A5024665734- Gold and Silver Nanoparticles Synthesis and Applications
- GaN-based semiconductor devices and materials
- ZnO doping and properties
- Advanced biosensing and bioanalysis techniques
- Biosensors and Analytical Detection
- Quantum Dots Synthesis And Properties
- Semiconductor materials and devices
- Ga2O3 and related materials
- Spectroscopy Techniques in Biomedical and Chemical Research
- Metal and Thin Film Mechanics
- Copper-based nanomaterials and applications
- Semiconductor Quantum Structures and Devices
- Chalcogenide Semiconductor Thin Films
- Nanoporous metals and alloys
- Carbon Dioxide Capture Technologies
- Protein Interaction Studies and Fluorescence Analysis
- Anodic Oxide Films and Nanostructures
- Nanotechnology research and applications
- Surface Modification and Superhydrophobicity
- Thin-Film Transistor Technologies
- Extracellular vesicles in disease
- Nanocluster Synthesis and Applications
- Laser-induced spectroscopy and plasma
- Surfactants and Colloidal Systems
- Thermal properties of materials
Polish Academy of Sciences
2011-2019
Institute of High Pressure Physics
2011-2019
We fabricated a Surface Enhanced Raman Scattering (SERS)-active surface based on photo-etched and Au-coated GaN. The highest enhancement factor (EF) in SERS high reproducibility of spectra were obtained from surfaces covered with bunched nanopillars which produced by relatively long defect-selective photo-etching. exhibited enhancements the order 2.8 × 106 for malachite green isothiocyanate (MGITC) 2 p-mercaptobenzoic acid (PMBA). These factors comparable to those conventional substrates,...
The main aim of this work was developing a novel technology for producing platforms surface enhanced Raman scattering (SERS) measurements on photoetched (nanostructured) GaN with Au–Cu thin film as plasmonic layer. Dealloying deposited films gives very stable and SERS-active platforms. Influence percentage copper in the alloyed layer SERS enhancement factor (EFSERS) examined. were performed using pyridine 4-mercaptobenzoic acid. Corresponding covered Au Au–Ag layers used reference. It also...
In this communication, we show that chemical modifications of etched GaN (with different morphological features) through treatment with trichlorododecylsilane or sputtering nano-Au films followed by covalent binding 1-dodecanethiol strongly affect surface water repellency characteristics. Binding to Au-coated whiskers results in crystals becoming superhydrophobic the contact angles approaching 150°. For a single type morphology, pairwise comparison angle values trichlorododecylsilane- and...
The ability to self-assemble nanosized ligand-stabilized metal oxide or semiconductor materials offers an intriguing route engineer nanomaterials with new tailored properties from the disparate components. We describe a novel one-pot two-step organometallic approach prepare ZnO nanocrystals (NCs) coated deprotonated 4-(dodecyloxy)benzoic acid (i.e., X-type liquid-crystalline ligand) as model LC system (termed ZnO-LC1 NCs). Langmuir and Langmuir-Blodgett films of resulting hybrids are...
The homoepitaxial growth of $m$-plane $(1\overline{1}00)$ GaN was investigated by plasma-assisted molecular beam epitaxy under nitrogen-rich conditions. surface morphologies as a function sample miscut were studied, providing evidence for strong anisotropy that is consequence the Ga adatom diffusion barriers on recently calculated ab initio [Lymperakis and Neugebauer, Phys. Rev. B 79, 241308(R) (2009)]. We found substrate toward $[000\overline{1}]$ implies step flow...
Bovine serum albumin (BSA) is often employed as a proteinaceous component for synthesis of luminescent protein-stabilized gold nanoclusters (AuNC): intriguing systems with many potential applications. Typically, the formation BSA-AuNC conjugate occurs under strongly alkaline conditions. Due to sheer complexity intertwined chemical and structural transitions taking place upon formation, state enveloping AuNCs remains poorly characterized. Here, we study conformational properties BSA bound...
We report on the activation of CO2 by well-defined alkylzinc hydroxide (tBuZnOH)6 in absence and presence tBu2Zn as an external proton acceptor. The slight modifications reaction systems involving organozinc precursors enable control products with high selectivity leading to isolation mesoporous solid based ZnCO3 nanoparticles or unprecedented discrete carbonate [(tBuZn)2(μ5-CO3)]6 cluster Zn-C bond intact, respectively.
A novel inorganic nanocomposite material, called BOA, which has the form of small building blocks composed gold nanoparticles embedded in a polyoxoborate matrix, is presented. It demonstrated that cotton wool decorated with BOA displays strong antibacterial activity toward both Gram-positive and -negative bacteria strains. Importantly, modified does not release any toxic substances, are killed upon contact fibers coated BOA. Toxicity tests show nanocomposite–in spite its antiseptic...
We report an innovative application of a true "bottom-up" approach for preparation functional material. Three consecutive self-assembly steps were utilized formation complex surface enhanced Raman spectroscopy (SERS) platform. First the Langmuir–Blodgett technique was used to deposit gold nanoparticles on solid substrate. Thus prepared surfaces afterward as substrates in chemical vapor deposition process gallium nitride (GaN) nanowire growth. On such scaffolding, third step material...
The fabrication procedure of efficient surface enhanced Raman scattering (SERS) platforms is demonstrated based on reproducibly photo-etched GaN epitaxial layers covered by a thin Au-Ag layer and subjected to partial de-alloying. Using gold-rich Au57Ag43 alloy (70/30 wt. %), it possible preserve about 19 at. % silver in the layer, even after etching nitric acid for up 24 h. A large enhancement signal from test 4-mercaptobenzoic molecules attached such porous metal obtained due presence high...
Controlled patterning and formation of nanostructures on surfaces based self-assembly is a promising area in the field "bottom-up" nanomaterial engineering. We report net-like structures gold nanoparticles (Au NPs) matrix liquid crystalline amphiphile 4'-n-octyl-4-cyanobiphenyl at air-water interface. After initial compression to least 18 mN m(-1), decompression Langmuir film mixture containing both components results structures. The average size unit cell net easily adjustable by changing...
Abstract It is suggested that final bowing of {0001} planes in free standing GaN depends mostly on the nucleation mechanism at beginning growth presented approach. Typical process this study, includes formation pyramidal islands through openings mask, their semi‐polar faces, coalescence, smoothening layer and finally, bulk c‐plane crystal. The initial containing large fraction material grown faces strongly n‐type (n > 10 19 cm ‐3 ) due to enhanced incorporation oxygen. In contrast,...
Abstract In this paper the growth and physical properties of HNPS‐GaN crystallized in “feed‐seed” configuration is described. The idea based on conversion free standing HVPE‐GaN crystals to HNPS‐GaN. influence c‐plane bowing initial substrate quality, rate, mode from solution analyzed.
Homoepitaxial growth of m-plane GaN (11¯00) as a function substrate miscut and temperature was studied by plasma assisted molecular beam epitaxy (PAMBE). The authors demonstrate that it is possible to obtain high-quality on the under nitrogen-rich conditions at 730 °C. This in contrast c-plane where three-dimensional mode observed same conditions. They find strong anisotropy describe surface morphology dependence sample direction. results indicate introducing toward ⟨112¯6¯⟩ one may expect...
Chemical etching of gallium nitride (GaN) crystals produces various morphological patterns such as 'nanowhiskers'. Due to the microscopic roughness etched GaN surfaces may be converted via further chemical functionalization into superhydrophobic materials or substrates for surface-enhanced Raman scattering (SERS). Here, properties Au-sputtered nanowhiskers functionalized with two mixed thiols: aliphatic non-polar 1-butanethiol (C4SH) and aromatic ionizable 4-mercaptobenzoic acid (4-MBA) are...