Search results for "PLASMONIC NANOPARTICLE"
showing 10 items of 16 documents
Plasmonic layers based on Au-nanoparticle-doped TiO2 for optoelectronics: structural and optical properties.
2013
The anti-reflective effect of dielectric coatings used in silicon solar cells has traditionally been the subject of intensive studies and practical applications. In recent years the interest has permanently grown in plasmonic layers based on metal nanoparticles, which are shown to increase light trapping in the underlying silicon. In the present work we have combined these two concepts by means of in situ synthesis of Au nanoparticles in a dielectric matrix (TiO2), which is commonly used as an anti-reflective coating in silicon solar cells, and added the third element: a 10–20% porosity in the matrix. The porosity is formed by means of a controllable wet etching by low concentration HF. As …
A tailor-made nucleoside-based colourimetric probe of formic acid
2014
A ratiometric, specific probe of formic acid has been developed. It is based on intermolecular nucleobase-pairing of inosine-capped plasmonic nanoparticles to form nucleoside channels, which are destabilised by the analyte.
Enhancing carbon dots fluorescence via plasmonic resonance energy transfer
2022
Using plasmonic interactions to engineer optical properties at the nanoscale is an important challenge of current photonics. Here we establish a general strategy to enhance the orange emission of carbon dots by coupling them to gold nanoparticles through a polymeric spacer in solution. We exploit the overlap between the surface plasmon resonance of gold and the electronic transitions of carbon dots to achieve a fivefold increase of their fluorescence in the orange region, which is usually very weak. We demonstrate that this enhancement stems from an ultrafast resonance energy transfer from the coherent plasmonic state of the gold nanoantenna to the coupled carbon dot. Our study advances the…
Protein-membrane interaction probed by single plasmonic nanoparticles.
2008
We present a nanosized and addressable sensor platform based on membrane coated plasmonic particles and show unequivocally the covering with lipid bilayers as well as the subsequent detection of streptavidin binding to biotinylated lipids. The binding is detected on membrane covered gold nanorods by monitoring the spectral shift by fast single particle spectroscopy (fastSPS) on many particles in parallel. Our approach allows for local analysis of protein interaction with biological membranes as a function of the lateral composition of phase separated membranes.
Au-ZnO Nanocomposite Films for Plasmonic Photocatalysis
2015
Nanocomposites based on plasmonic nanoparticles and metal-oxide semiconductors are emerging as promising materials for conversion of solar energy into chemical energy. In this work, a Au–ZnO nanocomposite film with notably enhanced photocatalytic activity is successfully prepared by a single-step process. Both ZnO and Au nanoparticles are synthesized in situ during baking of the film spin-coated from a solution of Zn(CH3COO)2 and HAuCl4. Furthermore, it is shown that this precursor solution can be formulated as a nanoink for the generation of micropatterns by microplotter printing, opening the way for the miniaturization of devices with enhanced properties for photocatalysis, optoelectronic…
Plasmonic nanosensors reveal a height dependence of MinDE protein oscillations on membrane features
2018
6 p.-4 fig.
Self Calibrating Nano-Ruler
2012
The aim of a nanoruler is to measure distances on a length scale in the order of nanometers. This concept can be realized by two plasmonic nanoparticles (usually spheres), which are placed within a short distance to each other. Since the plasmon modes of both particles are coupled, they influence each other along the interparticle axis (i.e. longitudinal plasmon mode, resulting in a shift of the resonance wavelength compared to the single particle. Because the resulting resonance wavelength depends on the interparticle distance, the spectral investigation of such a dimer allows the determination of the interparticle distance.
Single Unlabeled Protein Detection on Individual Plasmonic Nanoparticles
2012
The ultimate detection limit in analytic chemistry and biology is the single molecule. Commonly, fluorescent dye labels or enzymatic amplification are employed. This requires additional labeling of the analyte, which modifies the species under investigation and therefore influences biological processes. Here, we utilize single gold nanoparticles to detect single unlabeled proteins with extremely high temporal resolution. This allows for monitoring the dynamic evolution of a single protein binding event on a millisecond time scale. The technique even resolves equilibrium coverage fluctuations, opening a window into Brownian dynamics of unlabeled macromolecules. Therefore, our method enables …
Coupling colloidal chemistry with coordination chemistry: Design of hybrid nanomaterials by the assembly of plasmonic nanoparticles and functional co…
2021
Nanotechnology involves the design, characterization, production and application of structures, devices and systems by the control of the shape and size at the nanometer scale involving different fields. In the last decade, nanotechnology development has boosted the interest in hybrid nanomaterials. These materials are a complimenting combination of two (or more) nanoparticles (NPs) with enhanced performance characteristics that offer exciting opportunities. It allows the possibility of integrating materials with different physical and chemical properties to widen the range of practical applications. In this context, Au NPs have recently attracted a lot of attention due to the great opportu…
Hot-Carrier Generation in Plasmonic Nanoparticles: The Importance of Atomic Structure
2020
Metal nanoparticles are attractive for plasmon-enhanced generation of hot carriers, which may be harnessed in photochemical reactions. In this work, we analyze the coherent femtosecond dynamics of photon absorption, plasmon formation, and subsequent hot-carrier generation through plasmon dephasing using first-principles simulations. We predict the energetic and spatial hot-carrier distributions in small metal nanoparticles and show that the distribution of hot electrons is very sensitive to the local structure. Our results show that surface sites exhibit enhanced hot-electron generation in comparison to the bulk of the nanoparticle. While the details of the distribution depend on particle s…