Journal of Nanomaterials http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2015 , Hindawi Publishing Corporation . All rights reserved. Physicochemical Analysis of the Polydimethylsiloxane Interlayer Influence on a Hydroxyapatite Doped with Silver Coating Thu, 28 May 2015 13:08:29 +0000 http://www.hindawi.com/journals/jnm/2015/250617/ We investigate by different complementary methods the processes occurring when a polydimethylsiloxane film is used as interlayer for a silver doped hydroxyapatite coating. The X-ray diffraction and Fourier Transform Infrared Spectroscopy measurements show that the hydroxyapatite doped with silver is in a crystalline form and some ions formation takes place at the surface and in the bulk of the new hydroxyapatite doped with silver/polydimethylsiloxane composite layer. The possibility of ions incorporation in the structure of silver doped hydroxyapatite by the mechanism of / ions substitution is analysed. The new formed silver doped hydroxyapatite/polydimethylsiloxane composite layer is compact, homogeneous, with no cracks as it was shown by Scanning Electron Microscopy and Glow Discharge Optical Emission Spectrometry. C. L. Popa, A. Groza, P. Chapon, C. S. Ciobanu, R. V. Ghita, R. Trusca, M. Ganciu, and D. Predoi Copyright © 2015 C. L. Popa et al. All rights reserved. Rapid Formation of 1D Titanate Nanotubes Using Alkaline Hydrothermal Treatment and Its Photocatalytic Performance Thu, 28 May 2015 11:59:59 +0000 http://www.hindawi.com/journals/jnm/2015/145360/ One-dimensional (1D) titanate nanotubes (TNT) were successfully synthesized using alkaline hydrothermal treatment of commercial TiO2 nanopowders in a Teflon lined stainless steel autoclave at 150°C. The minimum time required for the formation of the titanate nanotubes was 9 h significantly. After the hydrothermal processing, the layered titanate was washed with acid and water in order to control the amount of Na+ ions remaining in the sample solutions. In this study, the effect of different reaction durations in a range of 3 h to 24 h on the formation of nanotubes was carried out. As the reaction duration is extended, the changes in structure from particle to tubular shapes of alkaline treated TiO2 were obtained via scanning electron microscope (SEM). Also, the significant impact on the phase transformation and crystal structure of TNT was characterized through XRD and Raman analysis. Indeed, the photocatalytic activity of TNT was investigated through the degradation of methyl orange aqueous solution under the ultraviolet light irradiation. As a result, TNT with reaction duration at 6 h has a better photocatalytic performance than other samples which was correlated to the higher crystallinity of the samples as shown in XRD patterns. Chin Wei Lai, Sharifah Bee Abd Hamid, Tong Ling Tan, and Wai Hong Lee Copyright © 2015 Chin Wei Lai et al. All rights reserved. Comparison of the Effect of Sol-Gel and Coprecipitation Routes on the Properties and Behavior of Nanocomposite Chitosan-Bioactive Glass Membranes for Bone Tissue Engineering Thu, 28 May 2015 11:18:13 +0000 http://www.hindawi.com/journals/jnm/2015/150394/ Recent studies in tissue engineering have highlighted the importance of the development of composite materials based on biodegradable polymers containing bioactive glasses, in particular, composites for high load support and excellent cell viability for potential application in bone regeneration. In this work, hybrid composite films were obtained by combining chitosan with bioactive glass in solution form and in nanoparticle dispersion form obtained by the two different synthesis routes: the sol-gel method and coprecipitation. The bioactive glass served both as a mechanical reinforcing agent and as a triggering agent with high bioactivity. The results of in vitro assays with simulated body fluid demonstrated the formation of a significant layer of fibrils on the surface of the film, with a typical morphology of carbonated hydroxyapatite, reflecting induction of a favorable bioactivity. Maximum tensile stress increased from 42 to 80 MPa to the sample with 5% wt bioactive glass. In addition, samples containing 5% and 10% wt bioactive glass showed a significant increase in cell viability, 18 and 30% increase compared to the control group. The samples showed significant response, indicating that they could be a potential material for use in bone regeneration through tissue engineering. Elke M. F. Lemos, Sandhra M. Carvalho, Patrícia S. O. Patrício, Claudio L. Donnici, and Marivalda M. Pereira Copyright © 2015 Elke M. F. Lemos et al. All rights reserved. Failure Mechanisms of a Gold Microelectrode in Bioelectronics Applications Thu, 28 May 2015 09:24:53 +0000 http://www.hindawi.com/journals/jnm/2015/792198/ The generation, growth, and collapse of tiny bubbles are inevitable for a microelectrode working in aqueous environment, thus resulting in physical damages on the microelectrode. The failure mechanisms of a microelectrode induced by tiny bubble collapsing are investigated by generating tiny hydrogen bubbles on a gold microelectrode through deionized water electrolysis. The surface of the microelectrode is modified with a thiol-functionalized arginine-glycine-aspartic acid peptide to generate perfectly spherical bubbles in proximity of the surface. The failure of an Au microelectrode is governed by two damage mechanisms, depending on the thickness of the microelectrode: a water-hammer pressure due to the violent collapse of a single large bubble, formed through merging of small bubbles, for ultrathin Au microelectrodes of 40–60 nm in thickness, and an energy accumulation resulting from the repetitive collapse of tiny bubbles for thick Au microelectrodes of 100–120 nm. Jonghun Kim and Sang-Hee Yoon Copyright © 2015 Jonghun Kim and Sang-Hee Yoon. All rights reserved. Application of Biosynthesized Silver Nanoparticles for the Control of Land Snail Eobania vermiculata and Some Plant Pathogenic Fungi Thu, 28 May 2015 09:18:12 +0000 http://www.hindawi.com/journals/jnm/2015/218904/ The land snail Eobania vermiculata is an important crop pest causing considerable damage in agriculture. The aim of the present work is to evaluate the possibilities of using silver nanoparticles (AgNPs) to control the land snail. The AgNPs have been synthesized biologically using white radish (Raphanus sativus var. aegyptiacus). The biosynthesis was regularly monitored by UV-Vis spectroscopy. X-ray diffraction spectra revealed peaks of crystalline nature of AgNPs and the transmission electron micrographs further confirmed the size of the synthesized nanoparticles ranging from 6 to 38 nm. The exposure of the snails and soil matrix to AgNPs in a laboratory experiment reduced the activity and the viability of the land snail (20% of AgNPs treated snails died) as well as the frequency of fungal population in the surrounding soil. Moreover histology and ultrastructure alterations have been found in both kidney and the digestive gland of AgNPs treated land snails. The synergistic effect of synthesized AgNPs as antifungal was evaluated and clearly revealed that AgNPs can be effectively used against various plant pathogenic fungi. The present study results may open a new avenue to use the snail as bioindicator organism of environmental pollution. Safaa M. Ali, Naeima M. H. Yousef, and Nivien A. Nafady Copyright © 2015 Safaa M. Ali et al. All rights reserved. Degradation Kinetics of Photoelectrocatalysis on Landfill Leachate Using Codoped TiO2/Ti Photoelectrodes Thu, 28 May 2015 09:06:30 +0000 http://www.hindawi.com/journals/jnm/2015/810579/ The photoelectrocatalytic (PEC) oxidation degradation of landfill leachate rejected by reverse osmosis (RO) using a Cu/N codoped TiO2/Ti photoelectrode was kinetically investigated in terms of COD concentration. The key factors affecting the reaction rate of PEC oxidation and the removal efficiency of COD concentration were studied, including the COD concentration of landfill leachate, potential bias applied, pH value of landfill leachate, and the reaction temperature of photoelectrocatalytic reactor. The apparent kinetic model was applied to describe the photoelectrocatalysis reaction. The results showed that the kinetic equation for photoelectrocatalytic oxidation of landfill leachate was fitting well with the experimental data ( 0.967~0.998), with average activation energy 6.35 × 104 Jmol−1. It was found that there was an optimal bias voltage of 20 V and low pH value was favorable for COD removal in landfill leachate. The reaction order of initial COD concentration (1.326) is higher than that of potential bias (1.102) and pH value (0.074), which indicates that the reaction rate can be controlled efficiently through adjusted initial concentration. The experiments demonstrated that potential bias would approach its statured value with increasing potential bias. Xiao Zhou, Yongxin Zheng, Juan Zhou, and Shaoqi Zhou Copyright © 2015 Xiao Zhou et al. All rights reserved. Toxicity of Nanoparticles against Drosophila melanogaster (Diptera: Drosophilidae) Thu, 28 May 2015 09:05:49 +0000 http://www.hindawi.com/journals/jnm/2015/758132/ In recent years, nanotechnology has become one of the most promising new approaches for pest control. In our screening program, laboratory trials were conducted to determine the effectiveness of five sources of silver nanoparticles (Ag NPs) and sulfur nanoparticles (S NPs) on larval, pupal, and adults of the fruit fly Drosophila melanogaster. Nanoparticles of silver and sulfur were synthesized through reducing, stabilizing, and capping plant leaf extracts method and different concentrations (10, 50, 100, 200 ppm) were tested on D. melanogaster. Results showed that silver nanoparticles (Ag NPs) were highly effective on larvae, pupae, and adults’ mortality and egg deterrence. On the contrary, none of the tested nanoparticles has a significant effect on pupae longevity. The results also showed that silver nanoparticles can be used as a valuable tool in pest management programs of D. melanogaster. Salah-Eddin A. Araj, Nida’ M. Salem, Ihab H. Ghabeish, and Akl M. Awwad Copyright © 2015 Salah-Eddin A. Araj et al. All rights reserved. Catalytic Rapid Pyrolysis of Quercus variabilis over Nanoporous Catalysts Thu, 28 May 2015 09:04:10 +0000 http://www.hindawi.com/journals/jnm/2015/251974/ Catalytic rapid pyrolysis of Quercus variabilis, a Korean native tree species, was carried out using Py-GC/MS. Mesoporous MFI, which has both nanopores and micropores, and three nanoporous materials, Al-MCM-41, Al-SBA-15, and γ-Al2O3, were used as the catalyst. The acid sites of mesoporous MFI were strong Brønsted acid sites, whereas those of nanoporous materials were mostly weak acid sites. The composition of the product bio-oil varied greatly depending on the acid characteristics of the catalyst used. Phenolics were the most abundant species in the bio-oil, followed by acids and furanics, obtained over Al-MCM-41 or Al-SBA-15 with weak acid sites, whereas aromatics were the most abundant species produced over mesoporous MFI with strong acid sites, followed by phenolics. Aromatics, phenolics, and furanics are all important chemicals contributing to the improvement of bio-oil quality. Hyeon Koo Kang, In-Gu Lee, Kyong-Hwan Lee, Beom-Sik Kim, Tae Su Jo, Kwang-Seok Chea, Sung Hoon Park, Sang-Chul Jung, and Young-Kwon Park Copyright © 2015 Hyeon Koo Kang et al. All rights reserved. Effectiveness of Two Self-Etchings Bonded Clinically in Caries Affected Dentin with Homogeneous Smear Layer Thu, 28 May 2015 08:57:47 +0000 http://www.hindawi.com/journals/jnm/2015/489183/ Aim. To examine the interface of two self-etchings in carious affected dentin (CAD), under clinical conditions. Materials and Methods. Class I cavities were prepared in 21 carious premolars, refining them by the use of a fine diamond bur in order to create similar smear layer interference. The mild self-etching Clearfil SE Bond (CSE), pH = 2.0, and the strong Tyrian SPE-One Step Plus (TSO), pH = 0.5, were applied followed by a composite. Teeth were extracted and processed for TEM. The primer’s osmolarity of the self-etchings was also calculated using a microosmometer. Results. CSE hybrid layer retained smear layer residues and scattered crystallites as an effect of the mild acidity. A high presence of hydroxyapatite still protected the affected fibres within the hybrid layer. CSE primer demonstrated values of 3220 mOsm/kg. TSO interdiffusion showed strong demineralization. Resin tags were not formed in the dentinal tubules which remained obstructed by crystals. However, dissolution of peritubular dentin and porosities were observed in the intertubular regions. The osmolarity of TSO was 8200 mOsm/kg. Conclusion. Increasing the acidity and osmolarity of the self-etchings increases interference in the homogeneous reinforcement of CAD, which may predispose the hybrid layer to instability and hydrolytic degradation overtime. Roberto Pinna, Paolo Usai, Mariantonietta Arrica, and Egle Milia Copyright © 2015 Roberto Pinna et al. All rights reserved. Assaying Biomarkers via Real-Time Measurements of the Effective Relaxation Time of Biofunctionalized Magnetic Nanoparticles Associated with Biotargets Thu, 28 May 2015 07:26:33 +0000 http://www.hindawi.com/journals/jnm/2015/497296/ An assay of biomarkers consisting of alpha-fetoprotein (AFP) is reported. Real-time measurements of the effective relaxation time , when the biofunctionalized magnetic nanoparticles (BMNs) were conjugating with biotargets, were made. The BMNs are anti-alpha-fetoprotein (antiAFP) coated onto dextran-coated iron oxide nanoparticles labeled as Fe3O4-antiAFP. It was found that the effective relaxation time, , increases as the association of AFP and Fe3O4-antiAFP evolves. We attribute this to the enhanced Brownian motion of BMNs when magnetic clusters are present during the conjugation. We found that saturation magnetization, , increases when the concentration of AFP increases. This is due to the fact that more magnetic clusters are associated in the reagent, and therefore the increases when the concentration of AFP increases. The change of effective relaxation time and saturation magnetization shows a behavior of logistic function, which provides a foundation for assaying an unknown amount of biomolecules. Thus, we demonstrate sensitive platforms for detecting AFP by characterizing . The detection platform is robust and easy to use and shows promise for further use in assaying a broad number of biomarkers. Shu-Hsien Liao, Jean-Hong Chen, Yu-Kai Su, Kuen-Lin Chen, Herng-Er Horng, and Hong-Chang Yang Copyright © 2015 Shu-Hsien Liao et al. All rights reserved. A Salt-Assisted Combustion Method to Prepare Well-Dispersed Octahedral MnCr2O4 Spinel Nanocrystals Thu, 28 May 2015 06:55:32 +0000 http://www.hindawi.com/journals/jnm/2015/214978/ Well-dispersed nanocrystalline MnCr2O4 was prepared by a salt-assisted combustion process using low-toxic glycine as fuel and Mn(NO3)2 and Cr(NO3)3·9H2O as raw materials. The obtained products were characterized by X-ray Diffraction (XRD), Fourier Transform Infrared (FT-IR) spectroscopy, Raman spectroscopy, Transmission Electron Microscopy (TEM), and Scanning Electron Microscopy (SEM). The fabrication process was monitored by thermogravimetric and differential thermal analysis (TG-DTA). The phase formation process was detected by XRD, and MnCr2O4 single phase with high crystallinity was formed at 700°C. TEM and SEM images revealed that the products were composed of well-dispersed octahedral nanocrystals with an average size of 80 nm. Inert salt-LiCl played an important role in breaking the network structure of agglomerated nanocrystallites. Yuping Tong, Juntao Ma, Shunbo Zhao, Hongyuan Huo, and Hailong Zhang Copyright © 2015 Yuping Tong et al. All rights reserved. Nanostructured Carbon Materials Thu, 28 May 2015 06:53:50 +0000 http://www.hindawi.com/journals/jnm/2015/916834/ Myoung-Woon Moon, Ho-Young Kim, Aiying Wang, and Ashkan Vaziri Copyright © 2015 Myoung-Woon Moon et al. All rights reserved. Mesoporous Structure Control of Silica in Room-Temperature Synthesis under Basic Conditions Thu, 28 May 2015 06:30:50 +0000 http://www.hindawi.com/journals/jnm/2015/149654/ Various types of mesoporous silica, such as continuous cubic-phase MCM-48, hexagonal-phase MCM-41, and layer-phase spherical silica particles, have been synthesized at room temperature using cetyltrimethylammonium bromide as a surfactant, ethanol as a cosurfactant, tetraethyl orthosilicate as a silica precursor, and ammonia as a condensation agent. Special care must be taken both in the filtering of the resultant solid products and in the drying process. In the drying process, further condensation of the silica after filtering was induced. As the surfactant and cosurfactant concentrations in the reaction mixture increased and the NH3 concentration decreased, under given conditions, continuous cubic MCM-48 and layered silica became the dominant phases. A cooperative synthesis mechanism, in which both the surfactant and silica were involved in the formation of mesoporous structures, provided a good explanation of the experimental results. Jeong Wook Seo, Woo-Jin Lee, Seongju Nam, Heekyoung Ryoo, Jong-Nam Kim, and Chang Hyun Ko Copyright © 2015 Jeong Wook Seo et al. All rights reserved. Preparation and Study of Electromagnetic Interference Shielding Materials Comprised of Ni-Co Coated on Web-Like Biocarbon Nanofibers via Electroless Deposition Wed, 27 May 2015 09:33:03 +0000 http://www.hindawi.com/journals/jnm/2015/320306/ Electromagnetic interference (EMI) shielding materials made of Ni-Co coated on web-like biocarbon nanofibers were successfully prepared by electroless plating. Biocarbon nanofibers (CF) with a novel web-like structure comprised of entangled and interconnected carbon nanoribbons were obtained using bacterial cellulose pyrolyzed at 1200°C. Paraffin wax matrix composites filled with different loadings (10, 20, and 30 wt%, resp.) of CF and Ni-Co coated CF (NCCF) were prepared. The electrical conductivities and electromagnetic parameters of the composites were investigated by the four-probe method and vector network analysis. From these results, the EMI shielding efficiencies (SE) of NCCF composites were shown to be significantly higher than that of CF at the same mass fraction. The paraffin wax composites containing 30 wt% NCCF showed the highest EMI SE of 41.2 dB (99.99% attenuation), which are attributed to the higher electrical conductivity and permittivity of the NCCF composites than the CF composites. Additionally, EMI SE increased with an increase in CF and NCCF loading and the absorption was determined to be the primary factor governing EMI shielding. This study conclusively reveals that NCCF composites have potential applications as EMI shielding materials. Xiaohu Huang, Bo Dai, Yong Ren, Jing Xu, and Pei Zhu Copyright © 2015 Xiaohu Huang et al. All rights reserved. A Comparison of the Performances of Different Mesoporous Titanias in Dye-Sensitized Solar Cells Wed, 27 May 2015 05:54:47 +0000 http://www.hindawi.com/journals/jnm/2015/450405/ The present work aims at optimizing titanium dioxide morphology for dye-sensitized solar cells applications. Five different anatase phase mesoporous titanias were prepared and tested as photoanodes in dye-sensitized solar cells. The materials were prepared by using a template approach. Two materials were synthesized by using monodisperse silica nanospheres and the other three using two different organic templating agents (Pluronic P123 and Brij 58). A complete characterization of the obtained materials was performed by powder XRD, FEG-SEM, UV-Vis reflectance spectroscopy, BET surface area measurements, and TG-DTA. Several cells were assembled using N719 as dye and a nonvolatile electrolyte based on benzonitrile. The cells were tested by means of J-V curves under simulated solar radiation, IPCE, and dark current measurements. The highest efficiencies were achieved with titania prepared by using Pluronic P123 as template (%), while the lowest efficiencies were recorded with using titania samples prepared with the silica nanospheres template (%). The different performances of the samples are examined and discussed. Alessandro Latini, Riccardo Panetta, Carmen Cavallo, Daniele Gozzi, and Simone Quaranta Copyright © 2015 Alessandro Latini et al. All rights reserved. Intratubular Antibacterial Effect of Polyethyleneimine Nanoparticles: An Ex Vivo Study in Human Teeth Tue, 26 May 2015 12:24:50 +0000 http://www.hindawi.com/journals/jnm/2015/980529/ Enterococcus faecalis is a facultative gram positive bacterium which can remain in the teeth root canals and cause refractory or persistent periapical diseases. E. faecalis bacteria that penetrate the dentinal tubules can be the source of intracanal infection and endodontic disease. Quaternary ammonium polyethyleneimine (QPEI) nanopolymers were shown to have long lasting antibacterial activity against gram positive and gram negative bacteria. The present study evaluated the intratubular antibacterial effect of an epoxy resin sealer incorporating 1% QPEI against E. faecalis in a human dentin model. Root canals of extracted teeth were inoculated with E. faecalis for 7 days prior to standard endodontic treatment. The antibacterial effect of an epoxy-amine resin endodontic sealer was tested at concentration of 0% or 1% (wt/wt) added QPEI nanoparticles. Reduction in bacterial viability was depicted in the dentinal tubules of the root canals obturated with the sealer incorporating QPEI nanoparticles. In conclusion, QPEI nanoparticles when incorporated in a small percentage into epoxy-resin based sealer may target E. faecalis in the dentinal tubules, producing a potent antibacterial effect that reduces significantly bacterial viability. Itzhak Abramovitz, Dekel Wisblech, Natan Zaltsman, Ervin I. Weiss, and Nurit Beyth Copyright © 2015 Itzhak Abramovitz et al. All rights reserved. Enhancement of Gas Sensing Characteristics of Multiwalled Carbon Nanotubes by CF4 Plasma Treatment for SF6 Decomposition Component Detection Tue, 26 May 2015 12:06:58 +0000 http://www.hindawi.com/journals/jnm/2015/171545/ H2S and SO2 are important gas components of decomposed SF6 of partial discharge generated by insulation defects in gas-insulated switchgear (GIS). Therefore, H2S and SO2 detection is important in the state evaluation and fault diagnosis of GIS. In this study, dielectric barrier discharge was used to generate CF4 plasma and modify multiwalled carbon nanotubes (MWNTs). The nanotubes were plasma-treated at optimum discharge conditions under different treatment times (0.5, 1, 2, 5, 8, 10, and 12 min). Pristine and treated MWNTs were used as gas sensors to detect H2S and SO2. The effects of treatment time on gas sensitivity were analyzed. Results showed that the sensitivity, response, and recovery time of modified MWNTs to H2S were improved, but the recovery time of SO2 was almost unchanged. At 10 min treatment time, the MWNTs showed good stability and reproducibility with better gas sensing properties compared with the other nanotubes. Xiaoxing Zhang, Xiaoqing Wu, Bing Yang, and Hanyan Xiao Copyright © 2015 Xiaoxing Zhang et al. All rights reserved. Synergetic Effects of Mechanical Properties on Graphene Nanoplatelet and Multiwalled Carbon Nanotube Hybrids Reinforced Epoxy/Carbon Fiber Composites Tue, 26 May 2015 09:53:39 +0000 http://www.hindawi.com/journals/jnm/2015/838032/ Graphene nanoplatelets (GNPs) and carbon nanotubes (CNTs) are novel nanofillers possessing attractive characteristics, including robust compatibility with most polymers, high absolute strength, and cost effectiveness. In this study, an outstanding synergetic effect on the grapheme nanoplatelets (GNPs) and multiwalled carbon nanotubes (CNTs) hybrids were used to reinforce epoxy composite and epoxy/carbon fiber composite laminates to enhance their mechanical properties. The mechanical properties of CNTs/GNPs hybrids on a fixed weight fraction (1 wt%) with mixing different ratio reinforced epoxy nanocomposite, such as ultimate tensile strength and flexure properties, were investigated. The mechanical properties of epoxy/carbon fiber composite laminates containing different proportions of CNTs/GNPs hybrids (0.5, 1.0, 1.5 wt%) were increased over that of neat laminates. Consequently, significant improvement in the mechanical properties was attained for these epoxy resin composites and carbon fiber-reinforced epoxy composite laminates. Pin-Ning Wang, Tsung-Han Hsieh, Chin-Lung Chiang, and Ming-Yuan Shen Copyright © 2015 Pin-Ning Wang et al. All rights reserved. Fabrication of PANI/C-TiO2 Composite Nanotube Arrays Electrode for Supercapacitor Tue, 26 May 2015 09:33:56 +0000 http://www.hindawi.com/journals/jnm/2015/140596/ Polyaniline/carbon doped TiO2 composite nanotube arrays (PANI/C-TiO2 NTAs) have been prepared successfully by electrodepositing PANI in C-TiO2 NTAs which were prepared by directly annealing the as-anodized TiO2 NTAs under Ar atmosphere. The organic residual in the TiO2 NTAs during the process of anodization acts as carbon source and is carbonized in Ar atmosphere to manufacture the C-TiO2 NTAs. The specific capacitance of the PANI/C-TiO2 electrode is 120.8 mF cm−2 at a current density of 0.1 mA cm−2 and remains 104.3 mF cm−2 at a current density of 2 mA cm−2 with the calculated rate performance of 86.3%. After 5000 times of charge-discharge cycling at a current density of 0.2 mA cm−2, the specific capacitance retains 88.7% compared to the first cycle. All these outstanding performances of the as-prepared PANI/C-TiO2 NTAs indicate it will be a promising electrode for supercapacitor. Chengcheng Zhang, Changjian Peng, Biao Gao, Xiang Peng, Xuming Zhang, Jingyuan Tao, Jinhan Kong, and Jijiang Fu Copyright © 2015 Chengcheng Zhang et al. All rights reserved. Magnetic and Electrical Properties of Nitrogen-Doped Multiwall Carbon Nanotubes Fabricated by a Modified Chemical Vapor Deposition Method Tue, 26 May 2015 09:18:34 +0000 http://www.hindawi.com/journals/jnm/2015/587416/ Chemical vapor deposition (CVD) is a preferential method to fabricate carbon nanotubes (CNTs). Several changes have been proposed to obtain improved CNTs. In this work we have fabricated nitrogen-doped multiwall carbon nanotubes (N-MWCNTs) by means of a CVD which has been slightly modified. Such modification consists in changing the content of the by-product trap. Instead of acetone, we have half-filled the trap with an aqueous solution of NaCl (0–26.82 wt.%). Scanning electron microscope (SEM) characterization showed morphological changes depending upon concentration of NaCl included in the trap. Using high resolution transmission electron microscopy several shape changes on the catalyst nanoparticles were also observed. According to Raman spectroscopy results N-MWCNTs fabricated using pure distillate water exhibit better crystallinity. Resistivity measurements performed on different samples by physical properties measurement Evercool system (PPMS) showed metallic to semiconducting temperature dependent transitions when high content of NaCl is used. Results of magnetic properties show a ferromagnetic response to static magnetic fields and the coercive fields were very similar for all the studied cases. However, saturation magnetization is decreased if aqueous solution of NaCl is used in the trap. María Luisa García-Betancourt, Yadira Itzel Vega-Cantu, Sofía Magdalena Vega-Díaz, Aarón Morelos-Gómez, Mauricio Terrones, and Emilio Muñoz-Sandoval Copyright © 2015 María Luisa García-Betancourt et al. All rights reserved. Influence of Ammonium Zirconium Carbonate on Properties of Poly(vinyl alcohol)/Xylan Composite Films Tue, 26 May 2015 08:53:34 +0000 http://www.hindawi.com/journals/jnm/2015/810464/ A series of composite films were prepared using poly(vinyl alcohol) (PVA) and xylan as degradable raw materials under the addition of glycerol and ammonium zirconium carbonate (AZC). The influences of AZC on the mechanical properties, water-resisting properties, thermal stability, solubility (S), and water vapor permeability of PVA/xylan composite films were comparatively discussed. The results showed that AZC had a positive impact on improving the water resistance and mechanical properties of composite films especially for elongation at break (EAB). With increasing the AZC amounts from 0% to 15%, EAB increased rapidly from 18.5% to 218.0%, and the S values decrease from 11.64% to 8.64%. When the AZC amount reached 15%, the tensile strength still performed well (22.10 MPa). The great compatibility of components in composite films was also observed. Moreover, the addition of AZC had great influences on the thermal stability of composite films and the degradation in soil. Xiao-feng Chen, Jun-li Ren, and Ling Meng Copyright © 2015 Xiao-feng Chen et al. All rights reserved. N-Type Conductive Ultrananocrystalline Diamond Films Grown by Hot Filament CVD Tue, 26 May 2015 08:25:10 +0000 http://www.hindawi.com/journals/jnm/2015/527025/ We present the synthesis of ultrananocrystalline diamond (UNCD) films by application of hot filament chemical vapor deposition (HFCVD). We furthermore studied the different morphological, structural, and electrical properties. The grown films are fine grained with grain sizes between 4 and 7 nm. The UNCD films exhibit different electrical conductivities, dependent on grain boundary structure. We present different contact metallizations exhibiting ohmic contact behavior and good adhesion to the UNCD surface. The temperature dependence of the electrical conductivity is presented between −200 and 900°C. We furthermore present spectroscopic investigations of the films, supporting that the origin of the conductivity is the structure and volume of the grain boundary. Michael Mertens, Markus Mohr, Neda Wiora, Kai Brühne, and Hans-Jörg Fecht Copyright © 2015 Michael Mertens et al. All rights reserved. A Review of the Application and Performance of Carbon Nanotubes in Fuel Cells Tue, 26 May 2015 08:14:08 +0000 http://www.hindawi.com/journals/jnm/2015/560392/ The fuel cell has the nature of high energy conversion efficiency and low pollutant emission. Carbon nanotubes used for fuel cells can decrease the needs of noble metals which are used for catalyst and improve the performance of fuel cells. The application of carbon nanotubes in fuel cells is summarized and discussed. The following aspects are described in this paper: the method used to reduce the platinum, the effect of carbon nanotubes on the fuel cell, improving the performance of fuel cell catalysts, the interaction between catalyst and carbon nanotube support, and the synthetic conditions of carbon nanotube supported catalyst. We summarize some of the results of previous studies and raise expectations for the microscopic state study of carbon nanotubes in the future. Chong Luo, Hui Xie, Qin Wang, Geng Luo, and Chao Liu Copyright © 2015 Chong Luo et al. All rights reserved. Applications of Nanostructured Carbon Materials in Constructions: The State of the Art Tue, 26 May 2015 08:09:55 +0000 http://www.hindawi.com/journals/jnm/2015/807416/ The most recent studies on the applications of nanostructured carbon materials, including carbon nanotubes, carbon nanofibers, and graphene oxides, in constructions are presented. First, the preparation of nanostructured carbon/infrastructure material composites is summarized. This part is mainly focused on how the nanostructured carbon materials were mixed with cementitious or asphalt matrix to realize a good dispersion condition. Several methods, including high speed melting mixing, surface treatment, and aqueous solution with surfactants and sonication, were introduced. Second, the applications of the carbon nanostructured materials in constructions such as mechanical reinforcement, self-sensing detectors, self-heating element for deicing, and electromagnetic shielding component were systematically reviewed. This paper not only helps the readers understand the preparation process of the carbon nanostructured materials/infrastructure material composites but also sheds some light on the state-of-the-art applications of carbon nanostructured materials in constructions. Shu-Nan Lu, Ning Xie, Li-Chao Feng, and Jing Zhong Copyright © 2015 Shu-Nan Lu et al. All rights reserved. Dynamic Deposition of Nanocopper Film on the β-SiCp Surface by Magnetron Sputtering Mon, 25 May 2015 12:57:08 +0000 http://www.hindawi.com/journals/jnm/2015/810986/ The uniform nanocopper film was deposited on the surface of micron β-SiC particle by magnetron sputtering technology successfully. The surface morphology and phase constitution of the β-SiC particle with nanocopper film were analyzed and dynamic deposition behavior was investigated in detail. The concept of dynamic deposition was put forward to interpret formation mechanism of copper nanofilm on the surface of β-SiC particles. Hu Ming, Zhang Yunlong, Shan Lin, Tang Lili, Gao Jing, Ren Xiaoxue, and Ding Peiling Copyright © 2015 Hu Ming et al. All rights reserved. A Potential Solution to Minimally Invasive Device for Oral Surgery: Evaluation of Surgical Outcomes in Rat Mon, 25 May 2015 06:37:02 +0000 http://www.hindawi.com/journals/jnm/2015/481854/ The objective of the present research was to investigate the thermal injury in the brain after minimally invasive electrosurgery using instruments with copper-doped diamond-like carbon (DLC-Cu) surface coating. The surface morphologies of DLC-Cu thin films were characterized using scanning electron microscopy and atomic force microscopy. Three-dimensional brain models were reconstructed using magnetic resonance imaging to simulate the electrosurgical operation. In adult rats, a monopolar electrosurgical instrument coated with the DLC-Cu thin film was used to generate lesions in the brain. Animals were sacrificed for evaluations on postoperative days 0, 2, 7, and 28. Data indicated that the temperature decreased significantly when minimally invasive electrosurgical instruments with nanostructure DLC-Cu thin films were used and continued to decrease with increasing film thickness. On the other hand, the DLC-Cu-treated device created a relatively small thermal injury area and lateral thermal effect in the brain tissues. These results indicated that the DLC-Cu thin film minimized excessive thermal injury and uniformly distributed the temperature in the brain. Taken together, our study results suggest that the DLC-Cu film on copper electrode substrates is an effective means for improving the performance of electrosurgical instruments. Keng-Liang Ou, Li-Hsiang Lin, Hsi-Jen Chiang, Han-Yi Cheng, Shyuan-Yow Chen, and Chiung-Fang Huang Copyright © 2015 Keng-Liang Ou et al. All rights reserved. Electrospinning of Nanofibers and Their Applications for Energy Devices Mon, 25 May 2015 06:28:10 +0000 http://www.hindawi.com/journals/jnm/2015/140716/ With the depletion of fossil fuels and the increasing demand of energy for economic development, it is urgent to develop renewable energy technologies to sustain the economic growth. Electrospinning is a versatile and efficient fabrication method for one-dimensional (1D) nanostructured fibers of metals, metal oxides, hydrocarbons, composites, and so forth. The resulting nanofibers (NFs) with controllable diameters ranging from nanometer to micrometer scale possess unique properties such as a high surface-area-to-volume and aspect ratio, low density, and high pore volume. These properties make 1D nanomaterials more advantageous than conventional materials in energy harvesting, conversion, and storage devices. In this review, the key parameters for e-spinning are discussed and the properties of electrospun NFs and applications in solar cells, fuel cells, nanogenerators, hydrogen energy harvesting and storage, lithium-ion batteries, and supercapacitors are reviewed. The advantages and disadvantages of electrospinning and an outlook on the possible future directions are also discussed. Xiaomin Shi, Weiping Zhou, Delong Ma, Qian Ma, Denzel Bridges, Ying Ma, and Anming Hu Copyright © 2015 Xiaomin Shi et al. All rights reserved. Nature of the Interstitials in Titanium Dioxide and Their Impact on Transmission Coefficient: Ab Initio Calculations Thu, 21 May 2015 08:33:04 +0000 http://www.hindawi.com/journals/jnm/2015/574752/ The ab initio calculations about the properties of the interstitials doping in the rutile TiO2 and their impact on the transport coefficients are reported. As the doping of the Zr or Ti interstitials in the TiO2, the lattice Ti4+ ions acquire the excess electrons so reduced to the Ti3+ or Ti2+ ions. However, the Cu interstitials could not lose enough electrons to reduce the lattice Ti4+ ions. Furthermore, the Ti or Cu interstitials in the ZrO2 also are unable to promote the lattice Zr4+ ions to form the lattice Zr3+ or Zr2+ ions. The high transport coefficients are observed in the defected TiO2 with the Ti or Zr interstitials as the high concentration of the Ti3+ or Ti2+ ions. So, the Zr interstitials are the favorable choice for the extra-doping to improve the transport properties in the TiO2-based resistive random access memory. Lei Li, Changfu Xia, Wenshi Li, Aimin Ji, Canyan Zhu, Lijun Zhang, Ziou Wang, Jianfeng Yang, and Ling-Feng Mao Copyright © 2015 Lei Li et al. All rights reserved. Semiconductor Nanomaterials for Energy Conversion and Storage Thu, 21 May 2015 07:45:46 +0000 http://www.hindawi.com/journals/jnm/2015/624146/ Xiang Wu, Xijin Xu, Chuanfei Guo, and Chee Kiang Ivan Tan Copyright © 2015 Xiang Wu et al. All rights reserved. Properties and Photocatalytic Activity of β-Ga2O3 Nanorods under Simulated Solar Irradiation Wed, 20 May 2015 09:34:53 +0000 http://www.hindawi.com/journals/jnm/2015/191793/ β-Ga2O3 nanorods are prepared by hydrothermal method and characterized by X-ray diffraction, high-resolution transmission electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, and photoluminescence spectra. The results reveal that high crystallinity, monoclinic phase of β-Ga2O3 nanorods were prepared with a diameter of about 60 nm and length of 500 nm. Photoluminescence study indicates that the β-Ga2O3 nanorods exhibit a broad blue light emission at room temperature. The β-Ga2O3 nanorods displayed high photocatalytic activity under simulated solar irradiation; after 2 h irradiation, over 95% of methylene blue solution and over 90% of methyl orange solution were decolorized. Since this process does not require additional hydrogen peroxide and uses solar light, it can be developed as an economically feasible and environmentally friendly method to treat dye effluent. Yinzhen Wang, Ning Li, Pingping Duan, Xuwei Sun, Benli Chu, and Qinyu He Copyright © 2015 Yinzhen Wang et al. All rights reserved.