Sunday, January 31, 2010

Preparation of Nanoscale Ag Semishell Array with Tunable Interparticle Distance and Its Application in Surface-Enhanced Raman Scattering

Preparation of Nanoscale Ag Semishell Array with Tunable Interparticle Distance and Its Application in Surface-Enhanced Raman Scattering: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Thursday, January 28, 2010

Tuesday, January 26, 2010

Light Emitting Diode Irradiation Can Control the Morphology and Optical Properties of Silver Nanoparticles

Light Emitting Diode Irradiation Can Control the Morphology and Optical Properties of Silver Nanoparticles: "Journal of the American Chemical Society, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Orange−Blue−Orange Triblock One-Dimensional Heterostructures of Organic Microrods for White-Light Emission

Orange−Blue−Orange Triblock One-Dimensional Heterostructures of Organic Microrods for White-Light Emission: "Journal of the American Chemical Society, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Direct Synthesis of Water-Soluble Ultrathin CdS Nanorods and Reversible Tuning of the Solubility by Alkalinity

Direct Synthesis of Water-Soluble Ultrathin CdS Nanorods and Reversible Tuning of the Solubility by Alkalinity: "Journal of the American Chemical Society, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Escherichia coli Bacteria-Templated Synthesis of Nanoporous Cadmium Sulfide Hollow Microrods for Efficient Photocatalytic Hydrogen Production

Escherichia coli Bacteria-Templated Synthesis of Nanoporous Cadmium Sulfide Hollow Microrods for Efficient Photocatalytic Hydrogen Production: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Monday, January 25, 2010

Nanostructured Magnonic Crystals with Size-Tunable Bandgaps

Nanostructured Magnonic Crystals with Size-Tunable Bandgaps: "ACS Nano, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Water-Soluble Fluorescent Silver Nanoclusters

Water-Soluble Fluorescent Silver Nanoclusters: "Ag nanoclusters consist of several to roughly a hundred atoms and possess sizes comparable to the Fermi wavelength of electrons; they exhibit molecule-like properties, including discrete electronic transitions and strong fluorescence. These nanoclusters are of significant interest because they provide the bridge between atomic and nanoparticle behavior in noble metals. Since the first observations of photoluminescence from Ag nanoclusters, substantial effort has been made to prepare Ag nanoclusters and explore their potential applications. The synthesis of well-defined Ag nanoclusters, however, is difficult due to aggregation of nanoclusters, especially in aqueous solutions. In this Research News article, we highlight some recent progress on solution-based synthesis of water-soluble Ag nanoclusters using radiolytic, chemical reduction and photochemical approaches to prepare fluorescent Ag nanoclusters."

Near-infrared photocatalysis based on YF3:Yb3+,Tm3+/TiO2 core/shell nanoparticles

Near-infrared photocatalysis based on YF3:Yb3+,Tm3+/TiO2 core/shell nanoparticles: "


Weiping Qin, Daisheng Zhang, Dan Zhao, Lili Wang, Kezhi Zheng

(Communication from Chem. Commun.)

Weiping Qin, Chem. Commun., 2010, DOI: 10.1039/b924052g

To cite this article before page numbers are assigned, use the DOI form of citation above.


The content of this RSS Feed (c) The Royal Society of Chemistry"

Plasmon Coupling in Two-Dimensional Arrays of Silver Nanoparticles: II. Effect of the Particle Size and Interparticle Distance†

Plasmon Coupling in Two-Dimensional Arrays of Silver Nanoparticles: II. Effect of the Particle Size and Interparticle Distance†: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Investigation of Hydrogen Storage Capabilities of ZnO-Based Nanostructures

Investigation of Hydrogen Storage Capabilities of ZnO-Based Nanostructures: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Melting Characteristics of Superlattices of Alkanethiol-Capped Gold Nanoparticles: The “Excluded” Story of Excess Thiol

Melting Characteristics of Superlattices of Alkanethiol-Capped Gold Nanoparticles: The “Excluded” Story of Excess Thiol: "Chemistry of Materials, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Sunday, January 24, 2010

Formation and Assembly−Disassembly Processes of ZnO Hexagonal Pyramids Driven by Dipolar and Excluded Volume Interactions

Formation and Assembly−Disassembly Processes of ZnO Hexagonal Pyramids Driven by Dipolar and Excluded Volume Interactions: "Journal of the American Chemical Society, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Significantly Enhanced Red Photoluminescence Properties of Nanocomposite Films Composed of a Ferroelectric Bi3.6Eu0.4Ti3O12 Matrix and Highly c-Axis-Oriented ZnO Nanorods on Si Substrates Prepared by a Hybrid Chemical Solution Method

Significantly Enhanced Red Photoluminescence Properties of Nanocomposite Films Composed of a Ferroelectric Bi3.6Eu0.4Ti3O12 Matrix and Highly c-Axis-Oriented ZnO Nanorods on Si Substrates Prepared by a Hybrid Chemical Solution Method: "Journal of the American Chemical Society, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Synthesis of Triangular Silver Nanoprisms by Stepwise Reduction of Sodium Borohydride and Trisodium Citrate

Synthesis of Triangular Silver Nanoprisms by Stepwise Reduction of Sodium Borohydride and Trisodium Citrate: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

A Facile Route to ZnO Nanoparticle Superlattices: Synthesis, Functionalization, and Self-Assembly

A Facile Route to ZnO Nanoparticle Superlattices: Synthesis, Functionalization, and Self-Assembly: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

A High-Efficiency Surface-Enhanced Raman Scattering Substrate Based on Silicon Nanowires Array Decorated with Silver Nanoparticles

A High-Efficiency Surface-Enhanced Raman Scattering Substrate Based on Silicon Nanowires Array Decorated with Silver Nanoparticles: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

A High-Efficiency Surface-Enhanced Raman Scattering Substrate Based on Silicon Nanowires Array Decorated with Silver Nanoparticles

A High-Efficiency Surface-Enhanced Raman Scattering Substrate Based on Silicon Nanowires Array Decorated with Silver Nanoparticles: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Quantitative Analysis of Electron Transfer between Ce3+(5d1) and Yb3+/Eu3+ Ions in Y3Al5O12 and Lu2Si2O7

Quantitative Analysis of Electron Transfer between Ce3+(5d1) and Yb3+/Eu3+ Ions in Y3Al5O12 and Lu2Si2O7: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Size-Tunable and Functional Core−Shell Structured Silica Nanoparticles for Drug Release

Size-Tunable and Functional Core−Shell Structured Silica Nanoparticles for Drug Release: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Nonhydrolytic Route for Synthesis of ZnO and Its Use as a Recyclable Photocatalyst

Nonhydrolytic Route for Synthesis of ZnO and Its Use as a Recyclable Photocatalyst: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

The Hidden Effects of Particle Shape and Criteria for Evaluating the Upconversion Luminescence of the Lanthanide Doped Nanophosphors

The Hidden Effects of Particle Shape and Criteria for Evaluating the Upconversion Luminescence of the Lanthanide Doped Nanophosphors: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Self-Assembled 3D Urchin-Like NaY(MoO4)2:Eu3+/Tb3+ Microarchitectures: Hydrothermal Synthesis and Tunable Emission Colors

Self-Assembled 3D Urchin-Like NaY(MoO4)2:Eu3+/Tb3+ Microarchitectures: Hydrothermal Synthesis and Tunable Emission Colors: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Influence of Water Temperature on the Hydrodynamic Diameter of Gold Nanoparticles from Laser Ablation

Influence of Water Temperature on the Hydrodynamic Diameter of Gold Nanoparticles from Laser Ablation: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Effect of CdSe Nanoparticles on the Growth of Te Nanowires: Greater Length and Tortuosity and Nonmonotonic Concentration Effect

Effect of CdSe Nanoparticles on the Growth of Te Nanowires: Greater Length and Tortuosity and Nonmonotonic Concentration Effect: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Bright and Stable Purple/Blue Emitting CdS/ZnS Core/Shell Nanocrystals Grown by Thermal Cycling Using a Single-Source Precursor

Bright and Stable Purple/Blue Emitting CdS/ZnS Core/Shell Nanocrystals Grown by Thermal Cycling Using a Single-Source Precursor: "Chemistry of Materials, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Solution-Based Epitaxial Growth of Magnetically Responsive Cu@Ni Nanowires

Solution-Based Epitaxial Growth of Magnetically Responsive Cu@Ni Nanowires: "Chemistry of Materials, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Efficient Dye-Sensitized Solar Cells with an Organic Photosensitizer Featuring Orderly Conjugated Ethylenedioxythiophene and Dithienosilole Blocks

Efficient Dye-Sensitized Solar Cells with an Organic Photosensitizer Featuring Orderly Conjugated Ethylenedioxythiophene and Dithienosilole Blocks: "Chemistry of Materials, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Fabrication and luminescent properties of CaWO4:Ln3+ (Ln = Eu, Sm, Dy) nanocrystals

Fabrication and luminescent properties of CaWO4:Ln3+ (Ln = Eu, Sm, Dy) nanocrystals: "

Abstract  Scheelite CaWO4 doped with rare earth ions (Eu3+, Sm3+, Dy3+) were fabricated via a facile solvothermal process without further heat treatment, which used sodium oleate and oleylamine
as capping reagent. The structure, morphology, and optical properties of the samples were well characterized by X-ray diffraction
(XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), high-resolution transmission
electron microscope (HRTEM), X-ray photoelectron spectra (XPS), photoluminescence (PL) spectra and cathodoluminescence (CL).
The XRD results reveal that all the doped samples are well assigned to the scheelite structure of the CaWO4 phase. Upon excitation by ultraviolet radiation, the CaWO4:Eu3+ phosphors show the characteristic 5D07F1–3 emission lines of Eu3+, and the CaWO4:Sm3+ phosphors demonstrate the characteristic 4G5/26H5/2–9/2 emission line of Sm3+, and the CaWO4:Dy3+ phosphors demonstrate the characteristic 4F9/26H13/2–15/2 emission line of Dy3+.


  • Content Type Journal Article
  • Category Comm. on novel techn. and applications
  • DOI 10.1007/s11051-010-9850-4
  • Authors

    • Wenxin Wang, Harbin Engineering University College of Material Science and Chemical Engineering 150001 Harbin People’s Republic of China
    • Piaoping Yang, Harbin Engineering University College of Material Science and Chemical Engineering 150001 Harbin People’s Republic of China
    • Shili Gai, Harbin Engineering University College of Material Science and Chemical Engineering 150001 Harbin People’s Republic of China
    • Na Niu, Harbin Engineering University College of Material Science and Chemical Engineering 150001 Harbin People’s Republic of China
    • Fei He, Harbin Engineering University College of Material Science and Chemical Engineering 150001 Harbin People’s Republic of China
    • Jun Lin, Chinese Academy of Sciences State Key Laboratory of Application of Rare Earth Resources, Changchun Institute of Applied Chemistry 130022 Changchun People’s Republic of China


"

The use of colloidal ferrofluid as building blocks for nanostructured layer-by-layer films fabrication

The use of colloidal ferrofluid as building blocks for nanostructured layer-by-layer films fabrication: "

Abstract  The electrostatic layer-by-layer technique has been exploited as an useful strategy for fabrication of nanostructured thin
films, in which specific properties can be controlled at the molecular level. Ferrofluids consist of a colloidal suspension
of magnetic grains (with only a few nanometers of diameter) with present interesting physical properties and applications,
ranging from telecommunication to drug delivery systems. In this article, we developed a new strategy to manipulate ferrofluids
upon their immobilization in nanostructured layered films in conjunction with conventional polyelectrolytes using the layer-by-layer
technique. We investigated the morphological, optical, and magnetic properties of the immobilized ferrofluid as a function
of number of bilayers presented in the films. Ferrofluid/polyelectrolyte multilayers homogeneously covered the substrates
surface, and the magnetic and optical properties of films exhibited a linear dependence on the number of bilayers adsorbed.


  • Content Type Journal Article
  • Category Research Paper
  • DOI 10.1007/s11051-010-9855-z
  • Authors

    • A. Pereira, Universidade Federal de Santa Catarina Departamento de Física Florianópolis SC 88040-900 Brazil
    • S. Alves, Universidade Federal de São Paulo Departamento de Ciências Exatas e da Terra de Física Diadema SP 09972-270 Brazil
    • M. Casanova, Universidade de São Paulo Instituto de Física de São Carlos P.O. Box 369 São Carlos SP 13560-970 Brazil
    • V. Zucolotto, Universidade de São Paulo Instituto de Física de São Carlos P.O. Box 369 São Carlos SP 13560-970 Brazil
    • I. H. Bechtold, Universidade Federal de Santa Catarina Departamento de Física Florianópolis SC 88040-900 Brazil


"

Nanoscale Resolution, Multicomponent Biomolecular Arrays Generated By Aligned Printing With Parylene Peel-Off

Nanoscale Resolution, Multicomponent Biomolecular Arrays Generated By Aligned Printing With Parylene Peel-Off: "Nano Letters, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Tuesday, January 19, 2010

Conversion of Ag Nanowires to AgCl Nanowires Decorated with Au Nanoparticles and Their Photocatalytic Activity

Conversion of Ag Nanowires to AgCl Nanowires Decorated with Au Nanoparticles and Their Photocatalytic Activity: "

Yugang Sun
Center for Nanoscale Materials, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439
J. Phys. Chem. C2010114 (5), pp 2127–2133
DOI: 10.1021/jp9115645
Publication Date (Web): January 19, 2010
Copyright © 2010 American Chemical Society



A two-step approach has been developed to synthesize AgCl nanowires decorated with Au nanoparticles by using Ag nanowires as chemical templates. In the first step, the Ag nanowires are oxidized with FeCl3 followed by a simultaneous precipitation reaction between Ag+ and Cl ions at room temperature, resulting in conversion of the Ag nanowires to AgCl nanowires as well as reduction of Fe3+ to Fe2+ ions. In the second step, the Fe2+ ions generated in the first step reduce Au precursors (e.g., NaAuCl4) to deposit Au nanoparticles on the surfaces of the AgCl nanowires, resulting in the formation of AgCl:Au composite nanowires. Because of strong surface plasmon resonance and chemical inertness of Au nanoparticles, the as-synthesized AgCl:Au nanowires exhibit enhanced absorption coefficient in the visible region and enhanced chemical stability to prevent them from degradation and aggregation. These unique properties enable the AgCl:Au nanowires to be used as a class of promising plasmonic photocatalysts driven by visible light. Preliminary results demonstrate these composite nanowires can efficiently decompose organics, such as methylene blue molecules, under illumination of white light.

Magnetic Resonance Imaging Contrast Agents Based on Iron Oxide Superparamagnetic Ferrofluids

Magnetic Resonance Imaging Contrast Agents Based on Iron Oxide Superparamagnetic Ferrofluids: "Chemistry of Materials, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Effect of Reduced Particle Size on the Magnetic Properties of Chemically Synthesized BiFeO3 Nanocrystals

Effect of Reduced Particle Size on the Magnetic Properties of Chemically Synthesized BiFeO3 Nanocrystals: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

A facile method for preparation of lanthanide-doped titania-coated silica nanoparticles

A facile method for preparation of lanthanide-doped titania-coated silica nanoparticles: "

Abstract  Here, we report a facile method for the preparation of monodisperse lanthanide-doped titania-coated silica nanoparticles.
By hydrolysis of titanium alkoxide precursors in the presence of lanthanide ions, titania coatings have been deposited on
the surface of the silica nanoparticles dispersed in the pure ethanol. Lanthanide ions were directly incorporated into the
coating during the coating process. For a given ratio of titanium alkoxide to water, the density of the doped ions is determined
by the concentration of the lanthanide ions in the reactant mixture. The final particles were nanosized, discrete, and exhibiting
luminescence when excited.


  • Content Type Journal Article
  • DOI 10.1007/s10853-009-4201-5
  • Authors

    • Shujie Pang, Jilin University Key Lab of Supramolecular Structure and Materials, College of Chemistry 2699# Qian Jin Avenue Changchun 130012 People’s Republic of China
    • Xianliang Li, Jilin University Key Lab of Supramolecular Structure and Materials, College of Chemistry 2699# Qian Jin Avenue Changchun 130012 People’s Republic of China
    • Guang Yang, DaQing Normal University Chemistry and Chemical Engineer Department Central Street Daqing Ranghulu District 163712 People’s Republic of China
    • Zuosen Shi, Jilin University Key Lab of Supramolecular Structure and Materials, College of Chemistry 2699# Qian Jin Avenue Changchun 130012 People’s Republic of China
    • Ying Wan, Jilin University Key Lab of Supramolecular Structure and Materials, College of Chemistry 2699# Qian Jin Avenue Changchun 130012 People’s Republic of China
    • Zhanchen Cui, Jilin University Key Lab of Supramolecular Structure and Materials, College of Chemistry 2699# Qian Jin Avenue Changchun 130012 People’s Republic of China


"

Selective Synthesis and Luminescence Properties of Self-Assembled SrMoO4 Superstructures via a Facile Sonochemical Route

Selective Synthesis and Luminescence Properties of Self-Assembled SrMoO4 Superstructures via a Facile Sonochemical Route: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Thursday, January 14, 2010

Structure, electrical, and optical properties of ZnO-substituted PbO for the Er3+/Yb3+ co-doped Bi2O3–GeO2–Na2O glass system

Structure, electrical, and optical properties of ZnO-substituted PbO for the Er3+/Yb3+ co-doped Bi2O3–GeO2–Na2O glass system: "

Abstract  Glasses of the 0.5Er3+/2.5Yb3+ co-doped (40Bi2O3–20GeO2–(30 − x)PbO–xZnO–10Na2O system where x = 0.0, 5, 10, 15, 20, 25, and 30 mol%) have been characterized by FT-IR spectroscopy measurements to obtain information about
the influence of ZnO-substituted PbO on the local structure of the glass matrix. The density and the molar volume have been
determined. The influences of the ZnO-substituted PbO on the structure of glasses have been discussed. The dc conductivity
measured in the temperature range 475–700 K obeys Arrhenius law. The conductivity decreases while the activation energy for
conduction increases with increase ZnO content. The optical transmittance and reflectance spectrum of the glasses have been
recorded in the wavelength range 400–1100 nm. The values of the optical band gap E
opt for all types of electronic transitions and refractive index have been determined and discussed. The real and imaginary parts
ε1 and ε2 of dielectric constant have been determined.


  • Content Type Journal Article
  • DOI 10.1007/s10853-009-4167-3
  • Authors

    • Shaaban M. Salem, Al Azhar University Department of Physics, Faculty of Science Nasr City 11884 Cairo Egypt
    • I. Shaltout, Al Azhar University Department of Physics, Faculty of Science Nasr City 11884 Cairo Egypt


"

Silver Dendrites from Galvanic Displacement on Commercial Aluminum Foil As an Effective SERS Substrate

Silver Dendrites from Galvanic Displacement on Commercial Aluminum Foil As an Effective SERS Substrate: "Journal of the American Chemical Society, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Atomic Displacement Parameters of Ceria Doped with Rare-Earth Oxide Ce0.8R0.2O1.9 (R = La, Nd, Sm, Gd, Y, and Yb) and Correlation with Oxide-Ion Conductivity

Atomic Displacement Parameters of Ceria Doped with Rare-Earth Oxide Ce0.8R0.2O1.9 (R = La, Nd, Sm, Gd, Y, and Yb) and Correlation with Oxide-Ion Conductivity: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Synthesis of Nanorod-Shaped Cobalt Hydroxycarbonate and Oxide with the Mediation of Ethylene Glycol

Synthesis of Nanorod-Shaped Cobalt Hydroxycarbonate and Oxide with the Mediation of Ethylene Glycol: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Highly bacterial resistant silver nanoparticles: synthesis and antibacterial activities

Highly bacterial resistant silver nanoparticles: synthesis and antibacterial activities: "

Abstract  In this article, we describe a simple one-pot rapid synthesis route to produce uniform silver nanoparticles by thermal reduction
of AgNO3 using oleylamine as reducing and capping agent. To enhance the dispersal ability of as-synthesized hydrophobic silver nanoparticles
in water, while maintaining their unique properties, a facile phase transfer mechanism has been developed using biocompatible
block co-polymer pluronic F-127. Formation of silver nanoparticles is confirmed by X-ray diffraction (XRD), transmission electron
microscopy (TEM) and UV–vis spectroscopy. Hydrodynamic size and its distribution are obtained from dynamic light scattering
(DLS). Hydrodynamic size and size distribution of as-synthesized and phase transferred silver nanoparticles are 8.2 ± 1.5 nm
(σ = 18.3%) and 31.1 ± 4.5 nm (σ = 14.5%), respectively. Antimicrobial activities of hydrophilic silver nanoparticles is tested
against two Gram positive (Bacillus megaterium and Staphylococcus aureus), and three Gram negative (Escherichia
coli, Proteus
vulgaris and Shigella
sonnei) bacteria. Minimum inhibitory concentration (MIC) values obtained in the present study for the tested microorganisms are
found much better than those reported for commercially available antibacterial agents.


  • Content Type Journal Article
  • Category Research Paper
  • DOI 10.1007/s11051-009-9845-1
  • Authors

    • Bhupendra Chudasama, Thapar University School of Physics & Materials Science Patiala 147004 India
    • Anjana K. Vala, Bhavnagar University Department of Physics Bhavnagar 364022 India
    • Nidhi Andhariya, Bhavnagar University Department of Physics Bhavnagar 364022 India
    • R. V. Mehta, Bhavnagar University Department of Physics Bhavnagar 364022 India
    • R. V. Upadhyay, Charotar University of Science and Technology P.D. Patel Institute of Applied Sciences Education Campus Changa 388421 India


"

Study of energy transfer from capping agents to intrinsic vacancies/defects in passivated ZnS nanoparticles

Study of energy transfer from capping agents to intrinsic vacancies/defects in passivated ZnS nanoparticles: "

Abstract  The study of energy transfer mechanism from different capping agents to intrinsic luminescent vacancy centres of zinc sulphide
(ZnS) has been reported in the present work. Nanoparticles of capped and uncapped ZnS are prepared by co-precipitation reaction.
These nanoparticles are sterically stabilized using organic polymers—poly vinyl pyrrolidone, 2-mercaptoethanol and thioglycerol.
Monodispersed nanoparticles were observed under TEM for both capped and uncapped ZnS nanopowders. However, for uncapped ZnS
nanopowders, tendency for formation of nanorod like structure exists. Size of ZnS crystallites was calculated from X-ray diffraction
pattern. The primary crystallite size estimated from X-ray diffraction pattern is 1.95–2.20 nm for capped nanostructures and
2.2 nm for uncapped nanostructures. FTIR spectra were conducted to confirm capping. Zeta potential measurements have been
done to check the stability of dispersed nanoparticles. Band gap measurement was done by UV–visible spectrophotometer. Excitation
and emission spectra are also performed in order to compare optical properties in various samples. Increase in emission intensity
and band gap has been observed by adding different capping agents in comparison to uncapped ZnS nanoparticles. The results
show that in capped ZnS nanoparticles the mechanism of energy transfer from capping layer to photoluminescent vacancy centres
is more pronounced.


  • Content Type Journal Article
  • Category Research Paper
  • DOI 10.1007/s11051-009-9844-2
  • Authors

    • Manoj Sharma, Thapar University School of Physics and Materials Science Patiala 147 004 Punjab India
    • Sunil Kumar, Maharishi Markandeshwar University Department of Physics Mullana, Ambala 133 203 India
    • O. P. Pandey, Thapar University School of Physics and Materials Science Patiala 147 004 Punjab India


"

Monday, January 11, 2010

Electrosynthesis of SER-Active Silver Nanopillar Electrode Arrays†

Electrosynthesis of SER-Active Silver Nanopillar Electrode Arrays†: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Small Gold Nanoparticles Synthesized with Sodium Citrate and Heavy Water: Insights into the Reaction Mechanism

Small Gold Nanoparticles Synthesized with Sodium Citrate and Heavy Water: Insights into the Reaction Mechanism: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Optical Properties of Nested Pyramidal Nanoshells†

Optical Properties of Nested Pyramidal Nanoshells†: "The Journal of Physical Chemistry C, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Ultrasound assisted one pot synthesis of nano-sized CuO and its nanocomposite with poly(vinyl alcohol)

Ultrasound assisted one pot synthesis of nano-sized CuO and its nanocomposite with poly(vinyl alcohol): "

Abstract  The ultrasound (US) assisted one pot method has used to synthesize CuO nanoparticles. The fourier transform infrared spectroscopy
(FTIR) spectrum shows a characteristic peak of metal–oxygen bond at 535 cm−1, which confirms the CuO formation. The high resolution transmission electron microscope (HRTEM) images of the synthesized
nano-CuO confirms the size of nanorods with the length of approximately 25–30 nm, and its breadth is less than one nanometer.
X-ray diffraction (XRD) pattern of CuO can be readily assigned to those of crystalline CuO, indicating the formation of single-phase
CuO with monoclinic structure. The synthesized nano-CuO is mixed with poly(vinyl alcohol) (PVA) to prepare the PVA/CuO nanocomposite
to improve the thermal stability of PVA. Their physico-chemical properties are examined by means of FTIR, XRD, differential
scanning calorimetry, thermogravimetric analysis, HRTEM, and scanning electron microscope (SEM) techniques.


  • Content Type Journal Article
  • DOI 10.1007/s10853-009-4158-4
  • Authors

    • S. Gandhi, Kamaraj College of Engineering and Technology Department of Polymer Technology Virdhunagar 626 001 Tamilnadu India
    • R. Hari Hara Subramani, Kamaraj College of Engineering and Technology Department of Polymer Technology Virdhunagar 626 001 Tamilnadu India
    • T. Ramakrishnan, Kamaraj College of Engineering and Technology Department of Polymer Technology Virdhunagar 626 001 Tamilnadu India
    • A. Sivabalan, Kamaraj College of Engineering and Technology Department of Polymer Technology Virdhunagar 626 001 Tamilnadu India
    • V. Dhanalakshmi, Kamaraj College of Engineering and Technology Department of Polymer Technology Virdhunagar 626 001 Tamilnadu India
    • M. R. Gopinathan Nair, M.G. University School of Chemical Sciences Kottayam 686 560 Kerala India
    • R. Anbarasan, National Taiwan University MEMS Thermal Control Lab, Department of Mechanical Engineering Taipei 10617 Taiwan, ROC


"

Alternating Silica/Polymer Multilayer Hybrid Microspheres Templates for Double-shelled Polymer and Inorganic Hollow Microstructures

Alternating Silica/Polymer Multilayer Hybrid Microspheres Templates for Double-shelled Polymer and Inorganic Hollow Microstructures: "Chemistry of Materials, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."

Synthesis of composite gold/tin-oxide nanoparticles by nano-soldering

Synthesis of composite gold/tin-oxide nanoparticles by nano-soldering: "

Abstract  Composite Au–SnO2 nanoparticles (NPs) are synthesized by nano-soldering of pure Au and SnO2 NPs. The multi-step process involves synthesis of pure Au and SnO2 NPs separately by nanosecond pulse laser ablation of pure gold and pure tin targets in deionized water and post-ablation
laser heating of mixed solution of Au colloidal and SnO2 colloidal to form nanocomposite. Transmission Electron Microscopy (TEM) and High-Resolution Transmission Electron Microscopy
(HRTEM) were used to study the effect of laser irradiation time on morphology of the composite Au–SnO2 NPs. The spherical particles of 4 nm mean size were obtained for 5 min of post-laser heating. Increased mean size and elongated
particles were observed on further laser heating. UV–vis spectra of Au–SnO2 nanocomposites show red shift in the plasmon resonance absorption peak and line shape broadening with respect to pure Au
NPs. The negative binding energy shift of Au 4f7/2 peak observed in X-ray Photoelectron Spectra (XPS) indicates charge transfer in the nano-soldered Au–SnO2 between gold and tin oxide and formation of soldered nanocomposite.


  • Content Type Journal Article
  • Category Research Paper
  • DOI 10.1007/s11051-009-9836-2
  • Authors

    • Geetika Bajaj, Indian Institute of Technology Delhi Department of Physics New Delhi 110016 India
    • R. K. Soni, Indian Institute of Technology Delhi Department of Physics New Delhi 110016 India


"

Stoichiometry of BaTiO3 nanoparticles

Stoichiometry of BaTiO3 nanoparticles: "

Abstract  Barium titanate nanoparticles with various nominal Ba/Ti ratios were prepared through direct synthesis from solution (DSS)
and further annealed at different temperatures. Their deviation from stoichiometry was studied through XRD analysis, and a
large deviation from stoichiometry has been observed. The grain size we studied ranges from 50 nm to 1 Î¼m. For the as-prepared
particles, the grain size is about 50 nm, and the maximum excess of Ti is over 15%. For the samples annealed at 800 °C, the
grain size is increased to 100 nm, and the maximum excesses of Ba and Ti are 8 and 9%, respectively. The defects formed during
synthesis and surface effect of nanoparticles are both estimated for their contributions to the deviation from stoichiometry,
and the defects have been found to be mainly responsible for the large deviation observed.


  • Content Type Journal Article
  • Category Research Paper
  • DOI 10.1007/s11051-009-9838-0
  • Authors

    • Jian Quan Qi, Tsinghua University Department of Materials Sciences & Engineering, State Key Laboratory of Fine Ceramics and New Processing Beijing 100084 China
    • Li Sun, Tsinghua University Department of Materials Sciences & Engineering, State Key Laboratory of Fine Ceramics and New Processing Beijing 100084 China
    • Peng Du, Tsinghua University Department of Materials Sciences & Engineering, State Key Laboratory of Fine Ceramics and New Processing Beijing 100084 China
    • Wan Ping Chen, Wuhan University Department of Physics Wuhan 430072 China
    • You Guo Xu, Tsinghua University Department of Materials Sciences & Engineering, State Key Laboratory of Fine Ceramics and New Processing Beijing 100084 China
    • Long Tu Li, Tsinghua University Department of Materials Sciences & Engineering, State Key Laboratory of Fine Ceramics and New Processing Beijing 100084 China


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Biosynthesis of gold and silver nanoparticles by natural precursor clove and their functionalization with amine group

Biosynthesis of gold and silver nanoparticles by natural precursor clove and their functionalization with amine group: "

Abstract  We report a simple and cost effective way for synthesis of metallic nanoparticles (Au and Ag) using natural precursor clove.
Au and Ag nanoparticles have been synthesized by reducing the aqueous solution of AuCl4 and AgNO3 with clove extract. One interesting aspect here is that reduction time is quite small (few minutes instead of hours as compared
to other natural precursors). We synthesized gold and silver nanoparticles of different shape and size by varying the ratio
of AuCl4 and AgNO3 with respect to clove extract, where the dominant component is eugenol. The evolution of Au and Ag nanoparticles from the
reduction of different ratios of AuCl4 and AgNO3 with optimised concentration of the clove extract has been evaluated through monitoring of surface plasmon behaviour as a
function of time. The reduction of AuCl4 and AgNO3 by eugenol is because of the inductive effect of methoxy and allyl groups which are present at ortho and para positions of
proton releasing –OH group as two electrons are released from one molecule of eugenol. This is followed by the formation of
resonating structure of the anionic form of eugenol. The presence of methoxy and allyl groups has been confirmed by FTIR.
To the best of our knowledge, use of clove as reducing agent, the consequent very short time (minutes instead of hours and
without any scavenger) and the elucidation of mechanism of reduction based on FTIR analysis has not been attempted earlier.


  • Content Type Journal Article
  • Category Research Paper
  • DOI 10.1007/s11051-009-9835-3
  • Authors

    • Ashwani Kumar Singh, Banaras Hindu University Nanoscience and Nanotechnology Unit, Department of Physics Varanasi 221005 India
    • Mahe Talat, Banaras Hindu University Nanoscience and Nanotechnology Unit, Department of Physics Varanasi 221005 India
    • D. P. Singh, Southern Illinois University Carbondale Department of Physics Lincoln, Carbondale IL 62901-4401 USA
    • O. N. Srivastava, Banaras Hindu University Nanoscience and Nanotechnology Unit, Department of Physics Varanasi 221005 India


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White Light-Emitting Diodes Based on Ultrasmall CdSe Nanocrystal Electroluminescence

White Light-Emitting Diodes Based on Ultrasmall CdSe Nanocrystal Electroluminescence: "Nano Letters, Volume 0, Issue 0, Articles ASAP (As Soon As Publishable)."