We present a study of resonant optical properties gold‐protected silver nanoisland films. Silver nanoislands were grown on glass substrate using out‐diffusion technique, the growth was followed by deposition nanometer‐thick gold coatings. Scanning electron microscopy and spectroscopy used to characterize morphology extinction spectra combined silver–gold nanostructures. Micro Raman has demonstrated their signal enhancement factor exceeding that one initial nanoislands.

The problem of optimizing the topography metal structures allowing Surface Enhanced Raman Scattering (SERS) sensing is considered. We developed a model, which randomly distributes hemispheroidal particles over given area glass substrate and estimates SERS capabilities obtained structures. applied Power Spectral Density (PSD) analysis to modeled atomic force microscope images widely used in island films dendrites. comparison measured calculated signals from differing characteristics with...

The statistics of hot spots in the ensemble self-assembled silver nanoislands grown on surface silver-to-sodium ion exchanged glass under hydrogen annealing was studied. comparison enhanced Raman scattering (SERS) performance nanoisland films at different growth stages with developed model formation revealed that coalescence stage enhancement is dominated by increase electric field spots, not their density. At earlier stages, linear relation between SERS signal and density expected.

An ensemble of hemiellipsoidally shaped silver nanoislands was grown on a soda-lime glass substrate using the combination ion exchange, thermal poling, and out-diffusion techniques. The were characterized scanning electron atomic force microscopy, their dipole quadrupole plasmonic properties studied dark-field spectroscopy numerical modeling discrete approximation finite element analysis. Numerically simulated scattering spectra demonstrate good correspondence with single-particle...

For the first time we show that introduction of silver ions in glass containing gold nanoparticles (NPs) and additional heat treatment air lead to formation Au/Ag alloy NPs. The proposed approach makes it possible position localized surface plasmon resonance NPs by selecting temperature, which determines proportion This allows for expanding customizability applications surface-enhanced Raman scattering spectroscopy, catalysis biochemistry. Developed technique benefits from presence ionic...

The irradiation of silver-to-sodium ion-exchanged glass with 1.06-μm nanosecond laser pulses mJ-range energy results in the formation silver nanoparticles under surface. Following chemical removal ~25-nm layer reveals a pattern capable surface enhancement Raman scattering (SERS). formed when are more than half-overlapped provides up to ~105 and uniform SERS signal distribution, while decrease pulse overlap an order magnitude higher but less enhancement.

Abstract It has been demonstrated that thermally poled regions of silicate glasses are capable blocking penetration silver ions into the in course ion exchange processing. This allows using locally glass surface as thick dielectric masks formation exchanged structures, like channel optical waveguides, substrates. approach provides easy multiplication structures and, being based on thermal electric field imprinting masks, avoiding both lithography with use liquid chemicals and influence metal...

We investigated the stability of silver nanoisland films, which were formed on glass surface by method out-diffusion, in biocompatible buffers and applicability films enhanced Raman scattering (SERS). have shown that are stable one most widespread biological studies buffer-phosphate buffer saline (PBS), 1:100 water-diluted PBS, PBS-based buffer, NaCl is replaced same amount NaClO4, acidic phosphate buffer. At time, replacement PBS N(CH3)4Cl leads to degradation nanoislands. It was after...

Abstract Broadband dielectric spectroscopy (BDS) was applied to study polarization phenomena in alkaline silicate glasses, particular, properties and structure of subsurface (anodic) polarized layers forming poling with deposited film electrodes different structures. A model poled glasses which does not contradict experimental data is proposed. In accordance the model, a glass presented as two resistor‐capacitor circuits series connection, one layer another rest sample. It found that...

We studied the surface-enhanced Raman spectra of amino acids

Abstract We demonstrate for the first time that results of ion exchange processing thermally poled soda-lime glass essentially depend on poling conditions. In particular, vacuum-poled in silver-sodium nitrate melt diffusion and reduction silver ions followed by clustering nanoparticles subsurface layer after either ion-exchange or additional heat treatment ion-exchanged samples. Poling air atmosphere with deposited gold film anode prevents penetration glass, but electric field stimulated...

We studied surface enhanced Raman spectra of amino acids D-alanine and DL-serine their mixture on silver nanoisland films (SNF), immersed in phosphate buffer saline solution at millimolar acid concentrations. It is shown that the from solutions differ reference for microcrystallites due to electrostatic orientation zwitterions by metal film. Moreover, non-additive peaks are observed spectrum adsorbed SNF, which means intermolecular interactions between very significant. The results indicate...

Abstract Silver-gold alloy nanoparticles were grown using heat treatment of soda-lime glass slides with depercolated gold film subjected to silver-to-sodium ion exchange. Varying the regime allows one control proportion silver in and adjust spectral position their local surface plasmon resonance (LSPR) range between resonances nanoparticles. The LSPR can be shifted by 15% via dilution 50 wt % concentration. This shift is accompanied only a 3% decrease HeLa cell viability on slight...

We present the atomistic model and simulation of a self-assembled growth silver nanoisland film small groups nanoislands on glass substrate after thermal poling with profiled electrode. The calculations were performed in molecular dynamics simulator LAMMPS taking into account diffusion metal atoms towards along surface their clustering. Lennard-Jones potential was used to describe metal-metal metal-glass interaction. parameters determined provide qualitative coincidence simulated...

Abstract We used thermal poling structuring of glass samples followed by chemical etching and subsequent out-diffusion growth silver nanoparticles to fabricate periodic arrays grooves etched in the with at their bottom. A numerical modeling optical properties these structures was performed. demonstrated that they support both plasmon grating resonances, which interaction provides additional enhancement an incident electric field. This can increase surface-enhanced Raman scattering such...

We present the experimental dark-field scattering studies and simulation of plasmonic properties isolated silver nanoislands. The nanoislands were fabricated on a soda- lime glass substrate using silver-sodium ion exchange, subsequent thermal poling annealing processed in hydrogen. morphology was characterized with atomic force microscopy scanning electron microscopy; dimensions 100-180 nm base 80-160 height. measured modeled spectra hemiellipsoidal nanoparticles differing size shape. SPR...

We investigated enhanced by nanoisland metal films Raman scattering from amino acids. It was shown that, despite the sufficient amplification of signal due to nanoislands, identification acids in various biocompatible buffers is difficult interaction and / or with substrate.

We present a study of resonant optical properties paired silver hemispheroids grown on glass substrate using out-diffusion technique combined with thermal poling the glass. Atomic force microscopy was used to characterize morphology nanostructures. Dark-field spectroscopy and numerical simulation were applied coupled nanoparticles (NPs) depending interparticle gap size difference in pair. Raman testing hemispherical NPs showed that they can provide signal enhancement factor exceeding one single NP.

We present a technique to fabricate SERS substrates fully integrated with microfluidic channels. The fabrication of microsized dielectric channels was based on selective wet etching poled/unpoled silicate glass while silver nanoisland film grown the bottom via out-diffusion technique. Different combinations steps were studied optimize channels' depth, formation metal nanoislands and roughness bottom.