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1.	Amin, Sidra, et al. (författare) MoSx-Co3O4 Nanocomposite for Selective Determination of Ascorbic Acid 2021 Ingår i: Journal of Nanoscience and Nanotechnology. - : AMER SCIENTIFIC PUBLISHERS. - 1533-4880 .- 1533-4899. ; 21:4, s. 2595-2603 Tidskriftsartikel (refereegranskat)abstract Designing a nanocomposite with sensitive and selective determination of ascorbic acid is challenging task. It is possible through the exploitation of attractive features of nanoscience and nanotechnology for the synthesis of nanostructured materials. Herein, we report the decoration of nanoparticle of MoSx on the surface of Co3O4 nanowires by hydrothermal method. The MoSx nanoparticles shared the large surface on the Co3O4 nanowires, thus it supported in the development enzyme free ascorbic acid sensor. Non-enzymatic sensor based on MoSx-Co3O4 composite was found very selective for the determination of ascorbic acid (AA) in phosphate buffer solution of pH 7.4. The MoSx-Co3O4 nanocomposite was used to modify the glassy carbon electrode to measure AA from variety of practical samples. The MoSx-Co3O4 nanocomposite was used to modify the glassy carbon electrode and it has shown the attractive analytical features such as a low working potential +0.3 V, linear range of concentration from 100-7000 mu M, low limit of detection 14 mu M, and low limit of quantification (LOQ) of 42 mu M. The developed sensor is highly selective and stable. Importantly, it was applied successfully for the practical applications such as detection of AA from grapefruit, tomato and lemon juice. The excellent electrochemical properties of fabricated MoSx-Co3O4 nanocomposite can be attributed to the increasing electro active surface area of MoSx. The presented nanocomposite is earth abundant, environment friendly and inexpensive and it holds promising features for the selective and sensitive determination of AA from practical applications. The nanocomposite can be capitalized into the wide range of biomedical applications.
2.	Andersson, Gabriella, et al. (författare) Anisotropy Tuning in Tetragonal FeCo Alloys 2010 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 10:9, s. 6186-6189 Tidskriftsartikel (refereegranskat)abstract We review our previous work on magnetocrystalline anisotropy tuning of superlattices based on tetragonally distorted FeCo-alloys. In addition we present new experimental results on the effect of changing the composition of the FeCo alloy. The discussion is based on the separation of the magnetocrystalline anisotropy into contributions from the interfaces and strain, as well as from the composition.
3.	Andersson, Mikael, 1988 (författare) Nanoparticle Magnetism: Superspin Glasses 2019 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 19:8, s. 4903-4910 Tidskriftsartikel (refereegranskat)abstract This article discusses the magnetic super-phase, which occurs in strongly interacting magnetic nanoparticle systems. The phase is a nanoparticle analog to the atomic magnetic spin glass phase and is therefore called a superspin glass. Experimental data for a dense maghemite nanoparticle compact is presented and it is shown that this system forms a superspin glass phase by undergoing a second order phase transition. Below its transition temperature the system exhibits non-equilibrium dynamical properties similar to those of atomic spin glasses. It was shown that it is possible to tune the transition temperature by choosing the size of the particles used to make the compact. By mixing two sizes of particles (9 and 11.5 nm) and making compacts of different relative concentration of these sizes it was shown that it is the average dipolar interaction which determines the transition temperature.
4.	Anttu, Nicklas, et al. (författare) Coupling of Light into Nanowire Arrays and Subsequent Absorption 2010 Ingår i: Journal of Nanoscience And Nanotechnology. - : American Scientific Publishers. - 1533-4899 .- 1533-4880. ; 10:11, s. 7183-7187 Konferensbidrag (refereegranskat)abstract We present a theoretical study of the absorption of light in periodic arrays of InP nanowires. The absorption in the array depends strongly on the diameter and the length of the nanowires, as well as the period of the array. Nanowires of a length of just 2 Am are able, after an appropriate choice for the other parameters, to absorb more than 90% of the incident energy of TE and TM polarized light, with photon energies almost all the way down to the band gap energy and an incidence angle up to 50 degree. This high total absorption arises from a good coupling of the incident light into the nanowire array at the top interface between air and the array and absorption inside the array before the light reaches the interface between the nanowires and the substrate. We find that for a given photon energy there exists a critical nanowire diameter above which a dramatic increase in the absorption occurs. The critical diameter decreases for increasing photon energies, and is directly related to the dispersion of waveguiding modes in single isolated nanowires. A characterization showed that the absorption characteristics of the nanowire arrays are very promising for photovoltaic applications.
5.	Battiston, S., et al. (författare) Influence of Al and Mg Addition on Thermoelectric Properties of Higher Manganese Silicides Obtained by Reactive Sintering 2017 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 17:3, s. 1668-1673 Tidskriftsartikel (refereegranskat)abstract Higher manganese silicides (HMS), represented by MnSix (x = 1.71-1.75), are promising p-type candidates for thermoelectric (TE) energy harvesting systems at intermediate temperature range. The materials are very attractive as they may replace lead based compounds due to their nontoxicity, low cost of starting materials, and high thermal and chemical stability. Dense pellets were obtained through fast reactive sintering by spark plasma sintering (SPS). The addition -or nanoinclusion, of Al and Mg permitted the figure of merit enhancement of the material obtained with this technique, reaching the highest value of 0.40 at 600 degrees C. Morphology, composition and crystal structure of the samples were characterized by electron microscopies, energy dispersive X-ray spectroscopy, and X-ray diffraction analyses, respectively.
6.	Bhatti, Adeel Liaquat, et al. (författare) An Efficient and Functional Fe3O4/Co3O4 Composite for Oxygen Evolution Reaction 2021 Ingår i: Journal of Nanoscience and Nanotechnology. - : AMER SCIENTIFIC PUBLISHERS. - 1533-4880 .- 1533-4899. ; 21:4, s. 2675-2680 Tidskriftsartikel (refereegranskat)abstract The design of efficient, stable, durable and noble metal free electro catalysts for oxygen evolution reaction (OER) are of immediate need, but very challenging task. In this study, iron induction into cobalt oxide (Co3O4) has resulted composite structure by wet chemical method. The iron impurity has brought an electronic disorder into Fe3O4/cobalt oxide composite thereby efficient oxygen evolution reaction is demonstrated. An addition of iron content into composite resulted the alternation of morphology from Nano rods to clusters of nanoparticles. The successive addition of iron into composite system reduced the onset potential of OER as compared to the pristine cobalt oxide. A Tafel slope of 80 mVdec(-1) indicates the favorable oxygen evolution reaction kinetics on the sample 4. An over-potential of 370 mV is required to reach a 10 mAcm(-2) current density which is acceptable for a nonprecious catalyst. The catalyst is highly durable and stable for 30 hours. Electrochemical impedance spectroscopy further provided a deeper insight on charge transfer resistance and sample 4 has low charge transfer resistance that supported the OER polarization curves. The sample 4 has more electrochemical active surface area of 393.5 cm(2). These obtained results are exciting and highlighting the importance of composite structure and leave a huge space for the future investigations on composite materials for energy related applications.
7.	Bhatti, Muhammad Ali, et al. (författare) TiO2/ZnO Nanocomposite Material for Efficient Degradation of Methylene Blue 2021 Ingår i: Journal of Nanoscience and Nanotechnology. - : AMER SCIENTIFIC PUBLISHERS. - 1533-4880 .- 1533-4899. ; 21:4, s. 2511-2519 Tidskriftsartikel (refereegranskat)abstract In this research work, we have produced a composite material consisting titanium dioxide (TiO2) and zinc oxide (ZnO) nanostructures via precipitation method. Scanning electron microscopy (SEM) study has shown the mixture of nanostructures consisting nanorods and nano flower. Energy dispersive spectroscopy (EDS) study has confirmed the presence of Ti, Zn and O as main elements in the composite. X-ray diffraction (XID) study has revealed that the successful presence of TiO2 and ZnO in the composite. The composite material exhibits small optical energy band gap which led to reduction of the charge recombination rate of electron-hole pairs. The band gap for the composite TiO2/ZnO samples namely 1, 2, 3 and 4 is 3.18, 3.00, 2.97 and 2.83 eV respectively. Small optical bandgap gives less relaxation time for the recombination of electron and hole pairs, thus favorable photodegradation is found. The degradation efficiency for the TiO2/ZnO samples for methylene blue in order of 55.03%, 75.7%, 85.14% and 90.08% is found for the samples 1, 2, 3 and 4 respectively. The proposed study of titanium dioxide addition into ZnO is facile and inexpensive for the development of efficient photocatalysts. This can be capitalized at large scale for the energy and environmental applications.
8.	Bora, Tanujjal, et al. (författare) Applications of nanotechnology in wastewater treatment-A review 2014 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 14:1, s. 613-626 Tidskriftsartikel (refereegranskat)abstract Water on Earth is a precious and finite resource, which is endlessly recycled in the water cycle. Water, whose physical, chemical, or biological properties have been altered due to the addition of contaminants such as organic/inorganic materials, pathogens, heavy metals or other toxins making it unsafe for the ecosystem, can be termed as wastewater. Various schemes have been adopted by industries across the world to treat wastewater prior to its release to the ecosystem, and several new concepts and technologies are fast replacing the traditional methods. This article briefly reviews the recent advances and application of nanotechnology for wastewater treatment. Nanomaterials typically have high reactivity and a high degree of functionalization, large specific surface area, size-dependent properties etc., which makes them suitable for applications in wastewater treatment and for water purification. In this article, the application of various nanomaterials such as metal nanoparticles, metal oxides, carbon compounds, zeolite, filtration membranes, etc., in the field of wastewater treatment is discussed.
9.	Bora, Tanujjal, et al. (författare) Plasmonic Photocatalyst Design : Metal-Semiconductor Junction Affecting Photocatalytic Efficiency 2019 Ingår i: Journal of Nanoscience and Nanotechnology. - : AMER SCIENTIFIC PUBLISHERS. - 1533-4880 .- 1533-4899. ; 19:1, s. 383-388 Tidskriftsartikel (refereegranskat)abstract Silver-zinc oxide nanorods (Ag-ZnO NRs) and gold-zinc oxide nanorods (Au-ZnO NRs) plasmonic photocatalysts were fabricated by the deposition of Ag and Au nanoparticles on ZnO NRs. The photocatalysts were studied with electron microscopy, energy dispersive spectroscopy (EDS), UV-vis optical absorption and photoluminescence spectroscopy. The effect of type of metals on the ZnO surface on its photocatalytic activity under ultra violet (UV) as well as visible light excitation are investigated and their contribution towards enhanced photo-generated charge separation in terms of the type of junction (Ohmic or Schottky) the metal forms with the semiconductor are explained.
10.	Carvalho, Alexandra T.G., et al. (författare) Electronic and optical properties of chlorinated silicon nanoparticles 2013 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 13:2, s. 1039-1042 Tidskriftsartikel (refereegranskat)abstract First-principles calculations are used to investigate the structure, electronic and optical properties of silicon nanocystals with chlorine-passivated surface. The nanocrystals considered were approximately spherical, with diameters between 1.5 and 3.0 nm. We show that the nanocrystals with chlorinated surface have a smaller bandgap, lower optical absorption threshold, and greater ionization energy and electron affinity than hydrogenated silicon nanocrystals of the same size
11.	Carvalho, Alexandra T.G., et al. (författare) Increased electronic coupling in silicon nanocrystal networks doped with F4-TCNQ 2013 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 13:2, s. 1035-1038 Tidskriftsartikel (refereegranskat)abstract The modification of the electronic structure of silicon nanocrystals using an organic dopant, 2,3,5,6- tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F 4-TCNQ), is investigated using first-principles calculations. It is shown that physisorbed F4-TCNQ molecules have the effect of oxidizing the nanocrystal, attracting the charge density towards the F 4-TCNQ-nanocrystal interface, and decreasing the excitation energy of the system. In periodic F4-TCNQ/nanocrystal superlattices, F 4-TCNQ is suggested to enhance exciton separation, and in the presence of free holes, to serve as a bridge for electron/hole transfer between adjacent nanocrystals.
12.	Coelho, Margarida, et al. (författare) Nanotechnology in automotive industry : research strategy and trends for the future – small objects, big impacts 2012 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 12:8, s. 6621-6630 Tidskriftsartikel (refereegranskat)abstract The goal of this paper is to emphasize and present briefly the nanotechnology science and its potential impact on the automotive industry in order to improve the production of recent models with an optimization of the safety performance and a reduction in the environmental impacts. Nanomaterials can be applied in car bodies as light weight constructions without compromising the stiffness and crashwortiness, which means less material and less fuel consumption. This paper outlines the progress of nanotechnology applications into the safety features of more recent vehicle models and fuel efficiency, but also emphasis the importance of sustainable development on the application of these technologies and life cycle analysis of the considered materials, in order to meet the society trends and customers demands to improve ecology, safety and comfort.
13.	Ding, Zong-Ling, et al. (författare) Effect of Electrodes on Geometric and Transport Properties of the Graphene-Based Nanomolecular Devices 2011 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 11:12, s. 10778-10781 Tidskriftsartikel (refereegranskat)abstract Graphene-based nanomolecular devices are formed by connecting one of the prototype molecular materials of graphene nanoribbons to two Au electrodes. The geometric structure and electronic properties are calculated by using density functional theory. Basing on the optimized structure and the electronic distributions, we obtain the transport properties of the devices by using the Green's functional method. It is found that that the geometry structures of the molecule and the transport properties are sensitive to the distance between source and drain electrodes. With increasing the distances, the curvature radius of the atomic plane is increased, and the deformation energy is decreased. The current versus voltage curves have almost same threshold voltage with different distances between the electrodes. The transmission probability, the density of states and the external bias voltage play important role in determining the transport properties of the molecular devices.
14.	Dispenza, Clelia, et al. (författare) Radiation-Engineered Functional Nanoparticles in Aqueous Systems 2015 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 15:5, s. 3445-3467 Forskningsöversikt (refereegranskat)abstract Controlled synthesis of nanoscalar and nanostructured materials enables the development of novel functional materials with fine-tuned optical, mechanical, electronic, magnetic, conductive and catalytic properties that are of use in numerous applications. These materials have also found their potential use in medicine as vehicles for drug delivery, in diagnostics or in combinations thereof. In principle, nanoparticles can be divided into two broad categories, organic and inorganic nanoparticles. For both types of nanoparticles there are numerous possible synthetic routes. Considering the large difference in nature of these materials and the elementary reactions involved in the synthetic routes, most manufacturing techniques are complex and only suitable for one type of particle. Interestingly, radiation chemistry, i.e., the use of ionizing radiation from radioisotopes and accelerators to induce nanomaterials or chemical changes in materials, has proven to be a versatile tool for controlled manufacturing of both organic and inorganic nanoparticles. The advantages of using radiation chemistry for this purpose are many, such as low energy consumption, minimal use of potentially harmful chemicals and simple production schemes. For medical applications one more advantage is that the material can be sterile as manufactured. Radiation-induced synthesis can be carried out in aqueous systems, which minimizes the use of organic solvents and the need for separation and purification of the final product. The radiation chemistry of water is well known, as are the various ways of fine-tuning the reactivity of the system towards a desired target by adding different solutes. This, in combination with the controllable and adjustable irradiation process parameters, makes the technique superior to most other chemical methods. In this review, we discuss the fundamentals of radiation chemistry and radiation-induced synthesis of nanoparticles in aqueous solutions. The impact of dose and dose rate as well as of controlled addition of various solutes on the final particle composition, size and size distribution are described in detail and discussed in terms of reaction mechanism and kinetics.
15.	Duan, Haiming, et al. (författare) Computational studies of small carbon and iron-carbon systems relevant to carbon nanotube growth 2008 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 8:11, s. 6170-6177 Tidskriftsartikel (refereegranskat)abstract Density functional theory (DFT) calculations show that dimers and longer carbon strings are more stable than individual atoms on Fe(111) surfaces. It is therefore necessary to consider the formation of these species on the metal surfaces and their effect on the mechanism of single-walled nanotube (SWNT) growth. The good agreement between the trends (energies and structures) obtained using DFT and those based on the Brenner and AIREBO models indicate that these analytic models provide adequate descriptions of the supported carbon systems needed for valid molecular dynamics simulations of SWNT growth. In contrast, the AIREBO model provides a better description of the relative energies for isolated carbon species, and this model is preferred over the Brenner potential when simulating SWNT growth in the absence of metal particles. However, the PM3 semiempirical model appears to provide an even better description for these systems and, given sufficient computer resources, direct dynamics methods based on this model may be preferred.
16.	Fan, Liangdong, 1985-, et al. (författare) Study of Ceria-Carbonate Nanocomposite Electrolytes for Low-Temperature Solid Oxide Fuel Cells 2012 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 12:6, s. 4941-4945 Tidskriftsartikel (refereegranskat)abstract Composite and nanocomposite samarium doped ceria-carbonates powders were prepared by solidstatereaction, citric acid-nitrate combustion and modified nanocomposite approaches and used aselectrolytes for low temperature solid oxide fuel cells. X-ray Diffraction, Scanning Electron Microscope,low-temperature Nitrogen Adsorption/desorption Experiments, Electrochemical ImpedanceSpectroscopy and fuel cell performance test were employed in characterization of these materials.All powders are nano-size particles with slight aggregation and carbonates are amorphous incomposites. Nanocomposite electrolyte exhibits much lower impedance resistance and higher ionicconductivity than those of the other electrolytes at lower temperature. Fuel cell using the electrolyteprepared by modified nanocomposite approach exhibits the best performance in the whole operationtemperature range and achieves a maximum power density of 839 mW cm−2 at 600 C withH2 as fuel. The excellent physical and electrochemical performances of nanocomposite electrolytemake it a promising candidate for low-temperature solid oxide fuel cells.
17.	Farrell, Leo, et al. (författare) Influence of varying porogen loads and different UV cures on low-kappa film characteristics 2011 Ingår i: Journal of Nanoscience and Nanotechnology. - 1533-4880 .- 1533-4899. ; 11:9, s. 8363-8367 Tidskriftsartikel (refereegranskat)
18.	Ferraz, Natalia, et al. (författare) Role of Alumina Nanoporosity in Acute Cell Response 2011 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 11:8, s. 6698-6704 Tidskriftsartikel (refereegranskat)abstract This work studied the effect of nanoporous alumina in acute cellular response in an in vivo model. Nanoporous alumina membranes, with pore size diameters of 20 and 200 nm, were fabricated by anodic oxidation of aluminium. The membranes were thereafter characterized in terms of pore size distribution and chemical composition. To evaluate acute inflammatory response, the membranes were implanted in the peritoneal cavity of mice. Cell recruitment to the implant site was determined by fluorescence activated cell sorting (FACS) analysis. Cell adhesion to material surfaces was studied in terms of cell number, type, and morphology using scanning electron microscopy (SEM) and immunocytochemical staining followed by fluorescence microscopy. The fabricated nanoporous alumina membranes were found to have narrow pore size distribution. The in vivo study showed that 200 nm alumina membranes induced stronger inflammatory response than 20 nm membranes. This was reflected by the number of implant-associated phagocytes and the number of cells recruited to the implantation site. Since both pore-size membranes possess similar chemical composition, we believe that the observed difference in cell recruitment and adhesion is an effect of the material nanotopography. Our results suggest that nanotopography can be used to subtly control the recruitment and adherence of phagocytic cells during the acute inflammatory response to alumina membranes.
19.	Fu, T., et al. (författare) Aqueous Synthesis and Fluorescence-Imaging Application of CdTe/ZnSe Core/Shell Quantum Dots with High Stability and Low Cytotoxicity 2010 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 10:3, s. 1741-1746 Tidskriftsartikel (refereegranskat)abstract CdTe/ZnSe core/shell quantum dots were directly synthesized in an aqueous condition by heating a mixed solution of ZnCl2, NaHSe and CdTe QDs in the presence of mercaptosuccinic acid as a stabilizer. By controlling the size and composition, the CdTe/ZnSe QDs with emission wavelength ranging from 540 to 630 nm, high quantum yield (44%) and narrow full width at half maximum (FWHM) could be obtained. Characterization results with HRTEM, XRD and EDX have shown that the synthesized CdTe/ZnSe ON have good monodispersity and a nice crystal structure, and exhibited better stability and less cytotoxicity as compared with CdTe QDs. Furthermore, luminescent QD-IgG bioprobes were produced to detect the breast cancer marker Her2 on the surface of fixed MCF-7 cancer cells for their optical imaging.
20.	Fu, Ying, 1964, et al. (författare) Wave packet transmission in a ZnO nanorod under the influence of repulsive/attractive scattering center 2004 Ingår i: Journal of Nanoscience and Nanotechnology. - : AMER SCIENTIFIC PUBLISHERS. - 1533-4880 .- 1533-4899 .- 0000-0000. ; 4:02-Jan, s. 91-93 Tidskriftsartikel (refereegranskat)abstract We study electron wave packet propagation and scattering in ZnO nanorods. By solving the time-dependent three-dimensional Schrodinger equation, we were able to describe propagation and dynamics of the scattering process of the wave packet by ionized impurities. Scattering behavior of the wave packet by an attractive/repulsive scattering center is clearly demonstrated.
21.	Gao, Zhan, et al. (författare) Electrochemical Characterization on SDC/Na2CO3 Nanocomposite Electrolyte for Low Temperature Solid Oxide Fuel Cells 2011 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 11:6, s. 5413-5417 Tidskriftsartikel (refereegranskat)abstract Our previous work has demonstrated that novel core-shell SDC/Na2CO3 nanocomposite electrolyte possesses great potential for the development of low temperature (300-600 degrees C) solid oxide fuel cells. This work further characterizes the nanocomposite SDC/Na2CO3 electrochemical properties and conduction mechanism. The microstructure of the nanocomposite sintered at different temperatures was analyzed through scanning electron microscope (SEM) and X-ray diffraction (XRD). The electrical and electrochemical properties were studied. Significant conductivity enhancement was observed in the H-2 atmosphere compared with that of air atmosphere. The ratiocination of proton conduction rather than electronic conduction has been proposed consequently based on the observation of fuel cell performance. The fuel cell performance with peak power density of 375 mW cm(-2) at 550 degrees C has been achieved. A.C. impedance for the fuel cell under open circuit voltage (OCV) conditions illustrates the electrode polarization process is predominant in rate determination.
22.	Ghassemali, Ehsan, et al. (författare) Microstructural Evolution in a Low Carbon Steel During Cold Rolling and Subsequent Annealing 2010 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 10:9, s. 6177-6181 Tidskriftsartikel (refereegranskat)abstract Cold rolling with subsequent annealing of lath martensite structure could lead to the formation of nanostructures in low carbon steels. In the present work, the microstructural evolution of a 0.13% C steel during this process was studied. The specimens were austenitized at 950 °C followed by quenching in ice-brine to get martensitic structure. The quenched samples were aged at 200 °C for 30 min. These specimens were cold rolled up to 90% reduction in thickness without any intermediate annealing and then annealed at the temperatures from 400 to 600 °C. Scanning and transmission electron microscopy and color metallography was used to investigate the microstructure. Microscopic investigations showed that a multiphase nanostructure composed of equiaxed ferrite grains with the mean grain size of about 188 nm and small blocks of tempered martensite can be achieved under annealing at 400 °C for 90 min. Formation of the nanostructure was discussed from the viewpoint of characteristics of the martensite starting structure. Fragmentation of martensite lathes in cold rolling stage play an important role on recrystallization at annealing stage to get the ultrafine structure.
23.	Ghassemali, Ehsan (författare) Nanoporous Titania-Coated Alumina Membranes: Sol–Gel Synthesis and Characterisation 2010 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 10:9, s. 6222- Tidskriftsartikel (refereegranskat)abstract In this work, nanoporous titania top layers were deposited by dip-coating process on microporous α-alumina substrates using the sol–gel process. The alumina substrates were synthesized by slip casting method using Taguchi optimising approach. The microporous substrate was then used to coat nanoporous titania layers by the sol–gel method. The thickness, pore size, structure and permeability of the membranes were characterised using SEM, XRD, STA and Hg-Porosimetry. The process conditions to achieve defect-free nanoporous titania layers with the average pore size of about 4 nm coated on the microporous alumina substrates with the average pore size of about 270 nm were determined.
24.	Hemmaragala, Nanjundaswamy M., et al. (författare) Interaction of beta-Amyloid Interactions with Peptide Functionalized Gold Nanoparticles 2012 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 12:3, s. 2179-2184 Tidskriftsartikel (refereegranskat)abstract The physicochemical properties of gold nanoparticles (GNPs) functionalized with peptides and N-methylated peptides were studied with respect to their interaction with beta-amyloid (1-42). Peptides with sequences of CGGIGLMVG and CGGGGGIGLMVG linked with GNPs of an average diameter of 13 nm were employed for this study. The peptide-GNPs were found to be soluble and dispersed at pH 7.4 in a sodium phosphate aqueous buffer solution. The resonance spectra of each peptide coated GNP was measured in the absence and presence of beta-amyloid (1-42). The difference in the intensity of the lambda(max) of the resonance absorption bands was attributed to the interaction of the functionalized GNPs with the protein. Particles bearing the CGGGGGIGLMVG sequence exhibited the largest change in lambda(max) intensity; the prevention of fibril formation and inhibition of cytotoxicity was also examined.
25.	Ibupoto, Zafar Hussain, et al. (författare) A Potentiometric Biosensor for the Detection of Notch 3 Using Functionalized ZnO Nanorods 2014 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 14:9, s. 6704-6710 Tidskriftsartikel (refereegranskat)abstract The notch signalling plays a vital and radical role for the activity of cellular proliferation, differentiation and apoptosis. In this study, for the first time a particular biosensor is developed for the detection of notch 3. ZnO nanorods were fabricated on the gold coated glass substrate by hydrothermal method and afterwards were decorated with the gold nanoparticles by electrodepositing technique. Scanning electron microscopy (SEM) has shown the perpendicular to the substrate growth pattern of ZnO nanorods. X-ray diffraction (XRD) studies showed the c-axis oriented growth direction with wurtzite crystal structure of ZnO nanorods. X-ray Photoelectron Spectroscopy (XPS) and energy dispersive X-ray (EDX) techniques have shown the presence of Zn, O and Au atoms in the prepared functional material. Furthermore, the anti-notch 3 was physically adsorbed on the gold nanoparticles functionalized ZnO nanorods. The developed potentiometric immunosensor has shown response to the wide range of notch 3 molecules. The detected range included 1.00 x 10(-5)-1.50 x 10(0) mu g/mL with a sensitivity of 23.15 +/- 0.31 mV/decade. The analytical parameters including reproducibility, stability, and selectivity were also investigated and the observed results indicate the acceptable performance of the notch 3 biosensor. Moreover, the proposed notch 3 biosensor exhibited a fast response time of 10 s.
26.	Ibupoto, Zafar Hussain, et al. (författare) Development of a pH Sensor Using Nanoporous Nanostructures of NiO 2014 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 14:9, s. 6699-6703 Tidskriftsartikel (refereegranskat)abstract Glass is the conventional material used in pH electrodes to monitor pH in various applications. However, the glass-based pH electrode has some limitations for particular applications. The glass sensor is limited in the use of in vivo biomedical, clinical or food applications because of the brittleness of glass, its large size, the difficulty in measuring small volumes and the absence of deformation (inflexibility). Nanostructure-based pH sensors are very sensitive, reliable, fast and applicable towards in vivo measurements. In this study, nanoporous NiO nanostructures are synthesized on a gold-coated glass substrate by a hydrothermal route using poly(vinyl alcohol) (PVA) as a stabilizer. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques were used for the morphological and crystalline studies. The grown NiO nanostructures are uniform and dense, and they possess good crystallinity. A pH sensor based on these NiO nanostructures was developed by testing the different pH values from 2-12 of phosphate buffered saline solution. The proposed pH sensor showed robust sensitivity of -43.74 +/- 0.80 mV/pH and a quick response time of less than 10 s. Moreover, the repeatability, reproducibility and stability of the presented pH sensor were also studied.
27.	Ibupoto, Zafar Hussain, et al. (författare) Hydrothermal Growth of CuO Nanoleaf Structures, and Their Mercuric Ion Detection Application 2014 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 14:9, s. 6711-6717 Tidskriftsartikel (refereegranskat)abstract Mercury is the hazardous heavy metal ion for the environment and the humanbeing therefore its determination is very important and herein we describe the development of mercury ion sensor on the CuO nanoleaf like nanostructures using cetyltrimethylammonium bromide (CTAB) surfactant as template for the growth by hydrothermal growth method. Scanning electron microscopy and X-ray diffraction study has shown high density and good crystal quality of the fabricated CuO nanostructures respectively. The presented mercury ion sensor has detected the wide range of 1.0 x 10(-7) to 1.0 x 10(-1) M mercury ion concentrations with an acceptable Nernstian behaviour and a sensitivity of 30.1 +/- 0.6 mV/decade. The proposed mercury ion sensor exhibited low detection limit of 1.0 x 10(-8) M and also a fast response time of less than 5 s. In addition, the presented mercury ion sensor has shown an excellent repeatability, reproducibility, stability and selectivity. Moreover, the mercury ion selective electrode based on CuO nanoleaves was tested as an indicator electrode in the potentiometric titration.
28.	Jayakumar, Onattu Damodharan, et al. (författare) Room Temperature Ferromagnetism in Ce1-xFexO2-delta (x=0.0, 0.05, 0.10, 0.15 and 0.20) Nanoparticles Synthesised by Combustion Method 2010 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 10:4, s. 2299-2303 Tidskriftsartikel (refereegranskat)abstract Nanocrystalline Ce1-xFexO2-delta particles with different Fe concentrations (x = 0.0, 0.05, 0.10, 0.15, and 0.20) have been prepared by a gel-combustion method. X-ray diffraction data revealed the formation of an impurity free Ce1-xFexO2-delta products up to x = 0.15. This observation is further confirmed from the detailed studies conducted on 10 at.% Fe doped CeO2 using High-Resolution Transmission Electron Microscopy (HRTEM) imaging, Selected-Area Electron Diffraction (SAED) and Raman spectroscopy. DC magnetization studies as a function of field and temperature indicate that they are ferromagnetic with Curie temperature (T-c) well above room temperature.
29.	Jedrasik, Piotr, 1957, et al. (författare) Technological and Material Related Challenges for Large Area, High Aspect-Ratio, Near Teradot/Inch(2) Areal Density and Three-Dimensional Structuring of Polyaniline 2011 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 11:10, s. 8924-8935 Tidskriftsartikel (refereegranskat)abstract In this manuscript we report on a newly developed technology for the nanoscale processing of the conducting polyaniline (PANI) with an unprecedented areal patterning order and density control exceeding 0.25 teradot/inch(2). High resolution electron beam lithography was used to generate ordered 2D and 3D templates. A novel type of resist and dose-modulated 3D-electron beam lithography (RDM-3D-EBL), extensively exploiting the intrinsic properties of resist-electron beam interaction is detailed. Surface initiated and template confined aniline polymerization, through catalytic activity of metallic platinum, was then exploited to provide a genuine method for controlled nanoscale processing of polyaniline, a prototypical conjugated polymer that definitively settled the concept of synthetic metals. Using nanoscale polymerization reactors, ultimate resolution patterning and processing control of single polyaniline nanostructures was feasible. Aspects of the nanoscale polyaniline growth mechanism are discussed and the highly controllable, sub-picogram scale fabrication is emphasized. Near teradot/inch(2) pattern transfer technology, complex 3D structuring and physico-chemical functionalization of polyaniline can be subsequently harnessed to build a large variety of architectures with potential for emerging optoelectronic technologies. The method is scalable, can be applied on virtually any type of flexible or rigid substrates and provides a generic approach for nanopatterning surfaces with functional polymers. Technological and material related fabrication challenges are detailed and discussed.
30.	Jing, Yifu, et al. (författare) Synthesis and electrochemical performances of linicuzn oxides as anode and cathode catalyst for low temperature solid oxide fuel cell 2012 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 12:6, s. 5102-5105 Tidskriftsartikel (refereegranskat)abstract Low temperature solid oxide fuel cell (LTSOFC, 300-600 Â°C) is developed with advantages compared to conventional SOFC (800-1000 Â°C). The electrodes with good catalytic activity, high electronic and ionic conductivity are required to achieve high power output. In this work, a LiNiCuZn oxides as anode and cathode catalyst is prepared by slurry method. The structure and morphology of the prepared LiNiCuZn oxides are characterized by X-ray diffraction and field emission scanning electron microscopy. The LiNiCuZn oxides prepared by slurry method are nano Li 0.28Ni 0.72O, ZnO and CuO compound. The nano-crystallites are congregated to form ball-shape particles with diameter of 800-1000 nm. The LiNiCuZn oxides electrodes exhibits high ion conductivity and low polarization resistance to hydrogen oxidation reaction and oxygen reduction reaction at low temperature. The LTSOFC using the LiNiCuZn oxides electrodes demonstrates good cell performance of 1000 mW cm -2 when it operates at 470 Â°C. It is considered that nano-composite would be an effective way to develop catalyst for LTSOFC.
31.	Jönsson, Petra E. (författare) Effects of Interparticle Interaction in Ferromagnetic Nanoparticle Systems 2010 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 10:9, s. 6067-6071 Tidskriftsartikel (refereegranskat)abstract The effect of interparticle interaction in ferromagnetic nanoparticle systems is reviewed focusing on metallic nanoparticles in an insulating host. Strong dipolar interparticle interactions may give rise to a superspin glass phase with dynamical properties radically different from the superparamagnetic relaxation displayed by non-interacting or only weakly interacting nanoparticles. Strong exchange coupling in nanoparticle systems with a volume concentration above the threshold for geometrical percolation induces ferromagnetism.
32.	Kamara, S., et al. (författare) In-Plane Magnetic Anisotropy and Temperature Dependence of Switching Field in (Ga, Mn)As Ferromagnetic Semiconductors 2012 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 12:6, s. 4868-4873 Tidskriftsartikel (refereegranskat)abstract We explore the magnetic anisotropy of GaMnAs ferromagnetic semiconductor by Planar Hall Effect (PHE) measurements. Using low magnitude of applied magnetic field (i.e., when the magnitude H is smaller than both cubic Hc and uniaxial Hu anisotropy field), we have observed various shapes of applied magnetic field direction dependence of Planar Hall Resistance (PHR). In particular, in two regions of temperature. At T TC/2 the “zigzag-shape” signal of PHR. They reflect different magnetic anisotropy and provide information about magnetization reversal process in GaMnAs ferromagnetic semiconductor. The theoretical model calculation of PHR based on the free energy density reproduces well the experimental data. We report also the temperature dependence of anisotropy constants and magnetization orientations. The transition of easy axis from biaxial to uniaxiale axes has been observed and confirmed by SQUID measurements.
33.	Kapaklis, Vassilios, 1978-, et al. (författare) Nanolithographic Templates Using Diblock Copolymer Films on Chemically Heterogeneous Substrates 2010 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 10:9, s. 6056-6061 Tidskriftsartikel (refereegranskat)abstract The orientation of the lamellae formed by the phase separation of symmetric diblock copolymer thin films is strongly affected by the wetting properties of the polymer blocks with respect to the substrate. On bare silicon wafers the lamellae of polystyrene-b-polymethylmethacrylate thin films tend to order parallel to the wafer surface, with the polymethylmethacrylate block preferentially wetting silicon. We have developed a methodology for inducing the arrangement of lamellae perpendicular to the substrate by using chemically modified substrates. This is done by chemisorbing a self-assembled monolayer of thiol-terminated alkane chains on thin gold films deposited on silicon wafers. We also show that it is possible to spatially control the perpendicular orientation of the lamellae at sub-micron length scales by using simple chemical patterns and etch them, in order to produce nanolithographic templates. This method may be of great technological interest for the preparation of well-defined templates using block copolymer thin films.
34.	Kapaklis, Vassilios, 1978-, et al. (författare) Structure and Magnetic Properties of hcp and fcc Nanocrystalline Thin Ni Films and Nanoparticles Produced by Radio Frequency Magnetron Sputtering 2010 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 10:9, s. 6024-6028 Tidskriftsartikel (refereegranskat)abstract We report on the growth of thin Ni films by radio frequency magnetron sputtering in Ar-plasma. The growth temperature was about 350 K and the films were deposited on various substrates such as glass, silicon, sapphire and alumina. The thickness of the thinnest films was estimated by the appearance of Kiessig fringes up to about 2 theta = 8 degrees in the small-angle X-ray diffraction pattern, as expected for high-quality atomically-flat thin films. With the help of this, a quartz balance system was calibrated and used for measuring the thickness of thicker samples with an accuracy of better than 5%. Structural characterization via X-ray diffraction and high resolution transmission electron microscopy revealed an Ar-gas pressure window, where single phase hcp Ni films may be grown. The magnetic response of the Ni films was checked at room temperature via a newly established and fully automatic polar magneto-optic Kerr effect magnetometer. The hcp films show no magnetic response. Interestingly, the magnetic saturation field of fcc films deposited at low Ar pressure is comparable to the one of bulk Ni, while the one of fcc films deposited at high Ar pressures is decreased, revealing the presence of residual strain in the films. Finally, it is shown that it is possible to form films which contain magnetic Ni fcc nanoparticles in a non-magnetic hcp matrix, i.e., a system interesting for technological applications demanding a single Ni target for its production.
35.	Karimipour, Masoud, et al. (författare) Effect of Annealing Temperature on the Structural and Magnetic Properties of Co-Doped TiO2 Nanoparticles via Complex-Polymer Sol-Gel Method 2012 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 12:2, s. 950-954 Tidskriftsartikel (refereegranskat)abstract Co-doped TiO2 nanoparticles were synthesized via non hydrous complex-polymer sol gel method. A series of Co-x:Ti1-xO2 samples with x = 0.01, 0.03, 0.05, 0.08 and 0.10, were prepared and subsequently annealed at 400 degrees, 600 degrees and 800 degrees C. Structural and magnetic properties of Co-x:Ti1-xO2 have been studied by means of X-ray diffraction and DC magnetometry. All samples annealed at 400 degrees C show a paramagnetic behavior with an average grain size of 11 nm. With increasing annealing temperatures a complete crystallization is seen with growth of the cluster size up to 31 nm with clear evidence of a presence of CoTiO3. For all concentrations and annealing conditions no sign of a metallic phase, even at x = 0.10, is seen.
36.	Khokhar, Shams Parveen, et al. (författare) An Efficient Nickel Sulfide@NiO Nanocomposite Catalyst with High Density of Active Sites for the Hydrogen Evolution Reaction in Alkaline Media 2021 Ingår i: Journal of Nanoscience and Nanotechnology. - : AMER SCIENTIFIC PUBLISHERS. - 1533-4880 .- 1533-4899. ; 21:4, s. 2520-2528 Tidskriftsartikel (refereegranskat)abstract Efficient hydrogen evolution reaction (HER) catalysts based on the earth-abundant materials are highly vital to design practical and environmentally friendly water splitting devices. In this study, we present an optimized strategy for the development of active catalysts for hydrogen evolution reaction HER. The composite catalysts are prepared with the nanosurface of NiO for the deposition of NiS by hydrothermal method. In alkaline electrolyte, the NIS/NiO nanocomposite has shown excellent catalytic HER properties at the low onset potential and small Tafel slope of 72 mV dec(-1). A current density of 10 mA/cm(2) is achieved by the nanocomposite obtained with 0.4 gram of NiO as nanosurface for the deposition of NiS (sample 4) at the cost of 429 mV versus RHE. The sample 4 carries more active sites that allow it to act as excellent HER catalyst. Based on this study, we conclude that increasing the nickel oxide content into composite sample facilitates the HER process. Additionally, a long term HER stability for 10 hours and good durability is also demonstrated by the sample 4. Our findings reveal that the optimization of nickel oxide content in the preparation of catalyst leads to the excellent HER activity for the design of practical water splitting devices and other related applications.
37.	Khun, Kimleang, et al. (författare) A Selective Potentiometric Copper (II) Ion Sensor Based on the Functionalized ZnO Nanorods 2014 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 14:9, s. 6723-6731 Tidskriftsartikel (refereegranskat)abstract In this work, ZnO nanorods were hydrothermally grown on the gold-coated glass substrate and characterized by field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) techniques. The ZnO nanorods were functionalized by two different approaches and performance of the sensor electrode was monitored. Fourier transform infrared spectroscopy (FTIR) was carried out for the confirmation of interaction between the ionophore molecules and ZnO nanorods. In addition to this, the surface of the electrode was characterized by X-ray photoelectron spectroscopy (XPS) showing the chemical and electronic state of the ionophore and ZnO nanorod components. The ionophore solution was prepared in the stabilizer, poly vinyl chloride (PVC) and additives, and then functionalized on the ZnO nanorods that have shown the Nernstian response with the slope of 31 mV/decade. However, the Cu2+ ion sensor was fabricated only by immobilizing the selective copper ion ionophore membrane without the use of PVC, plasticizers, additives and stabilizers and the sensor electrode showed a linear potentiometric response with a slope of 56.4 mV/decade within a large dynamic concentration range (from 1.0 x 10(-6) to 1.0 x 10(-1) M) of copper (II) nitrate solutions. The sensor showed excellent repeatability and reproducibility with response time of less than 10 s. The negligible response to potentially interfering metal ions such as calcium (Ca2+), magnesium (Mg2+), potassium (K+), iron (Fe3+), zinc (Zn2+), and sodium (Na+) allows this sensor to be used in biological studies. It may also be used as an indicator electrode in the potentiometric titration.
38.	Khun, Kimleang, et al. (författare) An Electrochemical Dopamine Sensor Based on the ZnO/CuO Nanohybrid Structures 2014 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 14:9, s. 6646-6652 Tidskriftsartikel (refereegranskat)abstract The selective detection of dopamine (DA) is of great importance in the modern medicine because dopamine is one of the main regulators in human behaviour. In this study, ZnO/CuO nanohybrid structures, grown on the gold coated glass substrate, have been investigated as a novel electrode material for the electrochemical detection of dopamine. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques were used for the material characterization and the obtained results are in good agreement. The selective determination of dopamine was demonstrated by cyclic voltammetry (CV) and amperometric experiments. The amperometric response was linear for dopamine concentrations between 1.0 x 10(-3) and 8.0 mM with a sensitivity of 90.9 mu A mM(-1) cm(-2). The proposed dopamine biosensor is very stable, selective over common interferents as glucose, uric acid and ascorbic acid, and also good reproducibility was observed for seven electrodes. Moreover, the dopamine sensor exhibited a fast response time of less than 10 s. The wide range and acceptable sensitivity of the presented dopamine sensor provide the possible application in analysing the dopamine from the real samples.
39.	Kukli, Kaupo, et al. (författare) Atomic Layer Deposition of Ruthenium Films on Strontium Titanate 2011 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 11:9, s. 8378-8382 Tidskriftsartikel (refereegranskat)abstract Atomic layer deposition of ruthenium on SrTiO(3) layers was investigated using (C(2)H(5)C(5)H(4)) center dot (NC(4)H(4))Ru and air as precursors. For comparison, the growth was studied also on ZrO(2) films and SiO(2)/Si surfaces. Deposition temperature was 325 degrees C. Using rather short but intense air pulses, smooth and uniform Ru films were deposited on SrTiO(3). The films were crystallized at early stages of the growth. The nucleation density and rate on SrTiO(3) were notably lower compared to that on ZrO(2) and SiO(2), but the physical qualities including the film conductivity were considerably enhanced after reaching Ru film thickness around 10 nm.
40.	Kurtan, U., et al. (författare) Magnetically Recyclable Fe3O4@His@Cu Nanocatalyst for Degradation of Azo Dyes 2016 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 16:3, s. 2548-2556 Tidskriftsartikel (refereegranskat)abstract Fe3O4@His@Cu magnetic recyclable nanocatalyst (MRCs) was synthesized by reflux method using L-histidine as linker. The composition, structure and magnetic property of the product were characterized by X-ray powder diffraction (XRD), Scanning electron microscopy (SEM), Fourier Transform infrared spectroscopy (FT-IR) and vibrating sample magnetometry (VSM). Powder XRD, FTIR and EDAX results confirmed that the as-synthesized products has Fe3O4 with spinel structure and Cu nanoparticles with moderate crystallinity without any other impurities. The surface of the Fe3O4@His nanocomposite was covered by tiny Cu nanoparticles. We examine the catalytic activity of Fe3O4@His@Cu MRCs for the degradation of two azo dyes, methyl orange (MO) and methylene blue (MB) as well as their mixture. The reusability of the nanocatalyst was good and sustained even after 3 cycles. Therefore this innovated Fe3O4@His@Cu MRCs has a potential to be used for purification of waste water.
41.	Li, Junxin, et al. (författare) Rapid Acid-Mediated Purification of Single-Walled Carbon Nanotubes with Homogenization of Bulk Properties 2007 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 7:4-5, s. 1525-1529 Tidskriftsartikel (refereegranskat)abstract A rapid, mild and readily scaleable method for purification and isolation of single-walled nanotubes (SWNTs) using aqueous nitric acid that, in only 1-2 hours at reflux temperature, not only decrease the content of residual metal particles but also the relative ratio of small diameter and metallic NTs. The acid-treated SWNTs have been characterised by TEM, FT-IR, and Raman spectroscopy (514 and 783 cm-1). The results are discussed in relation to observations from other acid-mediated treatments and the reactive chemical species involved at different conditions.
42.	Li, Song, et al. (författare) Electrochemical Performances of Nanocomposite Solid Oxide Fuel Cells Using Nano-Size Material LaNi0.2Fe0.65Cu0.15O3 as Cathode 2009 Ingår i: Journal of Nanoscience and Nanotechnology. - 1533-4880 .- 1533-4899. ; 9:6, s. 3824-3827 Tidskriftsartikel (refereegranskat)abstract In order to develop nanocomposite solid oxide fuel cells (NANOCOFCs) at the range of intermediate temperature (500-700 degrees C), the new cathode materials LaNi0.2Fe0.8-xCuxO3 (x = 0.0-0-2) (LNFCu) powders were prepared using coprecipitation method. It was found that the orthorhombic structure could be formed after being calcined at 900 degrees C for 4 h, and the powders were mainly composed of nano-size particles. The lattice volume of LNFCu decreased with increasing x, and the second phase La2CuO4 appeared when x = 0.15. Fuel cells based on the nano-ceramic composite electrolyte were fabricated to evaluate the electrochemical properties of the LNFCu materials as cathodes at different operating temperatures. The peak power density of the fuel cell with LaFe0.65Ni0.2Cu0.15O3 cathode reached 635.2 mW/cm(2) and 762.7 mW/cm(2) at 580 degrees C and 650 degrees C respectively, which were much higher than that of LaFe0.8Ni0.2O3 under the same condition. The results indicate doping with copper improves evidently electrochemical properties of the cathode compared with the LaFe0.8Ni0.2O3 cathode. The excellent performance of fuel cells makes LaNi0.2Fe0.8-xCuxO3 material as the candidate electrode for NANOCOFCs.
43.	Li, Shanghua, et al. (författare) Novel Solution Route Synthesis of Low Thermal Conductivity Nanocrystalline Bismuth Telluride 2010 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 10:11, s. 7658-7662 Tidskriftsartikel (refereegranskat)abstract A novel synthesis approach based on a solution route has been developed for the fabrication of nanocrystalline bismuth telluride. The method consists of dissolving both bismuth and tellurium into the same organic solvent with the assistance of complexing agents and one-step coprecipitation of bismuth telluride. The synthesized nanocrystalline bismuth telluride powders possess rhombohedral crystal structure and are nanosheet/nanorod-like with an average size of between 30 and 40 nm. The thermal conductivity of the hot-pressed compact consolidated from the as-synthesized nanopowders is 0.39-0.45 Wm(-1)K(-1) in the temperature range of 323 to 523 K, which is at most one third of that of bulk bismuth telluride-based materials reported in the literature. Such low thermal conductivity of the investigated bismuth telluride is mainly attributed to substantially high concentration of grain boundaries provided by nanostructuring to scatter phonons intensively.
44.	Li, Shanghua, et al. (författare) Template electrodeposition of ordered bismuth telluride nanowire arrays 2009 Ingår i: Journal of Nanoscience and Nanotechnology. - 1533-4880 .- 1533-4899. ; 9:2, s. 1543-1547 Tidskriftsartikel (refereegranskat)abstract Thermoelectric bismuth telluride nanowire arrays have been synthesized by direct-current electrodeposition into porous anodic alumina membranes both galvanostatically and potentiostatically. The as-synthesized Bi2Te3 nanowire arrays are highly ordered in large area, stoichiometric, uniform, with high aspect ratio (above 100) and high filling ratio (>90%) of the membrane. The effects of different electrochemical deposition parameters on crystal structures, morphology and composition have been investigated. Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) have been used to characterize the physical and chemical properties of the nanowires.
45.	Lim, Eunhee, et al. (författare) Carbazole Functionalized Isocyanide Brushes in Heterojunction Photovoltaic Devices 2012 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 12:1, s. 503-507 Tidskriftsartikel (refereegranskat)abstract In this work, carbazole-containing polyisocyanide (PIACz) brushes were used for photovoltaic devices. A photovoltaic device was fabricated on top of the brushes by spin-coating a suitable acceptor and evaporating an Al cathode. Devices with a poly(N-vinylcarbazole) (PVK) bulk polymer were also prepared for comparison. Interestingly, the brushes showed better photovoltaic characteristics as compared to the blended PVK system. This is attributed to the specific morphologies of the polyisocyanide brushes, which provide a large interfacial area between the donor and acceptor for efficient photogeneration. It was found that the device performance varied according to the molecular size of the incorporated acceptors.
46.	Liu, Li-Hong, et al. (författare) Electrical Properties of Covalently Immobilized Single-Layer Graphene Devices 2011 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 11:2, s. 1288-1292 Tidskriftsartikel (refereegranskat)abstract Arrays of covalently immobilized and aligned graphene ribbons have been successfully prepared on silicon wafers. The effect of covalent modification on the electrical properties of the single-layer graphene was investigated. The effective electron field mobility of the constructed FETs, measured at 2700 cm(2)V(-1)s(-1), was higher than that for graphene film directly deposited on SiO(2), possibly due to lower phonon scattering from the substrate surface, implying that the field effect mobilities may be enhanced with proper choice of substrates. The contact resistance between Cr electrodes and the single-layer graphene ribbon was determined to be 1.62 k Omega from the TLM structures.
47.	Makarova, Tatiana L., 1959-, et al. (författare) Induced Ferromagnetism in Helium-Bombarded Graphite 2012 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 12:6, s. 5051-5053 Tidskriftsartikel (refereegranskat)abstract Irradiation with helium ions is an effective method for triggering ferromagnetism in graphite. Chemical inertness of helium suggests that local magnetic moment formation is determined solely by the intrinsic carbon defects created during the target damage. Interacting moments are located in two places: in the vicinity of the sample surface and near the point of maximum defect generation.
48.	Manuel, J., et al. (författare) Synthesis and Electrochemical Properties of Polyaniline Nanofibers by Interfacial Polymerization 2012 Ingår i: Journal of Nanoscience and Nanotechnology. - : American Scientific Publishers. - 1533-4880 .- 1533-4899. ; 12:4, s. 3534-3537 Tidskriftsartikel (refereegranskat)abstract Polyaniline nanofibers were prepared by interfacial polymerization with different organic solvents such as chloroform and carbon tetrachloride. Field emission scanning electron microscopy and transmission electron microscopy were used to study the morphological properties of polyaniline nanofibers. Chemical characterization was carried out using Fourier transform infrared spectroscopy, UV-Vis spectroscopy, and X-ray diffraction spectroscopy and surface area was measured using BET isotherm. Polyaniline nanofibers doped with lithium hexafluorophosphate were prepared and their electrochemical properties were evaluated.
49.	Mugheri, Abdul Qayoom, et al. (författare) A Low Charge Transfer Resistance CuO Composite for Efficient Oxygen Evolution Reaction in Alkaline Media 2021 Ingår i: Journal of Nanoscience and Nanotechnology. - : AMER SCIENTIFIC PUBLISHERS. - 1533-4880 .- 1533-4899. ; 21:4, s. 2613-2620 Tidskriftsartikel (refereegranskat)abstract An efficient, simple, environment-friendly and inexpensive cupric oxide (CuO) electrocatalyst for oxygen evolution reaction (OER) is demonstrated. CuO is chemically deposited on the porous carbon material obtained from the dehydration of common sugar. The morphology of CuO on the porous carbon material is plate-like and monoclinic crystalline phase is confirmed by powder X-ray diffraction. The OER activity of CuO nanostructures is investigated in 1 M KOH aqueous solution. To date, the proposed electrocatalyst has the lowest possible potential of 1.49 V versus RHE (reversible hydrogen electrode) to achieve a current density of 20 mA/cm(2) among the. CuO based electrocatalysts and has Tafel slope of 115 mV dec(-1). The electrocatalyst exhibits an excellent long-term stability for 6 hours along with significant durability. The enhanced catalytic active centers of CuO on the carbon material are due to the porous structure of carbon as well as strong coupling between CuO-C. The functionalization of metal oxides or other related nanostructured materials on porous carbon obtained from common sugar provides an opportunity for the development of efficient energy conversion and energy storage systems.
50.	Mugheri, Abdul Qayoom, et al. (författare) Chemically Coupled Cobalt Oxide Nanosheets Decorated onto the Surface of Multiwall Carbon Nanotubes for Favorable Oxygen Evolution Reaction 2021 Ingår i: Journal of Nanoscience and Nanotechnology. - : AMER SCIENTIFIC PUBLISHERS. - 1533-4880 .- 1533-4899. ; 21:4, s. 2660-2667 Tidskriftsartikel (refereegranskat)abstract Cobalt oxide has been widely investigated among potential transition metal oxides for the electrochemical energy conversion, storage, and water splitting. However, they have inherently low electronic conductivity and high corrosive nature in alkaline media. Herein, we propose a promising and facile approach to improve the conductivity and charge transport of cobalt oxide Co3O4 through chemical coupling with well-dispersed multiwall carbon nanotubes (MWCNTs) during hydrothermal treatment. The morphology of prepared composite material consisting of nanosheets which are anchored on the MWCNTs as confirmed by scanning electron microscopy (SEM). A cubic crystalline system is exhibited by the cobalt oxide as confirmed by the X-ray diffraction study. The Co, O, and C are the only elements present in the composite material. FTIR study has indicated the successful coupling of cobalt oxide with MWCNTs. The chemically coupled cobalt oxide onto the surface of MWCNTs composite is found highly active towards oxygen evolution reaction (OER) with a low onset potential 1.44 V versus RHE, low overpotential 262 mV at 10 mAcm(-2) and small Tafel slope 81 mV dec(-1). For continuous operation of 40 hours during durability test, no decay in activity was recorded. Electrochemical impedance study further revealed a low charge transfer resistance of 70.64 Ohms for the composite material during the electrochemical reaction and which strongly favored OER kinetics. This work provides a simple, low cost, and smartly designing electrocatalysts via hydrothermal reaction for the catalysis and energy storage applications.

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