A5075243015- Gas Sensing Nanomaterials and Sensors
- ZnO doping and properties
- Gold and Silver Nanoparticles Synthesis and Applications
- Plasmonic and Surface Plasmon Research
- Acoustic Wave Resonator Technologies
- Metamaterials and Metasurfaces Applications
- Catalytic Processes in Materials Science
- Advanced Chemical Physics Studies
- Quantum Dots Synthesis And Properties
- Nanocluster Synthesis and Applications
- Transition Metal Oxide Nanomaterials
- Ga2O3 and related materials
- Copper-based nanomaterials and applications
- Analytical Chemistry and Sensors
- nanoparticles nucleation surface interactions
- Thermal Radiation and Cooling Technologies
- Advanced Memory and Neural Computing
- Electrocatalysts for Energy Conversion
- Catalysis and Oxidation Reactions
- Underwater Acoustics Research
- Electronic and Structural Properties of Oxides
- Speech and Audio Processing
- Photonic Crystals and Applications
- Optical Wireless Communication Technologies
- Mercury impact and mitigation studies
Southern Federal University
2010-2024
KU Leuven
2014-2021
Moscow Institute of Physics and Technology
2019-2021
Laboratoire de physique des Solides
2014-2016
The nonlinear absorption of Ag atomic clusters and nanoparticles dispersed in a transparent oxyfluoride glass host has been studied. as-prepared glass, containing 0.15 atom % Ag, shows an band the UV/violet attributed to presence amorphous nanoclusters with average size 1.2 nm. Upon heat treatment coalesce into larger that show surface plasmon visible. Open aperture z-scan experiments using 480 nm nanosecond laser pulses demonstrated nonsaturated saturated large indices for nanoparticles,...
Abstract A major drawback of state‐of‐the‐art proton exchange membrane fuel cells is the CO poisoning platinum catalysts. It known that reduced if alloys are used, but underlying mechanism therefore still under debate. We study influence dopant atoms on adsorption small clusters using mass spectrometry experiments and density functional calculations. significant reduction in reactivity for Nb‐ Mo‐doped attributed to electron transfer from those highly coordinated dopants Pt concomitant lower...
Bulk SiO2-PbF2 oxyfluoride glasses co-doped with dispersed luminescent Ag nanoclusters and Tm3+ ions have been prepared by conventional melt-quenching method. Luminescence from 400 to 900 nm has excited in this glass UV light 340 nm. The potential for application as a low cost phosphor Hg-free white generation UV-driven devices, flexible monitors down-shifting layers enhanced solar cells. Co-doping Tm3+, which an absorption band 3H6→1D2, affects the tint of total Ag-Tm3+ emission changing...
The effect of Pd doping on the structure and optical absorption small cationic gold clusters is investigated by a combined photodissociation spectroscopy time‐dependent density functional theory study Au n + Ar p PdAu ‐1 ( = 4,5; 0,1). While pure are planar, Pd‐doped 3D. UV–visible studied in 2.0–4.7 eV photon energy range, allowing observation previously unreported bands for 4 Ar. oscillator strength transitions dramatically reduced upon incorporating atom Ar, while this less pronounced 5...
Photoabsorption spectra of gas phase Aun+ and Aun−1Pd+ (13 ≤ n 20) clusters were measured using mass spectrometric recording wavelength dependent Xe messenger atom photodetachment in the 1.9–3.4 eV photon energy range. Pure cationic gold consisting 15, 17, 20 atoms have a higher integrated optical absorption cross section than neighboring sizes. It is shown that total increases with size palladium doping strongly reduces this for all investigated sizes particular = 14–17 20. The largest...
The thermal radiation from small, laser heated, positively charged niobium clusters has been measured. emitted power was determined by the quenching effect on metastable decay, employing two different experimental protocols. radiative decreases slightly with cluster size and shows no strong size-to-size variations. magnitude is 40–50 keV/s at timescale of several microseconds, which measured crossover time evaporative to cooling.
Core-shell ZnO/ZnMnO nanowires on a-Al2O3 and GaN (buffer layer)/Si (111) substrates were fabricated by pulsed laser deposition using a Au catalyst. Two ZnO targets with Mn content of 10% sintered at 1150 550 °C in order to achieve the domination them paramagnetic MnO2 ferromagnetic Mn2O3 phases, respectively. Cluster mechanism ablation as source possible incorporation secondary phases wire shell is discussed. Raman spectroscopy under excitation an Ar+ revealed broad peak related Mn-induced...
The catalytic activity of metal clusters can be easily tuned by their size, charge state, or the introduction dopant atoms. Here, dopant-, charge- and size-dependent propene adsorption on gold (Au n +) yttrium doped n-1Y+) (n = 4-20) was investigated using combined gas-phase reaction studies density functional theory computations. increased transfer between cluster in cationic considerably enhances binding both pure yttrium-doped species, compared to neutral counterparts, while...
Ultrafast electron-phonon coupling dynamics in ZnO are investigated by degenerate pump-probe reflectivity measurements using near resonant 400 nm light. Because of the below-gap excitation, photocarriers excited primarily from deep levels intrinsic point defects. At least six coherent phonon modes, including two E(2) modes and their combination, longitudinal optical (LO) mode its overtone (2LO), observed. Unlike previous Raman studies 325 light, intensity polar LO phonons is only moderately...
Phase change metasurfaces based on VO2, which are pre-heated with electric current and optically addressed by projected structured light hologram, considered to become a new paradigm in programmed THz/middle IR flat optics. Macroscopic quasi-homogeneous arrays of Au nanoparticles show large near absorption significant photothermal effect capable boosting light-triggered switching VO2 be carefully examined. We propose approach simultaneously probe the altered temperature conductivity hybrid...
A new approach to enhance the sensitivity of existing SAW UV-visible photo-detectors based on monitoring multiple reflections acoustic waves in Fourier transform frequency response (S21) is demonstrated. By using this concept, it possible monitor light a wide intensity range from very high ultralow. We present strategy obtain an ultrafast UV photo-detector with millisecond by tuning deposition conditions ZnO film and multiple-reflections concept.
The combination of X-ray spectroscopy methods complemented with theoretical analysis unravels the coexistence paramagnetic and antiferromagnetic phases in Zn0.9Mn0.1O shell deposited onto array wurtzite ZnO nanowires. is crystalline orientation toward growth axis, as demonstrated by linear dichroism. EXAFS confirmed that more than 90% Mn atoms substituted Zn while a fraction secondary was below 10%. value manganese spin magnetic moment estimated from Kβ emission to be 4.3 μB which close for...
We study the enhancement of fluorescence an photoluminescence by large homogeneous arrays plasmon coupled 5-8 nm Au and Ag nanoparticle separated distances less than 10 nm. A red shift major "symmetric" mode near 780 nm, additional "anti-symmetric" centered 310 evidence coupling in particle arrays. The systems were found to be effective fluorescence/photoluminescence processes.
Infrared (IR) and terahertz plasmons in two-dimensional (2D) materials are commonly excited by metallic or dielectric grating couplers with deep-submicron features fabricated e-beam lithography. Mass reproduction of such gratings at macroscopic scales is a labor-consuming expensive technology. Here, we show that localized graphene can be generated on based randomly oriented particle-like nanorods (NRs) close proximity to layer. We monitor the excitation indirectly tracking changes...
A tunable high-Q surface acoustic wave (SAW) resonator in the form of several parallel-connected interdigital transducers loaded on a varying capacitance lithium niobate substrates was developed and studied. The working frequency range 90–2450[Formula: see text]MHz. method calculating such resonators, considering losses metal film as well due to propagation SAWs transformations into bulk waves is proposed. Such design allows one obtain quality factor over 5000 2400–2483[Formula: resonant...