Journal of Nanomaterials The latest articles from Hindawi Publishing Corporation © 2015 , Hindawi Publishing Corporation . All rights reserved. Effect of Substrate Temperature on the Thermoelectric Properties of the Sb2Te3 Thin Films Deposition by Using Thermal Evaporation Method Thu, 02 Jul 2015 12:21:57 +0000 The antimony-telluride (Sb2Te3) thermoelectric thin films were prepared on SiO2/Si substrates by thermal evaporation method. The substrate temperature that ranged from room temperature to 150°C was adopted to deposit the Sb2Te3 thin films. The effects of substrate temperature on the microstructures and thermoelectric properties of the Sb2Te3 thin films were investigated. The crystal structure and surface morphology of the Sb2Te3 thin films were characterized by X-ray diffraction analyses and field emission scanning electron microscope observation. The RT-deposited Sb2Te3 thin films showed the amorphous phase. Te and Sb2Te3 phases were coexisted in the Sb2Te3-based thin films as the substrate temperature was higher than room temperature. The average grain sizes of the Sb2Te3-based thin films were 39 nm, 45 nm, 62 nm, 84 nm, and 108 nm, as the substrate temperatures were 50°C, 75°C, 100°C, 125°C, and 150°C, respectively. The Seebeck coefficients, electrical conductivity, and power factor were measured at room temperature; we had found that they were critically dependent on the substrate temperature. Jyun-Min Lin, Ying-Chung Chen, Cheng-Fu Yang, and Wei Chen Copyright © 2015 Jyun-Min Lin et al. All rights reserved. Surface Patterning of PEDOT:PSS by Photolithography for Organic Electronic Devices Thu, 02 Jul 2015 11:35:22 +0000 Along with the development of organic electronics, conductive polymer of PEDOT:PSS has been attracting more and more attention because they possess various novel electrical, optical, and mechanical properties, which render them useful in modern organic optoelectronic devices. Due to its organic nature, it is lightweight and can be fabricated into flexible devices. For better device processing and integrating, it is essential to tune their surface morphologies, and photolithography is the best choice at present. In this paper, current PEDOT:PSS patterning approaches using photolithography are reviewed, and some of our works are also briefly introduced. Appropriate photolithographic patterning process for PEDOT:PSS will enable its application in future organic electronics. Shihong Ouyang, Yingtao Xie, Dongping Wang, Dalong Zhu, Xin Xu, Te Tan, and Hon Hang Fong Copyright © 2015 Shihong Ouyang et al. All rights reserved. Cu(In,Ga)Se2 Thin Films Codoped with Sodium and Bismuth Ions for the Use in the Solar Cells Thu, 02 Jul 2015 11:27:42 +0000 The codoping effects of sodium and bismuth ions on the characteristics of Cu(In,Ga)Se2 films prepared via the solution process were investigated in this study. When sodium and bismuth ions were incorporated into Cu(In,Ga)Se2, the ratio of the intensity of (112) diffraction peak to that of (220/204) diffraction peak was greatly increased. The codoping process not only enlarged the sizes of the grains in the films but also resulted in densification of the films. The carrier concentration of Cu(In,Ga)Se2 was found to be effectively increased to cause a reduction in the resistivity of the films. The above phenomena were attributed to the densified microstructures of the films and a decrease in the amount of the donor-type defects. The leakage current of the solar cells was found to be also decreased via the codoping process. Owing to the improved electrical properties of Cu(In,Ga)Se2 films, the conversion efficiency of the fabricated solar cells was significantly enhanced. Fu-Shan Chen, Jen-Cheng Sung, Che-Yuan Yang, and Chung-Hsin Lu Copyright © 2015 Fu-Shan Chen et al. All rights reserved. Thermal Properties of Asphalt Mixtures Modified with Conductive Fillers Thu, 02 Jul 2015 08:02:39 +0000 This paper investigates the thermal properties of asphalt mixtures modified with conductive fillers used for snow melting and solar harvesting pavements. Two different mixing processes were adopted to mold asphalt mixtures, dry- and wet-mixing, and two conductive fillers were used in this study, graphite and carbon black. The thermal conductivity was compared to investigate the effects of asphalt mixture preparing methods, the quantity, and the distribution of conductive filler on thermal properties. The combination of conductive filler with carbon fiber in asphalt mixture was evaluated. Also, rheological properties of modified asphalt binders with conductive fillers were measured using dynamic shear rheometer and bending beam rheometer at grade-specific temperatures. Based on rheological testing, the conductive fillers improve rutting resistance and decrease thermal cracking resistance. Thermal testing indicated that graphite and carbon black improve the thermal properties of asphalt mixes and the combined conductive fillers are more effective than the single filler. Byong Chol Bai, Dae-Wook Park, Hai Viet Vo, Samer Dessouky, and Ji Sun Im Copyright © 2015 Byong Chol Bai et al. All rights reserved. In Vivo Osteogenesis of Vancomycin Loaded Nanohydroxyapatite/Collagen/Calcium Sulfate Composite for Treating Infectious Bone Defect Induced by Chronic Osteomyelitis Thu, 02 Jul 2015 06:06:05 +0000 A novel antibacterial bone graft substitute was developed to repair bone defects and to inhibit related infections simultaneously. This bone composite was prepared by introducing vancomycin (VCM) to nanohydroxyapatite/collagen/calcium sulphate hemihydrate (nHAC/CSH). XRD, SEM, and CCK-8 tests were used to characterize the structure and morphology and to investigate the adhesion and proliferation of murine osteoblastic MC3T3-E1 cell on VCM/nHAC/CSH composite. The effectiveness in restoring infectious bone defects was evaluated in vivo using a rabbit model of chronic osteomyelitis. Our in vivo results implied that the VCM/nHAC/CSH composite performed well both in antibacterial ability and in bone regeneration. This novel bone graft substitute should be very promising for the treatment of bone defect-related infection in orthopedic surgeries. Xiaojie Lian, Kezheng Mao, Xi Liu, Xiumei Wang, and Fuzhai Cui Copyright © 2015 Xiaojie Lian et al. All rights reserved. Titanium Carbide Nanocrystals Synthesized from a Metatitanic Acid-Sucrose Precursor via a Carbothermal Reduction Wed, 01 Jul 2015 12:03:36 +0000 A TiC powder is synthesized from a micron-sized mesoporous metatitanic acid-sucrose precursor (precursor M) by a carbothermal reduction process. Control specimens are also prepared using a nanosized TiO2-sucrose precursor (precursor T) with a higher cost. When synthesized at 1500°C for 2 h in flowing Ar, the characteristics of the synthesized TiC from precursor M are similar to those of the counterpart from precursor T in terms of the crystal size (58.5 versus 57.4 nm), oxygen content (0.22 wt% versus 0.25 wt%), and representative sizes of mesopores: approximately 2.5 and 19.7–25.0 nm in both specimens. The most salient differences of the two specimens are found in the TiC from precursor M demonstrating (i) a higher crystallinity based on the distinctive doublet peaks in the high-two-theta XRD regime and (ii) a lower specific surface area (79.4 versus 94.8 m2/g) with a smaller specific pore volume (0.1 versus 0.2 cm3/g) than the counterpart from precursor T. Hyunho Shin and Jun-Ho Eun Copyright © 2015 Hyunho Shin and Jun-Ho Eun. All rights reserved. Synthesis of Three-Dimensional Fe3O4/Graphene Aerogels for the Removal of Arsenic Ions from Water Wed, 01 Jul 2015 09:36:22 +0000 We report the synthesis of three-dimensional Fe3O4/graphene aerogels (GAs) and their application for the removal of arsenic (As) ions from water. The morphology and properties of Fe3O4/GAs have been characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and superconducting quantum inference device. The 3D nanostructure shows that iron oxide nanoparticles are decorated on graphene with an interconnected network structure. It is found that Fe3O4/GAs own a capacity of As(V) ions adsorption up to 40.048 mg/g due to their remarkable 3D structure and existence of magnetic Fe3O4 nanoparticles for separation. The adsorption isotherm matches well with the Langmuir model and kinetic analysis suggests that the adsorption process is pseudo-second-ordered. In addition to the excellent adsorption capability, Fe3O4/GAs can be easily and effectively separated from water, indicating potential applications in water treatment. Yan Ye, Da Yin, Bin Wang, and Qingwen Zhang Copyright © 2015 Yan Ye et al. All rights reserved. Suspension Synthesis of Surfactant-Free Cuprous Oxide Quantum Dots Wed, 01 Jul 2015 08:01:32 +0000 Suspension methods were used to synthesize surfactant-free Cu2O quantum dots (Cu2O-QDs) in high precursor concentrations using sodium hypophosphite as a reducing agent. Transmission electron microscopy (TEM) observations indicated that a large amount of Cu2O-QDs were synthesized with diameters ranging from 7 to 10 nm. We propose a mechanism where DMSO acts as a surface passivation agent, explaining the possible formation of Cu2O-QDs. Noticeably, the Cu2O-QDs exhibited high and stable catalytic activity for the reduction of rhodamine B. Dongzhi Lai, Tao Liu, Xinyun Gu, Ying Chen, Jin Niu, Lingmin Yi, and Wenxing Chen Copyright © 2015 Dongzhi Lai et al. All rights reserved. Synthesis of Inorganic Nanocomposites by Selective Introduction of Metal Complexes into a Self-Assembled Block Copolymer Template Wed, 01 Jul 2015 07:18:51 +0000 Inorganic nanocomposites have characteristic structures that feature expanded interfaces, quantum effects, and resistance to crack propagation. These structures are promising for the improvement of many materials including thermoelectric materials, photocatalysts, and structural materials. Precise control of the inorganic nanocomposites’ morphology, size, and chemical composition is very important for these applications. Here, we present a novel fabrication method to control the structures of inorganic nanocomposites by means of a self-assembled block copolymer template. Different metal complexes were selectively introduced into specific polymer blocks of the block copolymer, and subsequent removal of the block copolymer template by oxygen plasma treatment produced hexagonally packed porous structures. In contrast, calcination removal of the block copolymer template yielded nanocomposites consisting of metallic spheres in a matrix of a metal oxide. These results demonstrate that different nanostructures can be created by selective use of processes to remove the block copolymer templates. The simple process of first mixing block copolymers and magnetic nanomaterial precursors and then subsequently removing the block copolymer template enables structural control of magnetic nanomaterials, which will facilitate their applicability in patterned media, including next-generation perpendicular magnetic recording media. Hiroaki Wakayama and Hirotaka Yonekura Copyright © 2015 Hiroaki Wakayama and Hirotaka Yonekura. All rights reserved. The Effect of Annealing on Nanothick Indium Tin Oxide Transparent Conductive Films for Touch Sensors Wed, 01 Jul 2015 07:13:30 +0000 This study aims to discuss the sheet resistance of ultrathin indium tin oxide (ITO) transparent conductive films during the postannealing treatment. The thickness of the ultrathin ITO films is 20 nm. They are prepared on B270 glass substrates at room temperature by a direct-current pulsed magnetron sputtering system. Ultrathin ITO films with high sheet resistance are commonly used for touch panel applications. As the annealing temperature is increased, the structure of the ultrathin ITO film changes from amorphous to polycrystalline. The crystalline of ultrathin ITO films becomes stronger with an increase of annealing temperature, which further leads to the effect of enhanced Hall mobility. A postannealing treatment in an atmosphere can enhance the optical transmittance owing to the filling of oxygen vacancies, but the sheet resistance rises sharply. However, a higher annealing temperature, above 250°C, results in a decrease in the sheet resistance of ultrathin ITO films, because more Sn ions become an effective dopant. An optimum sheet resistance of 336 Ω/sqr was obtained for ultrathin ITO films at 400°C with an average optical transmittance of 86.8% for touch sensor applications. Shih-Hao Chan, Meng-Chi Li, Hung-Sen Wei, Sheng-Hui Chen, and Chien-Cheng Kuo Copyright © 2015 Shih-Hao Chan et al. All rights reserved. The Reliability Improvement of Cu Interconnection by the Control of Crystallized - Diffusion Barrier Wed, 01 Jul 2015 06:46:04 +0000 Ta/TaN bilayers have been deposited by a commercial self-ionized plasma (SIP) system. The microstructures of Ta/TaN bilayers have been systematically characterized by X-ray diffraction patterns and cross-sectional transmission electron microscopy. TaN films deposited by SIP system are amorphous. The crystalline behavior of Ta film can be controlled by the N concentration of underlying TaN film. On amorphous TaN film with low N concentration, overdeposited Ta film is the mixture of α- and β-phases with amorphous-like structure. Increasing the N concentration of amorphous TaN underlayer successfully leads upper Ta film to form pure α-phase. For the practical application, the electrical property and reliability of Cu interconnection structure have been investigated by utilizing various types of Ta/TaN diffusion barrier. The diffusion barrier fabricated by the combination of crystallized α-Ta and TaN with high N concentration efficiently reduces the KRc and improves the EM resistance of Cu interconnection structure. Wei-Lin Wang, Chia-Ti Wang, Wei-Chun Chen, Kuo-Tzu Peng, Ming-Hsin Yeh, Hsien-Chang Kuo, Hung-Ju Chien, Jen-Chi Chuang, and Tzung-Hua Ying Copyright © 2015 Wei-Lin Wang et al. All rights reserved. The Influence of Thermal Conditions on V2O5 Nanostructures Prepared by Sol-Gel Method Wed, 01 Jul 2015 06:45:53 +0000 This work presents the result of structure investigations of V2O5 nanorods grown from thin films and powders prepared by sol-gel method. To examine the best temperature of nanorods crystallization, thin films deposited by spin-coating method on quartz glass or silicon substrates and bulk xerogel powders were annealed at various temperatures ranging from 100°C to 600°C. The structure of the samples was characterized by X-ray diffraction method (XRD), scanning electron microscope (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and mass spectroscopy (MS). The rod-like structure of V2O5 was obtained at 600°C on both quartz glass and silicon substrates and also from the bulk xerogel. The growth process and the effect of annealing treatment on the nanostructure are briefly discussed. M. Prześniak-Welenc, M. Łapiński, T. Lewandowski, B. Kościelska, L. Wicikowski, and W. Sadowski Copyright © 2015 M. Prześniak-Welenc et al. All rights reserved. Mesoporous Silica-Supported Sulfonyldiamine Ligand for Microwave-Assisted Transfer Hydrogenation Wed, 01 Jul 2015 06:38:30 +0000 N-Sulfonyl-1,2-diamine ligands, derived from 1,2-diaminocyclohexane and 1,2-diaminopropane, were immobilized onto mesoporous SBA-15 silica. The SBA-15-supported sulfonyldiamine-Ru complex was prepared in situ under microwave heating at 60 W for 3 min. The prepared sulfonyldiamine-Ru complex was used as an efficient catalyst for the transfer hydrogenation of ketones to the corresponding secondary alcohols. The heterogeneous complex showed extremely high catalytic activity with 99% conversion rate under microwave heating condition. The complexes were regenerated by simple filtration and reused two times without significant loss of activity. Shaheen M. Sarkar, Md. Eaqub Ali, Md. Shaharul Islam, Md. Lutfor Rahman, S. S. Rashid, M. R. Karim, and Mashitah Mohd Yusoff Copyright © 2015 Shaheen M. Sarkar et al. All rights reserved. Spectral Monitoring CH/C2 Ratio of Methane Plasma for Growing Single-Layer Graphene on Cu Wed, 01 Jul 2015 06:15:03 +0000 Single-layer graphene was grown on copper at a low temperature of 600°C by plasma-assisted thermal chemical vapor deposition. Its growth mechanism was discussed with reference to the emission spectra of the plasma. The methane plasma produces the active species (Hx, CHx, and Cx) without the addition of flowing hydrogen, and the amounts of hydrogen-containing species can be controlled by varying the plasma power. The effective distance was found between the plasma initial stage and the deposition stage for the single-layer graphene synthesis. The results reveal that high-quality graphene can be synthesized using methane plasma at a suitable plasma power. Shih-Hao Chan, Shih-Fang Liao, Hung-Pin Chen, Hung-Sen Wei, Sheng-Hui Chen, Cheng-Chung Lee, and Chien-Cheng Kuo Copyright © 2015 Shih-Hao Chan et al. All rights reserved. Superior PSZ-SOD Gap-Fill Process Integration Using Ultra-Low Dispensation Amount in STI for 28 nm NAND Flash Memory and Beyond Mon, 29 Jun 2015 12:41:28 +0000 The gap-fill performance and process of perhydropolysilazane-based inorganic spin-on dielectric (PSZ-SOD) film in shallow trench isolation (STI) with the ultra-low dispensation amount of PSZ-SOD solution have been investigated in this study. A PSZ-SOD film process includes liner deposition, PSZ-SOD coating, and furnace curing. For liner deposition, hydrophilic property is required to improve the contact angle and gap-fill capability of PSZ-SOD coating. Prior to PSZ-SOD coating, the additional treatment on liner surface is beneficial for the fluidity of PSZ-SOD solution. The superior film thickness uniformity and gap-fill performance of PSZ-SOD film are achieved due to the improved fluidity of PSZ-SOD solution. Following that up, the low dispensation rate of PSZ-SOD solution leads to more PSZ-SOD filling in the trenches. After PSZ-SOD coating, high thermal curing process efficiently promotes PSZ-SOD film conversion into silicon oxide. Adequate conversion from PSZ-SOD into silicon oxide further increases the etching resistance inside the trenches. Integrating the above sequence of optimized factors, void-free gap-fill and well-controlled STI recess uniformity are achieved even when the PSZ-SOD solution dispensation volume is reduced 3 to 6 times compared with conventional condition for the 28 nm node NAND flash and beyond. Chun Chi Lai, Yi Wen Lu, Hung Ju Chien, and Tzung Hua Ying Copyright © 2015 Chun Chi Lai et al. All rights reserved. A Stable Carbon Nanotube Nanofluid for Latent Heat-Driven Volumetric Absorption Solar Heating Applications Mon, 29 Jun 2015 12:25:32 +0000 Recently, direct solar collection through the use of broadly absorbing nanoparticle suspensions (known as nanofluids) has been shown as a promising method to improve efficiencies in solar thermal devices. By utilizing a volatile base fluid, this concept could also be applied to the development of a direct absorption heat pipe for an evacuated tube solar collector. However, for this to happen or for any other light-induced vapor production applications, the nanofluid must remain stable over extended periods of time at high temperatures and throughout repetitive evaporation/condensation cycles. In this work, we report for the first time a nanofluid consisting of plasma-functionalized multiwalled carbon nanotubes (MWCNTs) suspended in denatured alcohol, which achieves this required stability. In addition, optical characterization of the nanofluid demonstrates that close to 100% of solar irradiation can be absorbed over a relatively small nanofluid thickness. Nathan Hordy, Delphine Rabilloud, Jean-Luc Meunier, and Sylvain Coulombe Copyright © 2015 Nathan Hordy et al. All rights reserved. The Efficient Apoptotic Induction of Paclitaxel-Loaded Poly(N-vinylpyrrolidone)-block-poly(ε-caprolactone) Nanoparticles in the In Vitro Study of Lung Cancer Cell Lines Mon, 29 Jun 2015 11:26:49 +0000 Paclitaxel (Ptx) has been established as one of the most important components of first line chemotherapy regimen in the treatment of lung cancer. However, the poor solubility of Ptx makes it employ Cremophor as a solvent, which greatly limits its application due to the severe adverse effect. Encapsulation of Ptx into nanoparticles substantially increases the solubility of Ptx, therefore eradicating the necessity of Cremophor involvement. Here we report on a simple way of preparing Ptx-loaded nanoparticles formed by amphiphilic poly(N-vinylpyrrolidone)-block-poly(ε-caprolactone) (PVP-b-PCL) copolymers. Ptx was incorporated into PVP-b-PCL nanoparticles with a high loading efficiency. In vitro release study shows that Ptx was released from the nanoparticles in a sustained manner. The following experiments including cell staining and cytotoxicity tests indicated that Ptx-NPs led to enhanced induction of apoptosis in non-small-cell lung cancer cell lines NCI-1975 and A549, which is achieved by regulating the expression of apoptosis related proteins. Therefore, data from this study offers an effective way of improving the anticancer efficiency of Ptx by a nanodrug delivery system with amphiphilic PVP-b-PCL as drug carriers. Donghui Zheng, Huiping Ye, Can Luo, Huae Xu, and Ling Meng Copyright © 2015 Donghui Zheng et al. All rights reserved. Correlation between the Photocatalytic Degradability of PAHs over Pt/TiO2-SiO2 in Water and Their Quantitative Molecular Structure Mon, 29 Jun 2015 06:09:19 +0000 The correlation between the photocatalytic degradability of polycyclic aromatic hydrocarbons (PAHs) over Pt/TiO2-SiO2 in water and their quantitative molecular structure was studied. Six PAHs, namely, naphthalene, fluorene, phenanthrene, pyrene, benzo[a]pyrene, and dibenzo[a,h]anthracene, were tested in Pt/TiO2-SiO2 suspension under UV irradiation. The results showed that the degradation efficiencies of the higher molecular weight PAHs were enhanced significantly in the presence of Pt/TiO2-SiO2, while the degradation efficiencies of the lower molecular weight PAHs were decreased in the presence of Pt/TiO2-SiO2. Both the photolysis and photocatalysis of all PAHs fit the pseudo-first-order equation very well, except FL. Quantitative analysis of molecular descriptors of energy of the highest occupied molecular orbital (), energy of the lowest unoccupied molecular orbital (), and the difference between and , GAP (), suggested that the GAP was significant for predicting a PAHs’ photocatalytic degradability. Through comparison against the maximum GAP (7.4529 eV) of PAHs (dibenzo[a,h]anthracene) that could be photocatalytically degraded and the minimum GAP (8.2086 eV) of PAHs (pyrene) that could not be photocatalytically degraded in this study, the photocatalytic degradability of 67 PAHs was predicted. The predictions were partly verified by experimental photocatalytic degradation of anthracene and Indeno[]pyrene. Zhao-hui Luo, Chuan-ling Wei, Nan-nan He, Zhi-guo Sun, Hui-xin Li, and Dan Chen Copyright © 2015 Zhao-hui Luo et al. All rights reserved. Facile Synthesis and Characterization of N-Doped TiO2 Photocatalyst and Its Visible-Light Activity for Photo-Oxidation of Ethylene Sun, 28 Jun 2015 12:00:01 +0000 A facile wet chemical method was adopted for preparing highly photoactive nitrogen doped TiO2 (N-TiO2) powders with visible responsive capability, which could be achieved by the hydrolysis of titanium isopropoxide (TTIP) in the ammonium hydroxide precursor solution in various concentrations and then calcined at different temperatures. The N-TiO2 powders were characterized, and the photocatalytic activity was evaluated for the photocatalytic oxidation of ethylene gas under visible light irradiation to optimize the synthesizing conditions of N-TiO2 catalyst. The N-TiO2 photocatalytic powders were calcined in a range of temperatures from 300 to 600°C and obviously found to have greater photocatalytic activities than commercial TiO2 P25. The strong absorption in the visible light region could be ascribed to good crystallization and adapted sinter temperature of as prepared sample. XPS test demonstrated that the N was doped into TiO2 lattice and made an interstitial formation (Ti-O-N), and N doping also retarded the phase transformation from anatase to rutile as well. The N-TiO2 catalyst prepared with 150 mL ammonium hydroxide added and calcined at 500°C showed the best photocatalytic activity. The experimental results also proved the enhanced photoactivity of N-TiO2 material depends on the synthesizing conditions. Yu-Hao Lin, Chih-Huang Weng, Arun Lal Srivastav, Yao-Tung Lin, and Jing-Hua Tzeng Copyright © 2015 Yu-Hao Lin et al. All rights reserved. Graphene Platelets as Morphology Tailoring Additive in Carbon Nanotube Transparent and Flexible Electrodes for Heating Applications Thu, 25 Jun 2015 11:06:27 +0000 Flexible and transparent electrodes were fabricated with spray coating technique from paints based on multiwalled carbon nanotubes with the addition of graphene platelets. The work presents the influence of graphene platelets on the paints rheology and layers morphology, which has a strong connection to the electrooptical parameters of the electrodes. The paints rheology affects the atomization during spray coating and later the leveling of the coating on the substrate. Both technological aspects shape the morphology of the electrode and the distribution of nanoparticles in the coating. All these factors influence the sheet resistance and roughness, which is linked to the optical transmission and absorbance. In our research the electrode was applied as a transparent and elastic heating element with 68% optical transmission at 550 nm wavelength and 8.4 kΩ/□ sheet resistance. The elastic heating element was tested with a thermal camera at the 3 diverse supply voltages −20, 30, and 60 VDC. The test successfully confirmed and supported our proposed uses of elaborated electrodes. Grzegorz Wroblewski, Konrad Kielbasinski, Tomasz Stapinski, Janusz Jaglarz, Konstanty Marszalek, Barbara Swatowska, Lucja Dybowska-Sarapuk, and Malgorzata Jakubowska Copyright © 2015 Grzegorz Wroblewski et al. All rights reserved. EG-Assisted Synthesis and Electrochemical Performance of Ultrathin Carbon-Coated LiMnPO4 Nanoplates as Cathodes in Lithium Ion Batteries Thu, 25 Jun 2015 08:57:03 +0000 Ultrathin carbon-coated LiMnPO4 (ULMP/C) nanoplates were prepared through an ethylene glycol- (EG-) assisted pyrolysis method. Different from most of LiMnPO4/C works, the obtained ULMP/C possessed relatively small particle size (less than 50 nm in thickness) and preferable carbon coating (~1 nm in thickness, 2 wt.%). As a reference, LiMnPO4/C (LMP/C) composites were also fabricated via the traditional hydrothermal method. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TG), galvanostatic charge-discharge, and cyclic voltammetry (CV) were performed to characterize the crystalline phase, morphology, structure, carbon content, and electrochemical behaviors of samples. The electrochemical performance of bare and carbon-coated LiMnPO4 was evaluated as cathodes in lithium ion batteries. As a result, the obtained ULMP/C nanoplates demonstrated much higher reversible capacities (110.9 mAh g−1 after 50 cycles at 0.1 C) and rate performances than pure LMP and LMP/C composites. This facile and efficient EG-assisted pyrolysis method can enlighten us on exploiting advanced routes to modify active materials with ultrathin and homogeneous carbon layers. Liwei Su, Yali Sha, Jingkang Jiang, Lianbang Wang, and Yuanhao Wang Copyright © 2015 Liwei Su et al. All rights reserved. Synthesis of Spherical Bi2WO6 Nanoparticles by a Hydrothermal Route and Their Photocatalytic Properties Thu, 25 Jun 2015 06:28:31 +0000 Spherical Bi2WO6 nanoparticles were synthesized by a hydrothermal route. SEM observation shows that the size of the particles ranges from 60 to 120 nm and the average particle size is ~85 nm. TEM investigation shows that the particles are made up of subgrains with size of 5–10 nm. The bandgap energy of the particles is measured to be 2.93 eV by ultraviolet-visible diffuse reflectance spectroscopy. RhB was chosen as the target pollutant to evaluate the photocatalytic activity of the particles under irradiation of simulated sunlight, revealing that they exhibit an obvious photocatalytic activity. The effects of ethanol, KI, and BQ on the photocatalytic efficiency of Bi2WO6 particles towards the RhB degradation were investigated. It is observed that ethanol has no effect on the photocatalytic degradation of RhB, whereas KI and BQ exhibit a substantial suppression of RhB degradation. No hydroxyl (•OH) is found, by the photoluminescence technique using terephthalic acid as a probe molecule, to be produced over the irradiated Bi2WO6 particles. Based on the experimental results, photoexcited hole (h+) and superoxide (•) are suggested to be the two main active species responsible for the dye degradation, while •OH plays a negligible role in the photocatalysis. B. Wang, H. Yang, T. Xian, L. J. Di, R. S. Li, and X. X. Wang Copyright © 2015 B. Wang et al. All rights reserved. Phytofabrication of Bioactive Molecules Encapsulated Metallic Silver Nanoparticles from Cucumis sativus L. and Its Enhanced Wound Healing Potential in Rat Model Wed, 24 Jun 2015 11:12:38 +0000 The present study describes a rapid method for synthesis of metallic silver nanoparticles using callus (CAgNPs) and leaf extracts (LEAgNPs) of Cucumis sativus and evaluation of its wound healing activity in rat model. The prepared silver nanoparticles showed a peak at 350 nm corresponding to the surface plasmon resonance band. The FTIR spectroscopy measurements showed the presence of the possible biomolecules. X-ray diffraction analysis confirmed the crystalline structure of the synthesized silver nanoparticles. TEM images showed the size of the synthesized CAgNPs with diameter ranged from 21 nm to 23 nm with polygonal shape whereas, in the case of LEAgNPs, spherical shape was noticed with an average size between 11 nm and 19 nm. The EDX results indicated the chemical composition at specific locations on synthesized nanoparticles. Furthermore the topical application of ointment prepared using synthesized AgNPs was found to show enhanced wound healing activity in Wistar albino rat model. By the 21st day, the ointment base containing 5% (w/w) of silver nanoparticles showed 100% potential wound healing activity than the standard drug as well as control bases. Results strongly showed that the ointment base containing LEAgNPs was found to be very effective in wound repair mechanism in the experimental rats. Perumal Venkatachalam, Palanivel Sangeetha, Natesan Geetha, and Shivendra Vikram Sahi Copyright © 2015 Perumal Venkatachalam et al. All rights reserved. The Comparative PDT Experiment of the Inactivation of HL60 on Modified TiO2 Nanoparticles Tue, 23 Jun 2015 12:41:29 +0000 Four samples of modified titanium dioxide (TiO2), Fe/TiO2 (2 wt%), Fe/TiO2 (5 wt%), and 5-ALA/TiO2, were experimented in photodynamic therapy (PDT) on leukemia cells HL60, performing promising photocatalytic inactivation effect. Fe/TiO2 and 5-ALA/TiO2 were synthesized in methods of precipitation and ultrasonic methods, respectively. X-ray diffraction spectra and UV-Vis spectra were studied for the samples’ crystalline phase and redshift of absorption peak. Further, FTIR spectra and Raman spectra were obtained to examine the combination of 5-aminolevulinic (5-ALA) and TiO2 nanoparticles. The toxicity of these four kinds of nanoparticles was studied through darkroom experiments. And based on the concentration which caused the same toxic effect (90%) on HL60, PDT experiments of TiO2, Fe/TiO2 (2%), Fe/TiO2 (5%), and ALA/TiO2 were done, resulting in the fact that the photokilling efficiency was 69.7%, 71.6%, 72%, and 80.6%, respectively. Scanning electron microscope (SEM) images of the samples were also taken to study the morphology of HL60 cells before and after PDT, resulting in the fact the activation of the modified TiO2 from PDT was the main cause of cell apoptosis. Kaiqi Lu, Qiyun He, Li Chen, Baoquan Ai, and Jianwen Xiong Copyright © 2015 Kaiqi Lu et al. All rights reserved. Vision-Augmented Molecular Dynamics Simulation of Nanoindentation Tue, 23 Jun 2015 11:02:21 +0000 We present a user-friendly vision-augmented technique to carry out atomic simulation using hand gestures. The system is novel in its concept as it enables the user to directly manipulate the atomic structures on the screen, in 3D space using hand gestures, allowing the exploration and visualisation of molecular interactions at different relative conformations. The hand gestures are used to pick and place atoms on the screen allowing thereby the ease of carrying out molecular dynamics simulation in a more efficient way. The end result is that users with limited expertise in developing molecular structures can now do so easily and intuitively by the use of body gestures to interact with the simulator to study the system in question. The proposed system was tested by simulating the crystal anisotropy of crystalline silicon during nanoindentation. A long-range (Screened bond order) Tersoff potential energy function was used during the simulation which revealed the value of hardness and elastic modulus being similar to what has been found previously from the experiments. We anticipate that our proposed system will open up new horizons to the current methods on how an MD simulation is designed and executed. Rajab Al-Sayegh and Charalampos Makatsoris Copyright © 2015 Rajab Al-Sayegh and Charalampos Makatsoris. All rights reserved. Nonlocal Theory to Analyse Nanotube Structures under Tension Mon, 22 Jun 2015 08:49:33 +0000 Because nanocomposites have found augmented use in many industries, the analytical solutions are required to be developed. This paper presents the development of a new analytical method for studying nanotube structures under tension using layer-wise and Eringen theories. Two opposite ends of tubes are subjected to normal forces. Nonlocal governing differential equations are derived and presented. The theoretical developments determine the effect of the geometric and nonlocal constitutive relations for single-walled nanotubes (SWNTs), double-walled nanotubes (DWNTs), and multiwalled nanotubes (MWNTs) under tension loading. It is observed that all displacement components increase with the increase in the nonlocal parameter. Hamidreza Yazdani Sarvestani and Ali Naghashpour Copyright © 2015 Hamidreza Yazdani Sarvestani and Ali Naghashpour. All rights reserved. WO3 Nanoplates Film: Formation and Photocatalytic Oxidation Studies Mon, 22 Jun 2015 08:45:45 +0000 High surface area of tungsten oxide (WO3) nanoplates films was prepared via simple electrochemical anodization technique by controlling the fluoride content (NH4F) in electrolyte. The design and development of WO3-based nanostructure assemblies have gained significant interest in order to maximize specific surface area for harvesting more photons to trigger photocatalytic oxidation reaction. This study aims to determine the optimum content of NH4F in forming WO3 nanoplates on W film with efficient photocatalytic oxidation reaction for organic dye degradation by utilizing our solar energy. The NH4F was found to influence the chemical dissolution and field-assisted dissolution rates, thus modifying the final morphological of WO3-based nanostructure assemblies film. It was found that 0.7 wt% of NH4F is the minimum amount to grow WO3 nanoplates film on W film. The photocatalysis oxidation experimental results showed that WO3 nanoplates film exhibited a maximum degradation of methyl orange dye (≈75%) under solar illumination for 5 hours. This behavior was attributed to the better charge carriers transportation and minimizes the recombination losses with specific surface area of nanoplates structure. Chin Wei Lai Copyright © 2015 Chin Wei Lai. All rights reserved. Characterization and Evaluation of the Improved Performance of Modified Reverse Osmosis Membranes by Incorporation of Various Organic Modifiers and SnO2 Nanoparticles Sun, 21 Jun 2015 11:50:01 +0000 Reverse osmosis (RO) membranes modified with nanoparticles of varied concentrations (0.001–0.1 wt.%) were developed via in situ interfacial polymerization (IP) of trimesoyl chloride (TMC) and m-phenylenediamine (MPD) on nanoporous polysulfone supports. The nanoparticles dispersed in the dense nodular polyamide on the polysulfone side. The effects of IP reaction time and loading on membrane separation performance were studied. The modified reverse osmosis membranes were characterized by scanning electron microscopy (SEM), X-ray diffractometer (XRD), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), contact angle measurement, and atomic force microscopy (AFM). The synthesized nanoparticles size varies between 10 and 30 nm. The results exhibited a smooth membrane surface and average surface roughness from 31 to 68 nm. Moreover, hydrophilicity was enhanced and contact angle decreased. The outcomes showed that an IP reaction time was essential to form a denser -polyamide layer for higher salt rejection, the developed reverse osmosis membranes with the incorporation of the nanoparticles were examined by measuring permeate fluxes and salt rejection, and the permeate flux increased from 26 to 43.4 L/m2·h, while salt rejection was high at 98% (2000 ppm NaCl solution at 225 psi (1.55 MPa), 25°C). Kh. M. AL-Sheetan, Mohammed Rafi Shaik, A. S. AL-Hobaib, and N. M. Alandis Copyright © 2015 Kh. M. AL-Sheetan et al. All rights reserved. Impact of Ion Irradiation upon Structure and Magnetic Properties of NANOPERM-Type Amorphous and Nanocrystalline Alloys Sun, 21 Jun 2015 10:36:02 +0000 Structural modifications and their impact upon magnetic properties are studied in amorphous and nanocrystalline NANOPERM-type 57Fe75Mo8Cu1B16 alloy. They are introduced by irradiation with 130 keV N+ ions to the total fluencies of up to 2.5 × 1017 ions/cm2 under different cooling conditions. Increased temperature during the irradiation triggers formation of nanocrystallites of bcc-Fe in those subsurface regions that are affected by bombarding ions. No crystallization occurs when good thermal contact between the irradiated sample and a sample holder is assured. Instead, structural rearrangement which favours development of magnetically active regions was determined by the local probe methods of Mössbauer spectrometry. Dipole magnetic interactions dominate in subsurface regions on that side of the ribbons which was exposed to ion irradiation. Nevertheless, structural modifications demonstrate themselves also via macroscopic magnetic parameters such as temperature dependence of magnetization, Curie temperature, and hysteresis loops. Impact of only the temperature itself to the observed effects is assessed by the help of samples that were subjected just to heat treatment, that is, without ion irradiation. Marcel Miglierini and Mariusz Hasiak Copyright © 2015 Marcel Miglierini and Mariusz Hasiak. All rights reserved. Halo Evolution of Hypereutectic Al-17.5Si Alloy Treated with High-Current Pulsed Electron Beam Thu, 18 Jun 2015 11:21:04 +0000 Halo evolution of an Al-17.5Si alloy surface after treatment with increasing pulse numbers of a high-current pulsed electron beam (HCPEB) was investigated. A halo is a ring microstructure resembling a bull’s eye. SEM results indicate that the nanocrystallization of halo induced by HCPEB treatment leads to gradual diffusion of the Si phase. Multiple pulses numbers cause the Si phase to be significantly refined and uniformly distributed. In addition, nanosilicon particles with a grain size of 30~100 nm were formed after HCPEB treatment, as shown by TEM observation. XRD results indicate that Si diffraction peaks broadened after HCPEB treatment. The microhardness tests demonstrate that the microhardness at the midpoint from the halo edge to center decreased sharply from 9770.7 MPa at 5 pulses to 2664.14 MPa at 25 pulses. The relative wear resistance of a 15-pulse sample is effectively improved by a factor of 6.5, exhibiting optimal wear resistance. L. Hu, B. Gao, J. K. Lv, S. C. Sun, Y. Hao, and G. F. Tu Copyright © 2015 L. Hu et al. All rights reserved.