Browsing Zinātniskie raksti (CFI) / Scientific articles by Title
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Hybrid Tribo-Piezo-Electric Nanogenerator with Unprecedented Performance Based on Ferroelectric Composite Contacting Layers
(American Chemical Society, 2019)It was recently reported that more efficient triboelectric nanogenerator (TENG)-like devices can be prepared using inversely polarized ferroelectric films made of same material as the contacting layers. In the present work, ... -
Hydrogen from industrial aluminium scraps: Hydrolysis under various conditions, modelling of pH behaviour and analysis of reaction by-product
(Elsevier, 2023)The study explores the feasibility of utilizing aluminium scrap waste from the construction industry for hydrogen production via hydrolysis. Specifically, the study involves a primary analysis of aluminium scrap waste and ... -
Hydrothermal Synthesis and Properties of Yb3+/Tm3+ Doped Sr2LaF7 Upconversion Nanoparticles
(MDPI, 2023)We report the procedure for hydrothermal synthesis of ultrasmall Yb3+/Tm3+ co-doped Sr2LaF7 (SLF) upconversion phosphors. These phosphors were synthesized by varying the concentrations of Yb3+ (x = 10, 15, 20, and 25 mol%) ... -
Identification of Active Sites for Oxygen Reduction Reaction on Nitrogen- and Sulfur-Codoped Carbon Catalysts
(American Chemical Society, 2019)Nitrogen- and sulfur-codoped carbon catalysts were prepared as electrocatalytic materials for the oxygen reduction reaction (ORR). Herein, we propose a novel and effective one-pot synthetic approach to prepare a NS-doped ... -
Identifying iron-bearing nanoparticle precursor for thermal transformation into the highly active hematite photo-fenton catalyst
(MDPI AG, 2020)The hematite photo-Fenton catalysis has attracted increasing attention because it offers strong oxidation of organic pollutants under visible light at neutral pH. In the present work, aqueous synthesis of hematite photo-Fenton ... -
Impact of gadolinium on the structure and magnetic properties of nanocrystalline powders of iron oxides produced by the extraction-pyrolytic method
(MDPI AG, 2020)Interest in magnetic nanoparticles is primarily due to their practical use. In this work, for the production of nanocrystalline powders of pure and gadolinium doped iron oxides, the extraction-pyrolytic method (EPM) was ... -
The Impact of Graphene in Na2FeP2O7/C/Reduced Graphene Oxide Composite Cathode for Sodium-Ion Batteries
(MDPI, 2023)This study presents a thorough investigation of Na2FeP2O7 (NFP) cathode material for sodium-ion batteries and its composites with carbon and reduced graphene oxide (rGO). Our findings demonstrate that rGO sheets improve ... -
Impact of Helium Ion Implantation Dose and Annealing on Dense Near-Surface Layers of NV Centers
(MDPI, 2022)The implantation of diamonds with helium ions has become a common method to create hundreds-nanometers-thick near-surface layers of NV centers for high-sensitivity sensing and imaging applications; however, optimal ... -
The impact of temperature on electrical properties of polymer-based nanocomposites
(American Institute of Physics, 2020)The paper discusses the results of temperature studies of polymer-based nanocomposites obtained by incorporating multi-walled carbon nanotubes in thin layers of poly(3,4-ethylenedioxythophene):poly(4-styrenesulfonate), ... -
Impact of thermal treatment on the surface of na0.5bi0.5tio3-based ceramics
(Multidisciplinary Digital Publishing Institute (MDPI), 2021)Thermal etching is a widely accepted surface treatment method for studying microstructure in Na0.5Bi0.5TiO3-based compositions. Surprisingly, besides the flat pattern of grains (suitable for evaluating ceramics’ microstructure), ... -
Improvement of Heat Dissipation in Ag/Ni Substrates for Testing Cu-TiO2/TiO2-Modified Filters Using SERS Spectroscopy
(MDPI, 2023)Surface-enhanced Raman scattering (SERS) spectroscopy is used to investigate a composition of wash swabs from the Cu-TiO2/TiO2-modified filters with disinfecting ability. Macroporous Si chips coated with conformal 800 nm ... -
Improvement of β-SiC Synthesis Technology on Silicon Substrate
(MDPI, 2023)This article presents an enhanced method for synthesizing β-SiC on a silicon substrate, utilizing porous silicon as a buffer layer, followed by thermal carbide formation. This approach ensured strong adhesion of the SiC ... -
In Situ Regeneration of Copper-Coated Gas Diffusion Electrodes for Electroreduction of CO2 to Ethylene
(Multidisciplinary Digital Publishing Institute (MDPI), 2021)A key challenge for carbon dioxide reduction on Cu-based catalysts is its low faradic efficiency (FE) and selectivity towards higher-value products, e.g., ethylene. The main factor limiting the possibilities of long-term ... -
In Situ Study of Zinc Peroxide Decomposition to ZincOxide by X-Ray Absorption Spectroscopy and ReverseMonte Carlo Simulations
(Wiley, 2022)The Zn K-edge X-ray absorption spectroscopy is used to investigate in situ the decomposition of zinc peroxide ((Formula presented.)) to zinc oxide (ZnO). Principal component and linear combination analyses of the extended ... -
Influence of "productive" Impurities (Cd, Na, O) on the Properties of the Cu2ZnSnS4Absorber of Model Solar Cells
(Walter de Gruyter, 2021)Abstract The study focuses on the optical properties of the CZTS multicomponent semiconductor absorber with 3 % "production"impurities of Cd, Na, O within the framework of the density functional theory using the generalized ... -
Influence of Au, Ag, and Cu Adatoms on Optical Properties of TiO2 (110) Surface: Predictions from RT-TDDFT Calculations
(MDPI, 2022)In this paper, real-time time-dependent density-functional theory (RT-TDDFT) calculations are performed to analyze the optical property and charge transitions of a single noble metal atom deposited on rutile TiO2 (110) ... -
Influence of cation order on the dielectric properties of (1 - x)Pb(Sc0:5Nb0:5)O3-xPb(Yb0:5Nb0:5)O3ceramics
(Walter de Gruyter, 2021)Ceramic lead niobates and their solid solutions (1 - x)Pb(Sc0:5Nb0:5)O3 - xPb(Yb0:5Nb0:5)O3 were synthesized by solid state reactions from oxides. The structure of investigated samples was characterized by X-ray diffraction ... -
Influence of Heat Treatment and High-Pressure Torsion on Phase Transformations in TiZrHfMoCr High-Entropy Alloy
(MDPI, 2023)The study focused on a 21.99 at.%Ti–22.49 at.%Zr–20.35 at.%Hf–17.45 at.%Mo–17.73 at.%Cr). Analytical techniques such as X-ray diffraction, scanning electron microscopy as well as X-ray absorption spectroscopy were employed ... -
Influence of Nb-doping on the local structure and thermoelectric properties of transparent TiO2:Nb thin films
(Elsevier Ltd, 2020)Transparent n-type niobium-doped titanium dioxide thin films (TiO2:1.5 at.%Nb) with pronounced thermoelectric properties were produced from a composite Ti:Nb target by reactive magnetron sputtering. The thin films were ... -
Influence of organic material and sample parameters on the surface potential in Kelvin probe measurements
(Springer New York LLC, 2019)Scanning Kelvin probe is a method for material surface studies. It is used to determine the work function of metals. In the case of organic semiconductors, the measured surface potential is considered to be the Fermi level ...