Wyniki wyszukiwania dla: au-cu nanostructures
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On the use of Cu catalysts for tailoring carbon nanostructures in alcohol‐CVD
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Transformation of bimetallic Ag–Cu thin films into plasmonically active composite nanostructures
PublikacjaFormation of plasmonically active silver, copper and composite silver-copper nanostructures were studied in this paper. Metallic nanostructures were fabricated by thermal disintegration, so called dewetting, of the thin films in an argon atmosphere. The formation process of the nanostructures was in-situ observed by a novel method, based on resistance measurements. The influence of the material and thickness of the initial thin...
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Tuning of the plasmon resonance location in Au nanostructures coated with a ultrathin film of Al2O3 – Optical measurements and FDTD simulations
PublikacjaThe Au nanostructures have been coated with an ultra-thin films of amorphous aluminium oxide. Optical absorption spectra show the influence of the thickness of Al2O3 on plasmon resonance wavelength. The observed red-shift of the resonance location with the increase of the thickness of the Al2O3 film, can be explained by the change in the dielectric function of this film. It allows control of the optical spectra of the coated particles....
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Temperature of formation of Au nanostructures
Dane BadawczeNanostructures were obtained via annealing of thin Au films. In order to determine possible nanoislands formation mechanisms, dependence on initial film thickness was examined. For the surface morphology studies, nanograin structure and chemical composition analysis, SEM, HR TEM and EDS measurements were performed, respectively. Morphology studies shown...
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Thermally tuneable optical and electrochemical properties of Au-Cu nanomosaic formed over the host titanium dimples
PublikacjaAu-Cu nanostructures offer unique optical and catalytic properties unlike the monometallic ones resulting from the specific interaction. Among others, they have the ability to exhibit surface plasmon resonance, electrochemical activity towards the oxygen and hydrogen evolution reaction (OER, HER) as well as improved photoresponse in relation to monometalic but those properties depend highly on the substrate where bimetallic structures...
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UV-Vis-Induced Degradation of Phenol over Magnetic Photocatalysts Modified with Pt, Pd, Cu and Au Nanoparticles
PublikacjaThe combination of TiO2 photocatalyst and magnetic oxide nanoparticles enhances the separation and recoverable properties of nanosized TiO2 photocatalyst. Metal-modified (Me = Pd, Au, Pt, Cu) TiO2/SiO2@Fe3O4 nanocomposites were prepared by an ultrasonic-assisted sol-gel method. All prepared samples were characterized by X-ray powder diffraction (XRD) analysis, Brunauer-Emmett-Teller (BET) method, X-ray photoelectron spectroscopy...
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Badanie właściwości fotokatalitycznych, biobójczych i magnetycznych tlenku tytanu(IV) modyfikowanego nanocząstkami monoi bimetalicznymi Pt, Ag, Cu, Au oraz Pd
PublikacjaZakres badań obejmował otrzymywanie i charakterystykę nanokompozytów tlenku tytanu(IV) modyfikowanego mono- oraz bimetalicznymi nanocząstkami metali platyny, palladu, złota, srebra oraz miedzi. Zbadano wpływ zawartości metali, matrycy TiO2 oraz połączeniami metali na właściwości fotokatalityczne, biobójcze i magnetyczne otrzymanych nanokompozytów TiO2. Aktywność fotokatalityczną zbadano w reakcji degradacji modelowych związków oraz...
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Au nanostructures coated with a ultrathin film of Al2O3 - measurements and FDTD simulations
Dane BadawczeGold plasmonic platforms have been coated with an ultra-thin films of aluminium oxide. Optical measurements, showing the influence of the thickness of Al2O3 on plasmon resonance position. The observed red-shift of the resonance location with the increase of the thickness of the Al2O3 film, can be explained by the change in the dielectric function of...
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Au–Si plasmonic platforms: synthesis, structure and FDTD simulations
PublikacjaPlasmonic platforms based on Au nanostructures have been successfully synthesized by directional solidification of a eutectic from Au and the substrate. In order to determine homogeneous shape and space distribution, the influence of annealing conditions and the initial thickness of the Au film on the nanostructures was analyzed. For the surface morphology studies, SEM and AFM measurements were performed. The structure of platforms...
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Substrate Dependence in the Formation of Au Nanoislands for Plasmonic Platform Application
PublikacjaIn this work, the influence of the various substrates on Au nanoisland formation has been studied. Nanostructures were obtained via annealing of thin Au films. In order to determine nanoisland formation mechanisms, correlation between an initial film thickness and temperature of formation, shapes, and dimensions of nanostructures was examined. For the surface morphology studies, nanograin structure, and chemical composition analysis,...
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Temperature-controlled nanomosaics of AuCu bimetallic structure towards smart light management
PublikacjaGold–copper nanostructures are promising in solar-driven processes because of their optical, photocatalytic and photoelectrochemical properties, especially those which result from the synergy between the two metals. Increasing interest in their internal structure, such as the composition or distribution of the Au and Cu as well as the size and shape of the nanoparticles, have developed to define their physicochemical properties. In...
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TEM imaging of Ag-Au nanoalloys
Dane BadawczeThe nanostructures of AuAg nanoalloys were prepared by sequential sputtering of metal thin layers (Au/Ag or Ag/Au) followed by annealing under 550 Celsius degree in an argon atmosphere. The basic single layer thickness was usually ca. 3 nm. For investigations two samples wih 50% Au and 50% Ag were selected and samples 1/3 Ag - 2/3 Au and 2/3 Ag - 1/3...
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SEM images of tge gold nanostructures on silicon
Dane BadawczeAu nanostructures were prepared on Si(111) as a substrate. The substrates (1 × 1 cm2 of area) were cleaned with acetylacetone and then rinsed in ethanol. Thin Au films (with thicknesses in a range of 1.7–5.0 nm) were deposited using a table-top dc magnetron sputtering coater (EM SCD 500, Leica) under pure Ar plasma conditions (Argon, Air Products 99.999%)....
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Properties of ordered titanium templates covered with Au thin films for SERS applications
PublikacjatCurrently, roughened metal nanostructures are widely studied as highly sensitive Raman scattering sub-strates that show application potential in biochemistry, food safety or medical diagnostic. In this workthe structural properties and the enhancement effect due to surface enhanced Raman scattering (SERS) ofhighly ordered nano-patterned titanium templates covered with thin (5–20 nm) gold films are reported.The templates are formed...
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Nanostructuring of thin Au films deposited on ordered Ti templates for applications in SERS
PublikacjaIn this work the results on thermal nanostructuring of the Au films on Ti templates as well as morphology and optical properties of the obtained structures are reported. The bimetal nanostructures are fabricated in a multi-step process. First, the titania nanotubes are produced on the surface of Ti foil by anodization in an ethylene glycol-water solution containing fluoride ions. This is followed by chemical etching in oxalic acid...
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Properties of Thermally Dewetted Thin Au Films on ITO-Coated Glass for Biosensing Applications
PublikacjaNoble metal nanostructures are object of great interest due to their unique optical and electronic properties exploited in nanotechnology, medicine, biochemistry, and surface-enhanced spectroscopies. In this work, the Au nanoparticle (NP) structures for application in biosensing obtained by dewetting are investigated in dependence on their preparation conditions. Structures are produced from thin Au films (5–30 nm) sputtered onto...
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Plasmon resonance in gold-silver nanoalloys
Dane BadawczeSurface plasmon resonance (SPR) can lead to improve or formation a new linear or nonlinear optical phenomena. Especially it can enhance a light emission from luminescence materials. The presence of metal nanostructures or nanoparticles is necessary to excitation of the SPR. It is well known that gold and silver nanostructures exhibit plasmon resonance...
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SEM images of dewetted gold films
Dane BadawczeGold nanostructures were prepared on silicon - Si(111) as a substrate. as a result of dewetting process. Thin golds films were deposited using a table-top dc magnetron sputtering coater under pure Ar plasma conditions . The Au target had 99.99% purity, the rate of Au layer deposition was about 0.4 nm·s−1 and the incident power was 32 W. The thickness...
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Formation of gold anostructures detected by SEM microscope
Dane BadawczeGold nanostructures were prepared on silicon - Si(111) as a substrate. The substrates (1 × 1 cm2 of area) were cleaned with acetylacetone and then rinsed in ethanol. Thin Au films (with thicknesses in a range of 1.7–5.0 nm) were deposited using a table-top dc magnetron sputtering coater (EM SCD 500, Leica) under pure Ar plasma conditions (Argon, Air...
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Chemical analysis of the Au-Ag nanoaloys
Dane BadawczeThe nanostructures of AuAg nanoalloys were prepared by sequential sputtering of gold and silver thin films. Single layer thickness was usually 2.8 nm were deosted by magnetron sputtering method in a Ar plasma. As deposited layers were annealed in Ar atmosphere at 550 degress for 15 minutes. For XPS measurements five samples were selected: pure gold...