Wang, Chunxiao Cong, and Ting YuCopyright © 2012 Huanping Yang et al. All rights reserved.http://www.hindawi.com/journals/jnt/2012/483976/This paper discusses the fabrication and characterization of electrospun nanofiber mats made up of poly(4-methyl-1-pentene) polymer. The polymer was electrospun in different weight concentrations. The mats were characterized by their basis weight, fiber diameter distribution, contact angles, contact angle hysteresis, and air permeability. All of the electrospun nonwoven fiber mats had water contact angles greater than 150 degrees making them superhydrophobic. The permeabilities of the mats were empirically fitted to the mat basis weight by a linear relation. The experimentally measured air permeabilities were significantly larger than the permeabilities predicted by the Kuwabara model for fibrous media.Sarfaraz U. Patel, Gabriel M. Manzo, Shagufta U. Patel, Prashant S. Kulkarni, and George G. ChaseCopyright © 2012 Sarfaraz U. Patel et al. All rights reserved.http://www.hindawi.com/journals/jnt/2012/167128/Low-cost solar cells have been the subject of intensive research activities for over half century ago. More recently, dye-sensitized solar cells (DSSCs) emerged as a new class of low-cost solar cells that can be easily prepared. Natural-dye-sensitized solar cells (NDSSCs) are shown to be excellent examples of mimicking photosynthesis. The NDSSC acts as a green energy generator in which dyes molecules adsorbed to nanocrystalline layer of wide bandgap semiconductor material harvest photons. In this paper we investigate the structural, optical, electrical, and photovoltaic characterization of two types of natural dyes, namely, the Bahraini Henna and the Yemeni Henna, extracted using the Soxhlet extractor. Solar cells from both materials were prepared and characterized. It was found that the levels of open-circuit voltage and short-circuit current are concentration dependent. Further suggestions to improve the efficiency of NDSSC are discussed.Khalil Ebrahim Jasim, Shawqi Al-Dallal, and Awatif M. HassanCopyright © 2012 Khalil Ebrahim Jasim et al. All rights reserved.http://www.hindawi.com/journals/jnt/2012/371487/Biomolecular detections performed on carbon nanotube field-effect transistors (CNT-FETs) frequently use reactive pyrenes as an anchor to tether bioactive ligands to the hydrophobic nanotubes. In this paper, we explore the possibility of directly using bioactive aromatic compounds themselves as CNT-FET ligands. This would be an efficient way to functionalize CNT-FETs since many aromatic compounds bind avidly to nanotubes, and it would also ensure that ligand-binding molecules would be brought in close proximity to the nanotubes. Using a model system consisting of pyrene, phenanthrene, naphthalene, or phenyl boronic acids immobilized on CNT-FET wafers, we show that all are able to bind glycated human serum albumin (gHSA), which is an important diabetes marker. Pyrene boronic acid proved to bind CNTs with the greatest apparent affinity as measured by gHSA impedance. Interestingly, gHSA CNT-FET signal intensity, which is proportional to amount of protein bound, remained essentially unchanged for all the boronic acids tested.Steingrimur Stefansson, Lára A. Stefansson, Suk-won Chung, Kevin Ko, Hena H. Kwon, and Saeyoung Nate AhnCopyright © 2012 Steingrimur Stefansson et al. All rights reserved.http://www.hindawi.com/journals/jnt/2012/195106/HDA-capped ZnO nanoparticles were prepared by solvothermal method using solvents of different polarities. A number of parameters were kept constant such as temperature, pressure, time, and pH while solvents were varied, that is, water, ethanol, and acetone. The TEM was used for the structural properties and morphologies such as spheres, mixture of rods, and spheres and stars were obtained in ethanol, acetone, and water, respectively, in a given reaction time of 15 minutes. Both ethanol and acetone gave rods with high aspect ratio primarily because of the lengths of the rods. Water and ethanol have the hydroxyl groups which interact with nanoparticles from nucleation, growth, and termination giving rise to nonspherical shapes. The hydroxyl group promotes growth in a nonuniform way resulting in stars and rods. The optical features were typical of ZnO nanoparticles with excitonic peaks in the range 368 to 374 nm from their absorption spectra. The XRD patterns of the particles gave the most stable form of ZnO which is the hexagonal phase, with high degree of crystallinity and with the 101 plane predominant in all solvents.Phindile B. Khoza, Makwena J. Moloto, and Lucky M. SikhwivhiluCopyright © 2012 Phindile B. Khoza et al. All rights reserved.http://www.hindawi.com/journals/jnt/2012/401574/A hybrid magnesium alloy nanocomposite containing TiC nanoparticle reinforcement was fabricated using solidification processing followed by hot extrusion. The nanocomposite exhibited similar grain size to the monolithic hybrid alloy, reasonable TiC nanoparticle distribution, nondominant (0 0 0 2) texture in the longitudinal direction, and 16% higher hardness than the monolithic hybrid alloy. Compared to the monolithic hybrid alloy, the nanocomposite simultaneously exhibited higher tensile yield strength (0.2% TYS), ultimate tensile strength (UTS), failure strain, and work of fracture (WOF) (+14%, +7%, +81%, and +92%, resp.). Compared to the monolithic hybrid alloy, the nanocomposite exhibited lower compressive yield strength (0.2% CYS) and higher ultimate compressive strength (UCS), failure strain, and WOF (–11%, +7%, +4%, and +15%, resp.). The advantageous effects of TiC nanoparticle addition on the enhancement of tensile and compressive properties of the hybrid magnesium alloy are investigated in this paper.Muralidharan Paramsothy, Jimmy Chan, Richard Kwok, and Manoj GuptaCopyright © 2012 Muralidharan Paramsothy et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/702130/An enormous enhancement in the photo-to-current conversion efficiency over the nanocomposite material composed by BiVO4 on the surface of MWCNTs, with respect to electrode of pure BiVO4, was observed. The heterojunction formed between MWCNTs and nano-BiVO4 is beneficial for the separation of photogenerated electrons and holes, resulting in more electrons that are able to transport efficiently to the surface and therefore enhance the photoefficiency.Yan Zhang, Jianqiang Yu, Hongwei Wang, Mengmeng Sun, Yuyu Bu, Deshuang Yu, and Weibing LiCopyright © 2011 Yan Zhang et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/380979/The conventional superhydrophobic surface offered by PTFE provides no sterilization performance and is not sufficiently repellent against organic liquids. These limit PTFE's application in the field of disinfection and result a lack of durability. N-doped TiO2 photocatalyst added PTFE composite material was developed to remedy these shortcomings. This paper reports the surface characteristics, and the bactericidal and self-cleaning performance of the newly-developed composite material. The material exhibited a contact angle exceeding 150 degrees consistent with its hydrophobicity despite the inclusion of the hydrophilic N-doped TiO2. The surface free energy obtained for this composite was 5.8 mN/m. Even when exposed to a weak fluorescent light intensity (100 lx) for 24 hours, the viable cells of gram-negative E. coli on the 12% N-doped TiO2-PTFE film were reduced 5 logs. The higher bactericidal activity was also confirmed on the gram-positive MRSA. Compared with the N-doped TiO2 coating only, the inactivation rate of the composite material was significantly enhanced. Utilizing the N-doped TiO2 with the PTFE composite coating could successfully remove, by UV illumination, oleic acid adsorbed on its surface. These results demonstrate the potential applicability of the novel N-doped TiO2 photocatalyst hydrophobic composite material for both indoor antibacterial action and outdoor contamination prevention.Kentaro Yamauchi, Yanyan Yao, Tsuyoshi Ochiai, Munetoshi Sakai, Yoshinobu Kubota, and Goro YamauchiCopyright © 2011 Kentaro Yamauchi et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/961630/We have explored the direct use of anodized alumina (AAO) fabricated on an Si wafer as a mold for the nanoimprint lithography (NIL). The AAO mold has been fabricated over more than 10 cm2 area with two different pore diameters of 163±24 nm and 73±7 nm. One of the key challenges of the lack of bonding between the antisticking self-assembled monolayer (SAM) and the AAO has been overcome by modifying the surface chemistry of the fabricated AAO mold by coating it with thin SiO2 layer. Then we have applied the commonly used silane-based self-assembled monolayer (SAM) on these SiO2-coated AAO molds and achieved successful imprinting of resist pillars with feature size of 172±25 nm by using the mold with a pore diameter of 163±24 nm. Finally, we have achieved (001) oriented L10 FePt patterned structure with a dot diameter of 42±4 nm by using a AAO mold with a pore diameter of 73±7 nm. The perpendicular Hc of the unpatterned and patterned FePt is about 3.3 kOe and 12 kOe, respectively. These results indicate that AAO mold can potentially be used in NIL for fabricating patterned nanostructures over large area.M. Tofizur Rahman, Hao Wang, and Jian-Ping WangCopyright © 2011 M. Tofizur Rahman et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/631753/The mastery of active tumor targeting is a great challenge in near infrared photothermal therapy (NIRPTT). To improve efficiency for targeted treatment of malignant tumors, we modify the technique of conjugating gold nanoparticles to tumor-specific antibodies. Polyethylene glycol-coated (PEGylated) gold nanorods (GNRs) were fabricated and conjugated to an anti-EGFR antibody. We characterized the conjugation efficiency of the GNRs by comparing the efficiency of antibody binding and the photothermal effect of the GNRs before and after conjugation. We demonstrate that the binding efficiency of the antibodies conjugated to the PEGylated GNRs is comparable to the binding efficiency of the unmodified antibodies and 33.9% greater than PEGylated antibody-GNR conjugates as reported by Liao and Hafner (2005). In addition, cell death by NIRPTT was sufficient to kill nearly 90% of tumor cells, which is comparable to NIRPTT with GNRs alone confirming that NIRPTT using GNRs is not compromised by conjugation of GNRs to antibodies.Hadiyah N. Green, Dmitry V. Martyshkin, Cynthia M. Rodenburg, Eben L. Rosenthal, and Sergey B. MirovCopyright © 2011 Hadiyah N. Green et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/617196/Nanobiosensors are devices which incorporate nanomaterials to detect miniscule quantities of biological and chemical agents. The authors have already developed a novel bionanosensor (BNS) for quick, efficient, and precise detection of bacterial pathogens using the principles of CNT-DNA interaction and DNA hybridization. The detection ability of the (BNS) was observed to be independent of the device resistance. Two new methods (low-pass filter (LPF) and curve fitting (CF)) were developed for better analysis of the BNS. These methods successfully model the BNS. Evidence is provided to elucidate the success of the model, which can explain the DNA hybridization on the sensor surface. These models successfully demonstrated the detection of DNA hybridization versus nonhybridization. Thus, the models can not only help in better and efficient design and operation of the BNS, but can also be used to analyze other similar nanoscale devices.Vishal Desai, Srisowmya Sanisetty, Benjamin Steber, Eva Sapi, Bouzid Aliane, Saion Sinha, and Prabir PatraCopyright © 2011 Vishal Desai et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/506862/A bimetallic Pt-Ru nanoparticle catalyst was prepared and characterized for the enhancement of hydrogen peroxide (H2O2) detection in biosensing applications. The particles were synthesized via sodium borohydride reduction, with low heat treatment, and characterized by TEM and HRTEM. The chemical composition analyses were performed by EDX. The bimetallic particle diameters ranged from 2 to 12 nm, with an average of 4.5 nm. The Pt-Ru catalyst exhibited an improved performance at low overpotential (+0.2 V versus Ag/AgCl reference electrode) in H2O2 detection, suggesting a sensitivity value of 78.95 μA⋅mM-1 (or 402.1 μA⋅mM-1⋅cm-2) which was 30% higher than that for the single Pt catalyst. The major contribution of this enhancement comes from the stronger oxygen adsorption on Ru metal. The Pt-Ru catalyst also showed a more stable signal at the high overpotential (+0.4 V versus Ag/AgCl), providing better accuracy in the detection of H2O2.Metini Janyasupab, Yuan Zhang, Po-Yuan Lin, Brandon Bartling, Jiaqiang Xu, and Chung-Chiun LiuCopyright © 2011 Metini Janyasupab et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/408151/Silver nanoparticles were spontaneously formed on pristine and oxidized single-wall nanotubes. Nanoparticles were observed on carbon nanotubes with AFM, and the presence of Ag nanoparticles were confirmed by ESR experiments. Raman spectroscopy of the Ag-treated carbon nanotubes had a 4–10X enhancement of intensity compared to untreated carbon nanotubes. Ag nanoparticles formed at defect sites on the CNT surface, where free electrons located at the defect sites reduced Ag+ to Ag. A mechanism for the propagation of the nanoparticles is through a continual negative charge generation on the nanoparticle by electron transfer from doublet oxygen (O2−).Jason Maley, Gabriele Schatte, Jian Yang, and R. SammynaikenCopyright © 2011 Jason Maley et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/569036/Nanostructured Sn-doped TiO2 have been prepared by ball milling using SnO2 and TiO2 as raw materials. The as-prepared powders are characterized by XRD, SEMs and EDAX to identify the structural phases, surface morphology, and composition of the materials. The materials are prepared with the addition of tin of different molar ratios (0, 0.05, 0.10, 0.15, 0.20, 0.25, and 1.0) to TiO2 and sintered at 800°C for 3 h. They are subjected to dc resistance measurements as a function of relative humidity (RH) in the range of 30%–97% in a self-designed humidity chamber, and the results revealed that the sensitivity factor increased with an increase in tin molar ratio. Among them, TiO2—20 wt% of SnO2 possessed the highest humidity sensitivity, while the pure TiO2 and SnO2 composite possessed a low sensitivity.P. Raji, H. S. Binitha, and K. Balachandra KumarCopyright © 2011 P. Raji et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/461313/A new alkyd paint anticorrosion smart coating was developed by using silica nanoparticles as corrosion inhibitor nanocontainers. Silica particles were mixed with the paint at different concentrations to study their performance and ensure their free transportation to the damaged metal. The filling up of silica particles was done preparing three solutions: distilled water, acetone, and a mixture of both, with Fe(NO3)3 and silica particles immersed in each of the solutions to adsorb the inhibitor. Acetone solution was the best alternative determined by weight gain analysis made with the inhibitor adsorbed in silica nanocontainers. Steel samples were painted with inhibitor silica nanocontainer coatings and immersed in an aqueous solution of 3% sodium chloride. Polarization curves and electrochemical noise techniques were used to evaluate the corrosion inhibitor system behavior. Good performance was obtained in comparison with samples without inhibitor nanocontainer coating.Cesia Ávila-Gonzalez, Rodolfo Cruz-Silva, Carmina Menchaca, Selene Sepulveda-Guzman, and Jorge UruchurtuCopyright © 2011 Cesia Ávila-Gonzalez et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/471241/The electronic band structure variations of single-walled carbon nanotubes (SWCNTs) using Huckle/tight binding approximation theory are studied. According to the chirality indices, the related expressions for energy dispersion variations of these elements are derived and plotted for zigzag and chiral nanotubes.Davood FathiCopyright © 2011 Davood Fathi. All rights reserved.http://www.hindawi.com/journals/jnt/2011/823680/We report an all-printed thin-film transistor (TFT) on a polyimide substrate with linear transconductance response. The TFT is based on our purified single-walled carbon nanotube (SWCNT) solution that is primarily consists of semiconducting carbon nanotubes (CNTs) with low metal impurities. The all-printed TFT exhibits a high ON/OFF ratio of around 103 and bias-independent transconductance over a certain gate bias range. Such bias-independent transconductance property is different from that of conventional metal-oxide-semiconductor field-effect transistors (MOSFETs) due to the special band structure and the one-dimensional (1D) quantum confined density of state (DOS) of CNTs. The bias-independent transconductance promises modulation linearity for analog electronics.Guiru Gu, Yunfeng Ling, Runyu Liu, Puminun Vasinajindakaw, Xuejun Lu, Carissa S. Jones, Wu-Sheng Shih, Vijaya Kayastha, Nick L. Downing, Xuliang Han, Harish Subbaraman, Dan Pham, Ray T. Chen, Maggie Yihong Chen, Urs Berger, and Mike RennCopyright © 2011 Guiru Gu et al. All rights reserved.http://www.hindawi.com/journals/jnt/2012/794874/The NiO/SnO2 nanocomposites have been prepared by the simple coprecipitation method and further characterized by the XRD, SEM, TEM, UV-Vis, and BET. X-ray diffraction (XRD) data analyses indicate the exclusive formation of nanosized particles with rutile-type phase (tetragonal SnO2) for Ni contents below 10 mol%. Only above 10 mol% Ni, the formation of a second NiO-related phase has been determined. The particle size is in the range from 12 to 6 nm. It decreases with increasing amounts of doping NiO. The morphology of NiO-doped SnO2 nanocrystalline powders is spherical, and the distribution of particle size is uniform, as seen from transmission electron microscopy (TEM). The photocatalytic oxidation of CO over NiO/SnO2 photocatalyst has been investigated under UV irradiation. Effects of NiO loading on SnO2, photocatalyst loading, and reaction time on photocatalytic oxidation of CO have been systematically studied. Compared with pure SnO2, the 33.3 mol% NiO/SnO2 composite exhibited approximately twentyfold enhancement of photocatalytic oxidation of CO. Our results provide a method for pollutants removal. Due to simple preparation, high photocatalytic oxidation of CO, and low cost, the NiO/SnO2 photocatalyst will find wide application in the coming future of photocatalytic oxidation of CO.R. M. Mohamed and Elham S. AazamCopyright © 2012 R. M. Mohamed and Elham S. Aazam. All rights reserved.http://www.hindawi.com/journals/jnt/2011/342368/A route to area-selective deposition of carbon-coated iron nanoparticles, involving chemical modification of the surface of the particles, is described. Partial oxidative etching of the coating introduces carboxylic groups, which then are esterified. The functionalized particles can be selectively deposited on the Si areas of Si/SiO2 substrates by a simple dipping procedure. Nanoparticles and nanoassemblies have been analyzed using SEM, TEM, and XPS.Erika Widenkvist, Oscar Alm, Mats Boman, Ulf Jansson, and Helena GrennbergCopyright © 2011 Erika Widenkvist et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/986021/Silver-copper-oxide thin films were formed by RF magnetron sputtering technique using Ag80Cu20 target at various oxygen partial pressures in the range 5 × 10−3–8 ×10−2 Pa and substrate temperatures in the range 303–523 K. The effect of oxygen partial pressure and substrate temperature on the structure and surface morphology and electrical and optical properties of the films were studied. The Ag-Cu-O films formed at room temperature (303 K) and at low oxygen partial pressure of 5 × 10−3 Pa were mixed phase of Ag2Cu2O3 and Ag, while those deposited at 2 × 10−2 Pa were composed of Ag2Cu2O4 and Ag2Cu2O3 phases. The crystallinity of the films formed at oxygen partial pressure of 2 × 10−2 Pa increased with the increase of substrate temperature from 303 to 423 K. Further increase of substrate temperature to 523 K, the films were decomposed in to Ag2O and Ag phases. The electrical resistivity of the films decreased from 0.8 Ωcm with the increase of substrate temperature from 303 to 473 K due to improvement in the crystallinity of the phase. The optical band gap of the Ag-Cu-O films increased from 1.47 to 1.83 eV with the increase of substrate temperature from 303 to 473 K.P. Narayana Reddy, A. Sreedhar, M. Hari Prasad Reddy, S. Uthanna, and J. F. PiersonCopyright © 2011 P. Narayana Reddy et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/924582/We studied a hydrophilic, plasticized bionanocomposite system involving sorbitol plasticizer, amylose biopolymer, and montmorillonite (MMT) for the presence of competitive interactions among them at different moisture content. Synchrotron analysis via small angle X-ray scattering (SAXS) and thermal analysis using differential scanning calorimetry (DSC) were performed to understand crystalline growth and the distribution of crystalline domains within the samples. The SAXS diffraction patterns showed reduced interhelix spacing in the amylose network indicating strong amylose-sorbitol interactions. Depending on the sorbitol and MMT concentration, these interactions also affected the free moisture content and crystalline domains. Domains of around 95 Å and 312 Å were found in the low-moisture-content samples as compared to a single domain of 95 Å in the high-moisture-content samples. DSC measurements confirmed that the MMT increased the onset and the melting temperature of nanocomposites. Moreover, the results showed that the ternary interactions among sorbitol-amylose-MMT supported the crystalline heterogeneity through secondary nucleation.Huihua Liu, Deeptangshu Chaudhary, Joseph John, and Moses O. TadéCopyright © 2011 Huihua Liu et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/727396/To increase the performance of photochemical fuel cells, nonequilibrium electrodeposition has been performed on Cu and Ni to make photosensitive anodes. Processing parameters including electrolyte concentration, and electrode potential were studied using cyclic voltammetry. Scanning electron microscopy (SEM) and X-ray Spectroscopy (EDS) were performed to understand the formation of the nanostructures during the nonequilibrium deposition of copper fractals. An increase in the deposition rate was observed with the increase in electrolyte concentration (from 0.05 M to 1.0 M). Similar trend was found when the cathode potential was decreased from −0.5 V to −4.5 V. The effect of substrate material was also examined. Porous fractal structures on copper were achieved, while the deposited material showed high density of surface cracks on nickel. The fractal structures deposited on copper electrode with the increased surface area were converted into copper oxide by oxidation in air. Such oxide samples were made into anodes for photochemical fuel cell application. We demonstrated that an increase in the magnitude of open circuit output voltage is associated with the increase in the fractal surface area under the ultraviolet irradiation test conditions. However, the electrodeposited fractals on nickel showed very limited increase in the magnitude of open circuit voltage.Rajesh K. Shanmugam, Bo J. Gan, Boya Zhang, Lusheng Su, and Yong X. GanCopyright © 2011 Rajesh K. Shanmugam et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/696535/The present study demonstrates an effect of nano-ZnO particles on the growth of plant seedlings of mung (Vigna radiate) and gram (Cicer arietinum). The study was carried out in plant agar media to prevent precipitation of water-insoluble nanoparticles in the test units. Various concentrations of nano-ZnO particles in suspension form were introduced to the agar media, and their effect on the root and shoot growth of the seedlings was examined. The main experimental approach, using correlative light and scanning electron microscopy provided evidence of adsorption of nanoparticles on the root surface. Absorption of nanoparticles by seedlings root was also detected by inductive coupled plasma/atomic emission spectroscopy (ICP-AES). It was found that at certain optimum concentration, the seedlings displayed good growth over control, and beyond that, retardation in growth was observed.Pramod Mahajan, S. K. Dhoke, and A. S. KhannaCopyright © 2011 Pramod Mahajan et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/952846/Nanoscale objects often behave differently than their “normal-sized” counterparts. Sometimes it is enough to be small in just one direction to exhibit unusual features. One example of such a phenomenon is a very specific in-plane magnetic anisotropy observed sometimes in very thin layers of various materials. Here we recall a peculiar form of the free energy functional nicely describing the experimental findings but completely irrelevant and thus never observed in larger objects.Marek W. GutowskiCopyright © 2011 Marek W. Gutowski. All rights reserved.http://www.hindawi.com/journals/jnt/2011/203423/Using first-principles methods we performed a theoretical study of carbon clusters in silicon carbide (SiC) nanowires. We examined small clusters with carbon interstitials and antisites in hydrogen-passivated SiC nanowires growth along the [100] and [111] directions. The formation energies of these clusters were calculated as a function of the carbon concentration. We verified that the energetic stability of the carbon defects in SiC nanowires depends strongly on the composition of the nanowire surface: the energetically most favorable configuration in carbon-coated [100] SiC nanowire is not expected to occur in silicon-coated [100] SiC nanowire. The binding energies of some aggregates were also obtained, and they indicate that the formation of carbon clusters in SiC nanowires is energetically favored.J. M. Morbec and R. H. MiwaCopyright © 2011 J. M. Morbec and R. H. Miwa. All rights reserved.http://www.hindawi.com/journals/jnt/2011/242398/Hydrogenated nanocrystalline silicon films were prepared by hot-wire method at low substrate temperature (200∘C) without hydrogen dilution of silane (SiH4). A variety of techniques, including Raman spectroscopy, low angle X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, atomic force microscopy (AFM), and UV-visible (UV-Vis) spectroscopy, were used to characterize these films for structural and optical properties. Films are grown at reasonably high deposition rates (>15 Å/s), which are very much appreciated for the fabrication of cost effective devices. Different crystalline fractions (from 2.5% to 63%) and crystallite size (3.6–6.0 nm) can be achieved by controlling the process pressure. It is observed that with increase in process pressure, the hydrogen bonding in the films shifts from Si–H to Si–H2 and (Si–H2)n complexes. The band gaps of the films are found in the range 1.83–2.11 eV, whereas the hydrogen content remains <9 at.% over the entire range of process pressure studied. The ease of depositing films with tunable band gap is useful for fabrication of tandem solar cells. A correlation between structural and optical properties has been found and discussed in detail.V. S. Waman, A. M. Funde, M. M. Kamble, M. R. Pramod, R. R. Hawaldar, D. P. Amalnerkar, V. G. Sathe, S. W. Gosavi, and S. R. JadkarCopyright © 2011 V. S. Waman et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/916750/Bright ZnS : Mn2+ nanoparticles have been synthesized employing microwave irradiation technique and using zinc 2-ethylhexanoate as a novel zinc precursor. A series of samples is obtained by changing the microwave power (from 150 W to 500 W) to study its effect on the physical properties of the ZnS : Mn2+ nanoparticles. The particle size increases with increasing microwave power for the samples synthesized in the microwave range of 150 W to 300 W. The decrease in particle size for higher microwave power (400 W and 500 W) can be described as an onset of the secondary nucleation due to the excess energy associated with the higher microwave power. The sample synthesized with microwave power of 300 W shows highest luminescence intensity suggesting increase in Mn2+ luminescence center for the sample synthesized at 300 W, as supported by the quantity analysis results.Baibaswata Bhattacharjee and Chung-Hsin LuCopyright © 2011 Baibaswata Bhattacharjee and Chung-Hsin Lu. All rights reserved.http://www.hindawi.com/journals/jnt/2011/904629/TiO2 nanotubes immobilized on silica gel were used in the photocatalytic degradation of phenol in a batch reactor. The highest rate of photocatalytic activity was observed when the ratios of TiO2 nanotubes: silica gel: colloidal silica were 3 : 2 : 20. The optimal air flow rate for phenol degradation was 0.3 L/min while pH 3 was optimal for the reaction medium. Decreasing the initial phenol concentration led to an increase in phenol degradation efficiency due to more hydroxyl radicals being presented on the catalyst surface. Immobilized TiO2 nanotubes showed higher photocatalytic activity than that of the pure TiO2 which only achieved 87% degradation. Compared with pure TiO2, the immobilized TiO2 nanotubes benefited from a larger specific surface area and a low recombination rate of photogenerated electron-hole pairs. After three operating cycles, the decrease in photocatalytic activity of the immobilized TiO2 nanotubes was slight, indicating that the immobilized TiO2 nanotubes have excellent stability and reusability.Chung Leng Wong, Yong Nian Tan, and Abdul Rahman MohamedCopyright © 2011 Chung Leng Wong et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/637395/We have investigated strain hardening behavior of ultrahigh molecular weight polyethylene (UHMWPE) reinforced with 2.0 wt% loading of multiwalled carbon nanotubes (MWCNTs). A solution spinning process was used to produce neat and MWCNT-reinforced filaments of UHMWPE. Tensile tests of filaments showed 62% and 114% improvement in strength and modulus, respectively. Strain hardening tests on filaments revealed spectacular contribution by MWCNTs in enhancing strength and modulus by more than one order of magnitude. SEM micrographs showed sufficient coating of nanotube surface with the polymer that promoted interface adhesion. This intimate interfacial interaction enforced alignment of nanotubes during repeated loading-unloading sequences and allowed effective load transfer to nanotubes. Close interaction between UHMWPE and nanotubes was further evidenced by Raman spectral distribution as a positive shift in the D-band suggesting compressive stress on nanotubes by lateral compression of polymer. Nanotubes thus deformed induced the desired strain hardening ability in the UHMWPE filament. Differential scanning calorimetry (DSC) tests indicated around 15% increase in crystallinity after strain hardening—which together with nanotube alignment resulted in such dramatic improvement in properties.Hassan Mahfuz, Mujibur R. Khan, Theodora Leventouri, and Efthymios LiarokapisCopyright © 2011 Hassan Mahfuz et al. All rights reserved.http://www.hindawi.com/journals/jnt/2011/386582/This paper reports tungsten-platinum hybrid nanowire growth via field emission, based on nanorobotic manipulation within a field emission scanning electron microscope (FESEM). A multiwalled carbon nanotube (MWCNT) was used as the emitter, and a tungsten probe was used as the anode at the counterposition, by way of nanomanipulation. By independently employing trimethylcyclopentadienyl platinum (CpPtMe3) and tungsten hexacarbonyl (W(CO)6) as precursors, the platinum nanowire grew on the tip of the MWCNT emitter. Tungsten nanowires then grew on the tip of the platinum nanowire. The hybrid nanowire length wascontrolled by nanomanipulation. Their purity was evaluated using energy-dispersive X-ray spectroscopy (EDS). Thus, it is possible to fabricate various metallic hybrid nanowires by changing the precursor materials. Hybrid nanowires have various applications in nanoelectronics, nanosensor devices, and nanomechanical systems.Zhan Yang, Masahiro Nakajima, Yasuhito Ode, and Toshio FukudaCopyright © 2011 Zhan Yang et al. All rights reserved.