A5090816672- Supercapacitor Materials and Fabrication
- Electrocatalysts for Energy Conversion
- Quantum, superfluid, helium dynamics
- Fuel Cells and Related Materials
- Hydrogen Storage and Materials
- Advancements in Battery Materials
- Advanced Battery Materials and Technologies
- Phase Equilibria and Thermodynamics
- Graphene research and applications
- Boron and Carbon Nanomaterials Research
- Conducting polymers and applications
- Catalytic Processes in Materials Science
- Advanced materials and composites
- Diamond and Carbon-based Materials Research
- Electrospun Nanofibers in Biomedical Applications
- Analytical Chemistry and Sensors
- Advanced Sensor and Energy Harvesting Materials
- Advanced NMR Techniques and Applications
- Nuclear Physics and Applications
- Electrochemical Analysis and Applications
- Electric Power Systems and Control
- NMR spectroscopy and applications
- Catalysis and Hydrodesulfurization Studies
- Magnetic and transport properties of perovskites and related materials
- Electronic and Structural Properties of Oxides
University of Tartu
2017-2025
Strong confinement of hydrogen is important for adsorption-based storage solutions, which are vital the transition toward a hydrogen-based economy. The dynamics adsorbed in high-porosity TiC-derived carbon with relatively well-stacked graphenic layers carbide-derived investigated situ inelastic and quasi-elastic neutron scattering methods. Both para-ortho rotational elastic incoherent factor investigated. Hydrogen translationally bound at temperatures 20-80 K. At 50 80 K, exhibits localized...
Antibacterial drug-loaded electrospun nano- and microfibrous dressings are of major interest as novel topical drug delivery systems in wound care. In this study, chloramphenicol (CAM)-loaded polycaprolactone (PCL) PCL/poly(ethylene oxide) (PEO) fiber mats were characterized terms morphology, distribution, physicochemical properties, release, swelling, cytotoxicity, antibacterial activity. Computational modeling together with analysis helped to elucidate possible interactions between the...
Influence of specific surface area (SDFT), total pore volume (Vtot) and other porosity characteristics on the electrochemical parameters power density two electrode electric double layer capacitors based 1 M 3-ethyl-methylammonium tetrafluoroborate (Et3MeNBF4) solution in acetonitrile 1-ethyl-3-methylimidazolium (EtMeImBF4) has been analysed. The size distribution data calculated from nitrogen, CO2 Ar adsorption isotherms using mainly Carbon 2D non-local functional theory for heterogeneous...
Surface porosity of individual electrospun polymeric fibers provides interesting means for controlling fiber behavior different biomedical applications. In this study porous polycaprolactone (PCL) microfibers were obtained by electrospinning PCL solution in tetrahydrofuran/dimethyl sulfoxide (DMSO) and chloroform/DMSO at high relative humidity (65%). No pores formed low (19%). Fibers with surface diameter revealed drug release favoring the from compared to non-porous nanofibers microfibers....
This study highlights the advantages of using wide-angle X-ray scattering (WAXS) and small-angle neutron (SANS) methods to analyse turbostratic D-glucose-derived hard carbons (GDCs) over a wide range length scales. It demonstrates reasons for superior performance (HCs) pyrolysed at 1100°C compared those 700°C, 1000°C, or 1400°C in sodium-ion batteries (SIBs). Twelve WAXS thirteen SANS structural parameters were simultaneously determined HCs. The investigation incorporates WAXS-derived...
The influence of the synthesis conditions on formation porous and graphitic structure carbon materials was investigated Mo2C-derived synthesized at different temperatures (Tsyn from 700 to 1000 °C). Contrast matched small-angle neutron scattering method used obtain explicit information about pore wall carbons. It found that carbons formed lower Tsyn exhibit prevalently nano-scale cylindrical geometry an increase in promotes slit-like structures. Additionally, partial contrast matching used,...
The self-diffusion mechanisms for adsorbed H2 in different porous structures are investigated with situ quasi-elastic neutron scattering method at a temperature range from 50 K to 100 and various loadings. of the carbon materials have been characterized by sorption analysis four gases results correlated previous in-depth small-angle method. Thus, an investigation discussing effect pore shape size on nature is performed. It shown that nanometer-scale pores self-diffusing two distinguishable...
Simple and modified synthesis route for preparation of Fe-N/C type oxygen reduction reaction (ORR) catalysts has been worked out discussed. The significant effect the N precursor chemical composition on ORR activity in 0.1 M KOH HClO4 electrolyte solutions demonstrated. half-wave potential values increased following order: C(SiC) < Fe + Urea/C EDTA/C DIPO/C ≤ Phen/C Bipyr/C both studied. Molar ratio Fe:N content change catalyst was found to be negligible. Noticeable observed after acid...
Quick characterization methods to determine the structure of carbon materials are sought after for a wide array technical applications. In this study we present combined analysis carbide-derived carbons (CDCs) with Raman spectroscopy and wide-angle X-ray scattering (WAXS) methods. We optimal deconvolution method be used detailed data CDCs comparison corresponding WAXS results is made. For broad set both showed that average graphene layer extent increases synthesis temperature CDC, while...
For the first time, a novel peat-derived carbon (PDC) was used to synthesize an active non-platinum group metal type catalyst for oxygen reduction reaction (ORR) and evolution (OER). The obtained exhibited smaller specific surface area more graphitic compared synthesized identically but using carbide-derived (CDC) instead of PDC. Due organic nature peat, PDC contained numerous additives. In 0.1 M KOH, both CDC-based catalysts displayed ORR activity comparable Pt/Vulcan. Additionally, equally...
Carbons are important in a multitude of applications, and thus, the reversible control carbon structures is high interest. Here we report formation graphitic with three distinct interlayer distances case two carbide-derived carbons (CDCs) loaded under hydrogen pressure observed situ neutron scattering methods. The these determined diffraction brought forth by confinement H2 porous structure when temperature, T, increased from T = 20 K–50 K loading 68 mbar to 10 bar. desorbing causes increase...
Understanding the processes guiding confinement of adsorbed H2 in different porous structures is vital for development adsorbents effective cryo-adsorptive storage systems. Quasi-elastic neutron scattering (QENS) applied over a wide range timescales (0.2 ps – 150 ps) to determine self-diffusion mechanisms carbide (synthesized from TiC via sol-gel method) derived carbon (sol-gel TiC-CDC) adsorbent with hierarchical structure. The bulk and structure characterized by gas adsorption, Raman...
In this study, several peat-derived carbons (PDC) were synthesized using various carbonization protocols. It was found that depending on the method, with very different surface morphologies, elemental compositions, porosities, and oxygen reduction reaction (ORR) activities obtained. Five used as carbon supports to synthesize Co-N/PDC catalysts, five ORR catalysts acquired. The analysis revealed a higher nitrogen content, number of oxide defects, specific area lead activity in acidic...
Microporous carbon materials are promising for hydrogen storage due to their structural variety, high specific surface area, large pore volume and relatively low cost. Carbide-derived carbons highly valued as model because porous structure is fine-tuned through the choice of precursor carbide synthesis route. This study investigates H 2 adsorption in three derived with well-defined pores size distributions quasi- inelastic neutron scattering methods. Concerning previous studies, a wider...
Influence of specific micropore-, mesopore and total surface areas pore volumes other porosity characteristics on the electrochemical parameters power density devices will be discussed [1-3]. Many ionic liquids (EtMeImBF 4 , Et B(CN ) etc.) organic (Et 3 MeNBF NBF PrNBF inorganic salts (LiBF NaBF LiClO NaClO LiPF 6 NaPF Rb 2 SO Li Na LiI, NaI, NaBr, LiBr, LiCl, NaCl, CsBF Cs carborane, based electrolytes in various solvents (H O, acetonitrile, ethyl methyl carbonate, propylene diethyl...
Abstract Research-based education is a long-standing tradition at the University of Tartu (UT). Basic knowledge electrochemistry and principles developing electrochemical devices have been taught implemented UT since 1960. For instance, during then, self-made alkaline electrolysers were used to generate hydrogen. The hydrogen was further purified saturate aqueous non-aqueous electrolytes. fundamental research has formed solid background on which development supercapacitors Na + -ion or Li...
Abstract The electrochemical and crystalline structure of mixed ionic‐electronic conductive La 0.75 Sr 0.25 Cr 0.5 Mn 0.3 Ni 0.2 O 3–δ (LSCMN) electrode in porous scandia ceria stabilized zirconia (ScCeSZ) electrolyte matrix during the first 140 h has been studied an operando XRD experiment. Intense degradation performance a fuel cell as well electrolysis modes observed. However, mechanism was seen to be different for two operation modes. formation new ceramic phase observed on surface using...
Using different carbonization protocols, five peat derived carbon materials were synthesized. These carbons have very surface morphology confirmed by HR-SEM and porosities pore size distributions obtained N 2 sorption method. The ORR activity of the also differs significantly in 0.1 M HClO 4 solution. Additionally, co-doping with cobalt nitrogen enhanced their catalytic considerably. most active catalyst was achieved using support where dry milled mixed ZnCl pyrolyzed Ar for h at 700 °C....
The two different diffusion mechanisms for adsorbed H2 in porous structures are investigated with situ quasi-elastic neutron scattering method at a temperature range from 50 K to 100 and various loadings. of the carbon materials have been characterized by sorption analysis four gases results correlated previous in-depth small-angle method. Thus, an investigation discussing effect pore shape size on nature is performed. It shown that nanometer-scale pores diffusing distinguishable timescales....
Understanding the processes guiding confinement of adsorbed H2 in different porous structures is vital for development adsorbents effective cryo-adsorptive storage systems. Quasi-elastic neutron scattering (QENS) applied over a wide range timescales (0.2 ps – 150 ps) to determine self-diffusion mechanisms carbide (synthesized from TiC via sol-gel method) derived carbon (sol-gel TiC-CDC) adsorbent with hierarchical structure. The bulk and structure characterized by gas adsorption, Raman...