Search results for "Arrays"
showing 10 items of 122 documents
Photoelectrochemical characterization of Cu2O-nanowire arrays electrodeposited into anodic alumina membranes
2007
Perfectly aligned nanowire arrays of polycrystalline Cu2O were grown by template-pulsed electrodeposition from a cupric acetate-sodium acetate bath into anodic alumina membranes (AAM). The photoelectrochemical behavior of arrays with different nanowire lengths (0.5 mu m and 2 mu m) was investigated in neutral solution, and the results compared to those pertaining to Cu2O films grown with the same procedure. Although all samples displayed the same indirect bandgap (similar to 1.9 eV), differences were observed both in photocurrent intensity and sign. The latter changed with potential and wavelength in different ways for nanowires and films, revealing a different defect concentration in the t…
ZnO/ZnS heterostructures for hydrogen production by photoelectrochemical water splitting
2016
This work studies the photoelectrochemical behavior of novel ZnO/ZnS heterostructures obtained by means of anodization in water and glycerol/water/NH4F electrolytes with different Na2S additions under controlled hydrodynamic conditions. For this purpose different techniques such as Field Emission Scanning Electronic Microscopy (FE-SEM) with EDX, Raman spectroscopy and photoelectrochemical water splitting tests under standard AM 1.5 conditions have been carried out. The obtained results showed that the hydrodynamic conditions promoted an ordered nanotubular morphology which facilitates electron-hole separation and consequently, the photoelectrochemical activity for water splitting is enhance…
High-Density Plasmonic Nanoparticle Arrays Deposited on Nanoporous Anodic Alumina Templates for Optical Sensor Applications
2019
This study demonstrates a new, robust, and accessible deposition technique of metal nanoparticle arrays (NPAs), which uses nanoporous anodic alumina (NAA) as a template for capillary force-assisted convective colloid (40, 60, and 80 nm diameter Au) assembly. The NPA density and nanoparticle size can be independently tuned by the anodization conditions and colloid synthesis protocols. This enables production of non-touching variable-density NPAs with controllable gaps in the 20&ndash
Surface plasmon subwavelength optics.
2003
International audience; Surface plasmons are waves that propagate along the surface of a conductor. By altering the structure of a metal's surface, the properties of surface plasmons- in particular their interaction with light-can be tailored, which offers the potential for developing new types of photonic device. This could lead to miniaturized photonic circuits with length scales that are much smaller than those currently achieved. Surface plasmons are being explored for their potential in subwavelength optics, data storage, light generation, microscopy and bio-photonics.
Space charge limited current mechanism in Bi2S3 nanowires
2016
We report on the charge transport properties of individual Bi2S3 nanowires grown within the pores of anodized aluminum oxide templates. The mean pore diameter was 80 nm. Space charge limited current is the dominating conduction mechanism at temperatures below 160 K. Characteristic parameters of nanowires, such as trap concentration and trap characteristic energy, were estimated from current-voltage characteristics at several temperatures.
Photoconductive properties of Bi2S3nanowires
2015
The photoconductive properties of Bi2S3 nanowires synthesized inside anodized alumina (AAO) membrane have been characterized as a function of illuminating photon energy between the wavelengths of 500 to 900 nm and at constant illumination intensity of 1–4 μW·cm−2. Photoconductivity spectra, photocurrent values, photocurrent onset/decay times of individual Bi2S3 nanowires liberated from the AAO membrane were determined and compared with those of arrays of as-produced Bi2S3 nanowires templated inside pores of AAO membrane. The alumina membrane was found to significantly influence the photoconductive properties of the AAO-hosted Bi2S3 nanowires, when compared to liberated from the AAO membrane…
Time-resolved FDTD and experimental FTIR study of gold micropatch arrays for wavelength-selective mid-infrared optical coupling
2021
The work was partially supported by Sweden's innovation agency Vinnova (Large area CVD graphene-based sensors/IR-photodetectors 2020-00797) and EU CAMART2 project (European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No.739508). TY acknowledges European Regional Development Fund Project No. 1.1.1.2/VIAA/4/20/740.
Colloidal lithography and Metal-Organic Chemical Vapor Deposition process integration to fabricate ZnO nanohole arrays
2010
A complete set up of optimal process conditions for an effective colloidal lithography/catalyst assisted MOCVD process integration is presented. It mainly focuses on the determination of the deposition temperature threshold for ZnO Metal-Organic Chemical Vapour Deposition (MOCVD) as well as the concentration of metal-organic silver (Ag) catalyst. Indeed, the optimization of such process parameters allows to tailor the ZnO film morphology in order to make the colloidal lithography/catalyst assisted MOCVD approach a valuable bottom up method to fabricate bi-dimensional ordered ZnO nanohole arrays. (C) 2010 Elsevier B.V. All rights reserved.
Increase in gut microbiota after immune suppression in baculovirus-infected larvae.
2013
Spodoptera exigua microarray was used to determine genes differentially expressed in S. exigua cells challenged with the species-specific baculovirus SeMNPV as well as with a generalist baculovirus, AcMNPV. Microarray results revealed that, in contrast to the host transcriptional shut-off that is expected during baculovirus infection, S. exigua cells showed a balanced number of up- and down-regulated genes during the first 36 hours following the infection. Many immune-related genes, including pattern recognition proteins, genes involved in signalling and immune pathways as well as immune effectors and genes coding for proteins involved in the melanization cascade were found to be down-regul…
Analyzing Illumina Gene Expression Microarray Data from Different Tissues: Methodological Aspects of Data Analysis in the MetaXpress Consortium
2012
Microarray profiling of gene expression is widely applied in molecular biology and functional genomics. Experimental and technical variations make meta-analysis of different studies challenging. In a total of 3358 samples, all from German population-based cohorts, we investigated the effect of data preprocessing and the variability due to sample processing in whole blood cell and blood monocyte gene expression data, measured on the Illumina HumanHT-12 v3 BeadChip array. Gene expression signal intensities were similar after applying the log(2) or the variance-stabilizing transformation. In all cohorts, the first principal component (PC) explained more than 95% of the total variation. Technic…