Published references
|
These publications have a reference to ProboStat™ or other NORECS products
All 1-25 26-50 51-75 76-100 101-125 126-150 151-175 176-200 201-225 226-250 251-275 276-300 301-325 326-350 351-375 376-400 401-425 426-450 451-475 476-500 501-525 526-550 551-575 576-600 601-625 626-650 651-675 676-Synthesis and Triple Conductive Properties of Ba and Fe Co-Doped Sr2TiO4 Based Layered Perovskite: (BaxSr2-x) (Ti0.9Fe0.1)O4-δ (X= 0.05, 0.10)
ID=639| Authors |
|
| Source |
Key Engineering Materials
Volume: 888,
Pages: 37-42 Time of Publication: 2021 |
| Abstract | This study investigated the effects of Ba substitution on protonic conductive properties in the Fe doped Sr2TiO4 layered perovskite. We synthesized sintered samples of (BaxSr2-x)(Ti0.90Fe0.10)O4-δ (x= 0.05, 0.10) (BSTF05, BSTF10). The result of X-ray diffraction suggests that solid solute limitation of Ba is between x= 0.05 and 0.10. BSTF05 at 600 °C shows proton and oxide-ion conductivities as well as elecronic conductivity. It means that BSTF05 is a triple conductor at 600 °C under oxidation atmosphere. The proton conductivities in BSTF05 are lower than that in Ba un-doped Sr2(Ti0.9Fe0.1)O4-δ evaluated in our previous work, suggesting that the effect of the Ba substitution on proton defect generation is small. The redox reaction of Fe ions is more important for creation of proton defects in the layered perovskites. |
| Remark |
https://doi.org/10.4028/www.scientific.net/KEM.888.37 Link |
Electrochemical, Thermal, and Structural Features of BaF2–SnF2 Fluoride-Ion Electrolytes
ID=638| Authors |
|
| Source |
J. Phys. Chem. C
Volume: 125,
Issue: 23,
Pages: 12568–12577 Time of Publication: 2021 |
| Abstract | Fluoride-ion-conducting compounds are key materials for solid electrolytes in all-solid-state fluoride shuttle batteries (FSBs) and widely regarded as promising rechargeable batteries. However, their ionic conductivities are still insufficient to allow room-temperature operation. Particularly, the transportation of F ions through solid-state ionic devices is yet to be fully understood. We studied the electrochemical, thermal, and structural features of BaF2–SnF2 solid electrolytes by means of AC impedance, differential scanning calorimetry, X-ray diffraction, and neutron diffraction experiments. The substitution of Ba by Sn atoms increased the electrical conductivity of BaF2–SnF2 to 107–109 times that of BaF2; particularly, (BaF2)0.47(SnF2)0.53 exhibited the highest electrical conductivity (σ = 4.1 × 10–3 S/cm at room temperature) with the lowest activation energy (Ea = 17.9 kJ/mol). Structural analysis revealed that (BaF2)0.47(SnF2)0.53 consists of a tetragonal structure (T-phase) and residual amounts of the cubic structure (C-phase). The T-phase could be refined on the basis of a [−SnSnMMSnSn−]-layered structure (M = BaxSn1–x) with three nonequivalent fluorine sites: F1, F2, and F3. The anisotropic displacement of F3 was more pronounced toward F1; thus, the “–F1–F3–F1–” zigzag network between the M and Sn layers plays a key role in two-dimensional fast F-ion diffusion. |
| Remark |
https://doi.org/10.1021/acs.jpcc.1c03326 Link |
Effect of ball-milling on the phase formation and enhanced thermoelectric properties in zinc antimonides
ID=637| Authors |
|
| Source |
Materials Science and Engineering: B
Volume: 271,
Pages: 115274 Time of Publication: 2021 |
| Abstract | We report the phase formation mechanism and the enhanced thermoelectric properties of zinc antimonide (ZnSb) thermoelectric material. The phase pure ZnSb thermoelectric material is achieved using high-energy ball milling of Zn and Sb in a shorter span of time. The ZnSb phase formation is explained by the kinetic energy transferred to the powders during milling for the solid-state reaction between Zn and Sb to form the desired ZnSb phase. The repeatability in transport properties up to three thermal cycles corroborates the thermal stability of the processed samples. The thermoelectric figure of merit obtained at 600 K is ~ 0.76 for the processed phase pure ZnSb sample, the highest value in binary ZnSb reported so far. Our results address the ZnSb phase evolution in a shorter milling time and the enhanced thermoelectric properties of the ZnSb materials. The observations will help to scale up the processing of high-performance ZnSb thermoelectric materials. |
| Keywords | Zinc antimonide; Thermoelectric materials; Ball milling; Phase formation kinetics; X-ray diffraction; Figure of merit |
| Remark |
https://doi.org/10.1016/j.mseb.2021.115274 Link |
Enhanced activity of catalysts on substrates with surface protonic current in an electrical field – a review
ID=636| Authors |
|
| Source |
Chem. Commun.
Volume: 57,
Pages: 5737 Time of Publication: 2021 |
| Abstract | It has over the last few years been reported that the application of a DC electric field and resulting current over a bed of certain catalyst-support systems enhances catalytic activity for several reactions involving hydrogen-containing reactants, and the effect has been attributed to surface protonic conductivity on the porous ceramic support (typically ZrO2, CeO2, SrZrO3). Models for the nature of the interaction between the protonic current, the catalyst particle (typically Ru, Ni, Co, Fe), and adsorbed reactants such as NH3 and CH4 have developed as experimental evidence has emerged. Here, we summarize the electrical enhancement and how it enhances yield and lowers reaction temperatures of industrially important chemical processes. We also review the nature of the relevant catalysts, support materials, as well as essentials and recent progress in surface protonics. It is easily suspected that the effect is merely an increase in local vs. nominal set temperature due to the ohmic heating of the electrical field and current. We address this and add data from recent studies of ours that indicate that the heating effect is minor, and that the novel catalytic effect of a surface protonic current must have additional causes. |
| Remark | Link |
In situ cofactor regeneration enables selective CO2 reduction in a stable and efficient enzymatic photoelectrochemical cell
ID=635| Authors |
|
| Source |
Applied Catalysis B: Environmental Volume: 296, Pages: 120349 Time of Publication: 2021 |
| Abstract | Mimicking natural photosynthesis by direct photoelectrochemical (PEC) reduction of CO2 to chemicals and fuels requires complex cell assemblies with limitations in selectivity, efficiency, cost, and stability. Here, we present a breakthrough cathode utilizing an oxygen tolerant formate dehydrogenase enzyme derived from clostridium carboxidivorans and coupled to a novel and efficient in situ nicotinamide adenine dinucleotide (NAD+/NADH) regeneration mechanism through interfacial electrochemistry on g-C3N4 films. We demonstrate stable (20 h) aerobic PEC CO2-to-formate reduction at close to 100 % faradaic efficiency and unit selectivity in a bio-hybrid PEC cell of minimal engineering with optimized Ta3N5 nanotube photoanode powered by simulated sunlight with a solar to fuel efficiency of 0.063 %, approaching that of natural photosynthesis. |
| Remark |
https://doi.org/10.1016/j.apcatb.2021.120349 Link |
A high-entropy manganite in an ordered nanocomposite for long-term application in solid oxide cells
ID=634| Authors |
|
| Source |
Nature Communications
Volume: 12
Time of Publication: 2021
|
| Abstract | The implementation of nano-engineered composite oxides opens up the way towards the development of a novel class of functional materials with enhanced electrochemical properties. Here we report on the realization of vertically aligned nanocomposites of lanthanum strontium manganite and doped ceria with straight applicability as functional layers in high-temperature energy conversion devices. By a detailed analysis using complementary state-of-the-art techniques, which include atom-probe tomography combined with oxygen isotopic exchange, we assess the local structural and electrochemical functionalities and we allow direct observation of local fast oxygen diffusion pathways. The resulting ordered mesostructure, which is characterized by a coherent, dense array of vertical interfaces, shows high electrochemically activity and suppressed dopant segregation. The latter is ascribed to spontaneous cationic intermixing enabling lattice stabilization, according to density functional theory calculations. This work highlights the relevance of local disorder and long-range arrangements for functional oxides nano-engineering and introduces an advanced method for the local analysis of mass transport phenomena. |
| Remark | Link |
3D Printing the Next Generation of Enhanced Solid Oxide Fuel and Electrolysis Cells
ID=633| Authors |
|
| Source |
Electronic Supplementary Material (ESI) for Journal of Materials Chemistry A.
Time of Publication: 2020
|
| Remark | Link |
Microstructure and electrochemical behavior of layered cathodes for molten carbonate fuel cell
ID=632| Authors |
|
| Source |
Journal of Power Sources
Volume: 500,
Pages: 229949 Time of Publication: 2021 |
| Abstract | In the present paper, we demonstrate how modifications of the microstructure and the chemical composition can influence the electrochemical behavior of cathodes for molten carbonate fuel cells (MCFCs). Based on our experience, we designed new MCFC cathode microstructures combining layers made of porous silver, nickel oxide or nickel foam to overcome common issues with the internal resistance of the cell. The microstructures of the standard NiO cathode and manufactured cathodes were extensively investigated using scanning electron microscopy (SEM) and porosity measurements. The electrochemical behavior and overall cell performance were examined by means of electrochemical impedance spectroscopy and single-cell tests in operation conditions. The results show that a porous silver layer tape cast onto standard NiO cathode and nickel foam used as a support layer for tape cast NiO porous layer substantially decrease resistance components representing charge transfer and mass transport phenomena, respectively. Therefore, it is beneficial to combine them into a three-layer cathode since it facilitates separation of predominant physio-chemical processes of gas and ions transport in respective layers ensuring high efficiency. The superiority of the three-layer cathode has been proven by low impedance and high power density as compared to standard NiO cathode. |
| Remark | Link |
Influence of Doping on the Transport Properties of Y1−xLnxMnO3+δ (Ln: Pr, Nd)
ID=631| Author |
|
| Source |
Crystals
Volume: 11,
Pages: 510 Time of Publication: 2021 |
| Abstract | It has been documented that the total electrical conductivity of the hexagonal rare-earth manganites Y0.95Pr0.05MnO3+δ and Y0.95Nd0.05MnO3+δ, as well as the undoped YMnO3+δ, is largely dependent on the oxygen excess δ, which increases considerably at temperatures below ca. 300 ◦C in air or O2. Improvement for samples maintaining the same P63cm crystal structure can exceed 3 orders of magnitude below 200 ◦C and is related to the amount of the intercalated oxygen. At the same time, doping with Nd3+ or Pr3+ affects the ability of the materials to incorporate O2, and therefore indirectly influences the conductivity as well. At high temperatures (700–1000 ◦C) and in different atmospheres of Ar, air, and O2, all materials are nearly oxygen-stoichiometric, showing very similar total conduction with the activation energy values of 0.8–0.9 eV. At low temperatures in Ar (δ ≈ 0), the mean ionic radius of Y1−xLnx appears to influence the electrical conductivity, with the highest values observed for the parent YMnO3. For Y0.95Pr0.05MnO3+δ oxide, showing the largest oxygen content changes, the recorded dependence of the Seebeck coefficient on the temperature in different atmospheres exhibits complex behavior, reflecting oxygen content variations, and change of the dominant charge carriers at elevated temperatures in Ar (from electronic holes to electrons). Supplementary cathodic polarization resistance studies of the Y0.95Pr0.05MnO3+δ electrode document different behavior at higher and lower temperatures in air, corresponding to the total conduction characteristics. |
| Remark | Link |
Preparation and characterization of (La,Ca,Sr)(Fe,Co)O3-d cathodes for solid oxide fuel cells
ID=630| Author |
|
| Source |
Time of Publication: 2021
|
| Remark |
Master Thesis Link |
Fabrication of a Silicide Thermoelectric Module Employing Fractional Factorial Design Principles
ID=629| Authors |
|
| Source |
Journal of Electronic Materials volume
Volume: 50,
Pages: 4041–4049 Time of Publication: 2021 |
| Abstract | Thermoelectric modules can be used in waste heat harvesting, sensing, and cooling applications. Here, we report on the fabrication and performance of a four-leg module based on abundant silicide materials. While previously optimized Mg2Si0.3Sn0.675Bi0.025 is used as the n-type leg, we employ a fractional factorial design based on the Taguchi methods mapping out a four-dimensional parameter space among Mnx-εMoεSi1.75−δGeδ higher manganese silicide compositions for the p-type material. The module is assembled using a scalable fabrication process, using a Cu metallization layer and a Pb-based soldering paste. The maximum power output density of 53 μW cm–2 is achieved at a hot-side temperature of 250 °C and a temperature difference of 100 °C. This low thermoelectric output is related to the high contact resistance between the thermoelectric materials and the metallic contacts, underlining the importance of improved metallization schemes for thermoelectric module assembly. |
| Remark | Link |
Ceramic composites based on Ca3Co4−xO9+δ and La2NiO4+δ with enhanced thermoelectric properties
ID=628| Authors |
|
| Source |
Open Ceramics
Volume: 6,
Pages: 100103 Time of Publication: 2021 |
| Abstract | Ceramic composites were produced by combining the oxide materials Ca3Co4−xO9+δ and La2NiO4+δ. Both compounds were characterized by a plate-like crystal shape, but crystal sizes differed by around two orders of magnitude. The composite materials could be successfully prepared by using uniaxial pressing of powder mixtures and pressureless sintering to a porous ceramic. Possible reactions between both materials during sintering were analyzed. The ceramic composites with low amounts of La2NiO4+δ showed enhanced thermoelectric properties, caused by an increasing power factor and simultaneously decreasing thermal conductivity. For the evaluation of the thermoelectric properties, two different types of Ioffe plots were utilized. The maximum figure-of-merit zT at 1073 K was 0.27 for the pure Ca3Co4−xO9+δ as well as for the sample containing 5 wt% La2NiO4+δ. However, the average in the temperature range of 373 K to 1073 K could be increased by 20% for the composite material. |
| Keywords | Calcium cobalt oxide; Composite; Ceramic; Lanthanum nickelate; Reaction sintering; Thermoelectric; Power factor; Figure-of-merit |
| Remark | Link |
Amorphous ZnO modified anatase TiO2 thin films templated by tripropylamine and their electrical properties
ID=627| Authors |
|
| Source |
Thin Solid Films
Volume: 729,
Pages: 138697 Time of Publication: 2021 |
| Abstract | In the present study we report on a low cost synthesis of amorphous ZnO modified anatase TiO2 (40 and 20 mol% ZnO) thin films deposited via sol-gel spin coating technique on glass substrate. The effects of the composition on the structural, morphological and surface chemistry properties were discussed and correlated with the electrical behavior. Thus, by X-ray diffraction and Raman spectroscopy only TiO2 indexed in the anatase crystalline structure was identified without any ZnO characteristic crystalline phase. The surface chemistry assessed by X-ray Photoelectron spectroscopy highlighted the presence of Ti4+ in TiO2 as well as the presence of Zn2+ coordinated in the amorphous ZnO proved by the Auger ZnLMM transition shifted toward lower binding energies. The films are continuous, homogeneous with grain size below 20 nm and exhibit an intergranular porosity, as it was displayed by Scanning Electron Microscopy. The sensor signal towards CO exposure is strongly related to the amount of the ZnO amorphous phase formation. Thus, we found that a higher content of the ZnO amorphous phase leads to a lower sensitivity. The electrical and sensing measurements were performed in the temperature range (room temperature 400 °C), over the range of CO concentrations (0-2000 ppm). The sensor containing 20 mol.% amorphous ZnO exhibits a good sensitivity at ~300 °C for a low CO concentration . |
| Keywords | Amorphous zinc oxide; Titanium dioxide; Mixed oxides; Sol-gel spin coating technique; Electrical conductivity; Carbon monoxide detection |
| Remark | Link |
The Effect of Thin Functional Electrode Layers on Characteristics of Intermediate Temperature Solid Oxide Fuel Cell
ID=626| Authors |
|
| Source |
Russian Journal of Electrochemistry
Volume: 57,
Pages: 97–103 Time of Publication: 2021 |
| Abstract | The thin-film multilayer structure of the membrane-electrode assembly in a solid oxide fuel cell which involves a NiO/ZrO2:Y2O3 anode functional layer and a La0.6Sr0.4CoO3 cathode functional layer and also a bilayer ZrO2:Y2O3/Ce0.9Gd0.1O1.95 electrolyte is formed by magnetron sputtering onto a supporting NiO/ZrO2:Y2O3 anode. The effect of the functional electrode layers involved in the structure of a solid oxide fuel cell on its efficiency is studied. The volt–ampere characteristics of multilayer fuel cells are studied in the temperature range of 800–600°C. It is shown that the inclusion of a thin (600 nm thick) cathode functional layer into the structure of the membrane–electrode assembly enhances the fuel cell efficiency by reducing the polarization losses on electrodes. The maximum power density of the fuel cell with the cathode functional layer is 2290 and 500 mW/cm2 at 800 and 600°С, respectively. The simultaneous presence of anode and cathode functional layers is found to be unwelcome because gives rise to diffusion limitations on the anode. |
| Remark | Link |
Impedance spectroscopy of manganese-doped mixed alkali phosphate glasses
ID=625| Authors |
|
| Source |
Materials Today: Proceedings
Time of Publication: 2021
|
| Abstract | Glassy-compositions in the system 49.95[xNa2O-(1-x)K2O]-0.1MnO2-49.95P2O5 (with x = 0–1 mol%) were elaborated using melt quenching method. The amorphous state of the samples is ensured by the XRD diffraction technique. The electrical properties including dc conductivity, ac conductivity, and electrical modulus were investigated over a large frequency domain at various temperatures. The evolution of the electric conductivity shows a non-linear variation with the composition. It is found that the activation energy is more sensitive to the substitution of the alkali elements and presents a minimum in the intermediate composition (x = 0.5). The non-linearity behavior of the composition dependence of the electrical parameters is a fingerprint of the mixed alkali effect in the glasses under study. The frequency-dependent of the conductivity follows Jonscher’s power law and the correlated barrier hopping mechanism (CBH) was appropriate for the conduction process inside the glasses. In order to avoid the polarization effect due to the electrodes, the electrical modulus formalism is applied to the impedance data. The results obtained show that conduction relaxation is a non-Debye type. |
| Keywords | Phosphate; Glasses; Mixed alkali effect; Electrical conductivity; Relaxation |
| Remark |
https://doi.org/10.1016/j.matpr.2021.03.467 Link |
Metal-Support Interaction and Electrochemical Promotion of Nano- Structured Catalysts for the Reverse Water Gas Shift Reaction
ID=624| Author |
|
| Source |
Time of Publication: 2021
|
| Abstract | ii Abstract The continued release of fossil-fuel derived carbon dioxide (CO2) emissions into our atmosphere led humanity into a climate and ecological crisis. Converting CO2 into valuable chemicals and fuels will replace and diminish the need for fossil fuel-derived products. Through the use of a catalyst, CO2 can be transformed into a commodity chemical by the reverse water gas shift (RWGS) reaction, where CO2 reacts with renewable hydrogen (H2) to form carbon monoxide (CO). CO then acts as the source molecule in the Fischer-Tropsch (FT) synthesis to form a range of hydrocarbons to manufacture chemicals and fuels. While the FT synthesis is a mature process, the conversion of CO2 into CO has yet to be made commercially available due to the constraints associated with high reaction temperature and catalytic stability. Noble metal ruthenium (Ru) has been widely used for the RWGS reaction due to its high catalytic activity, however, several constraints hinder its practical use, associated with its high cost and its susceptibility to deactivation. The doping or bimetallic use of non-noble metals iron (Fe) and cobalt (Co) is an attractive option to lower material cost and tailor the selectivity of the CO2 conversion towards the RWGS reaction without compromising catalytic activity. Furthermore, employing nanostructured catalysts as nanoparticles is a viable solution to further lower the amount of metal used and utilize the highly active surface area of the catalyst. Dispersing nanoparticles on ionically conductive supports/solid electrolytes which contain species like O2-, H+, Na+, and K+, provide an approach to further enhance the reaction. This phenomenon is referred to as metal-support interaction (MSI), allowing for the ions to back spillover from the support and onto the catalyst surface. An in-situ approach referred to as Non-Faradaic Modification of catalytic activity (NEMCA), also known as electrochemical promotion of catalysis (EPOC) is used to in- situ control the movement of ionic species from the solid electrolyte to and away from the catalyst. Both the MSI and EPOC phenomena have been shown to be functionally equivalent, meaning the ionic species act to alter the work function of the catalyst by forming an effective neutral double layer on the surface, which in turn alters the binding energy of the reactant and intermediate species to promote the reaction. The main objective of this work is to develop a catalyst that is highly active and selective to the RWGS reaction at low temperatures (< 400 °C) by employing the MSI and EPOC iii phenomena to enhance the catalytic conversion. The electrochemical enhancement effect will lower energy requirements and allow the RWGS reaction to take place at moderate temperatures. Catalysts composed of Ru, Fe and Co were synthesized through the polyol synthesis technique and deposited on mixed-ionically conductive and ionically conductive supports to evaluate their performance towards the RWGS reaction and the MSI effect. The nano-structured catalysts are deposited as free-standing nanoparticles on solid electrolytes to in-situ promote the catalytic rate through the EPOC phenomenon. Furthermore, Density Functional Theory (DFT) calculations were performed to correlate theory with experiment and elucidate the role polarization has on the binding energy of reactant and intermediate species. The high dispersion of RuFe nanoparticles on ion-containing supports like samarium- doped ceria (SDC) and yttria-stabilized zirconia (YSZ) led to an increase in the RWGS activity due to the MSI effect. A direct correlation between experimental and DFT modeling was established signifying that polarization affected the binding energy of the CO molecule on the surface of Ru regardless of the type of ionic species in the solid electrolyte. The electrochemical enhancement towards the RWGS reaction has been achieved with iron-oxide (FeOx) nanowires on YSZ. The in-situ application of O2- ions from YSZ maintained the most active state of Fe3O4 and FeO towards the RWGS reaction and allowed for persistent-promoted state that lasted long after potential application. Finally, the deposition of FeOx nanowires on Co3O4 resulted in the highest CO2 conversion towards the RWGS reaction due to the metal-oxide interaction between both metals, signifying a self-sustained electro-promoted state. |
| Remark |
Thesis submitted to the University of Ottawa in partial Fulfillment of the requirements for the Degree of Doctor of Philosophy Link |
Versatile four-leg thermoelectric module test setup adapted to a commercial sample holder system for high temperatures and controlled atmospheres
ID=623| Authors |
|
| Source |
Review of Scientific Instruments
Volume: 92,
Pages: 043902 Time of Publication: 2021 |
| Abstract | A high temperature thermoelectric test setup for the NORECS ProboStat™ sample holder cell has been designed, constructed, and tested. It holds four thermoelectric legs of up to 5 × 5 mm2 area each and flexible height, allows various interconnects to be tested, and utilizes the spring-load system of the ProboStat for fixation and contact. A custom stainless steel support tube flushed with water provides the cold sink, enabling large temperature gradients. Thermocouples and electrodes as well as the gas supply and outer tube use standard ProboStat base unit feedthroughs and dimensions. The setup allows for testing in controlled atmospheres with the hot side temperature of up to around 1000 °C and a temperature gradient of up to 600 °C. We demonstrate the test setup on a four-leg Li–NiO/Al–ZnO module with gold interconnects. The comparison between the predicted performance based on individual material parameters and the experimentally obtained module performance underlines the necessity for testing materials in combination, including interconnects. The four-leg setup allows versatile match-screening, performance evaluation, and long-term stability studies of thermoelectric materials in combination with hot and cold side interconnects under realistic operational conditions. |
| Remark | Link |
Crystal structure, dielectric and optical properties of β-Ca3(PO4)2-type phosphates Ca9-xZnxLa(PO4)7:Ho3+
ID=622| Authors |
|
| Source |
Journal of Luminescence
Volume: 236,
Pages: 118083 Time of Publication: 2021 |
| Abstract | A series of new phosphates Ca9-xZnxLa(PO4)7:Ho3+ with the β-Ca3(PO4)2-type structure was synthesized by the solid state route. An intense near infra-red (NIR) emission according to intraconfigural 4f-4f transitions of Ho3+ ions 5I7 – 5I8 (~2 μm) and 5I6 – 5I8 (~1.156 μm) was observed. The obtained phases were studied by a combination of methods including synchrotron powder X-ray diffraction, dielectric spectroscopy, second harmonic generation, differential scanning calorimetry, luminescence spectroscopy. The structure of Ca8ZnLa(PO4)7 was refined by the Rietveld method in centrosymmetric space group Rc. The Ca2+ → Zn2+ substitution in the M5 site leads to a transformation from polar R3c space group (x = 0 – 0.5) to centrosymmetric Rc space group (x = 0.6–1) and to the increased integral intensity of luminescence with maxima at x = 1. It was concluded that the crystal site engineering in the Ho3+-containing β-Ca3(PO4)2-type hosts offers a promising way to obtain new NIR phosphors for use in the creation of biocompatible bone tissue fillers. |
| Remark | Link |
Fused filament fabrication for anode supported SOFC development: Towards advanced, scalable and cost-competitive energetic systems
ID=621| Authors |
|
| Source |
International Journal of Hydrogen Energy
Volume: 46,
Issue: 51,
Pages: 26174-26184 Time of Publication: 2021 |
| Remark | Link |
Thermal Conductivity and Thermoelectric Power of Compounds in the Cu–Ge–As–Se System
ID=620| Authors |
|
| Source |
Technical Physics volume
Volume: 66,
Pages: 41–45 Time of Publication: 2021 |
| Abstract | The influence of temperature (in the interval of 300–400 K) and concentrations on the electrical conductivity, thermal conductivity, and thermoelectric power of copper chalcogenide-based crystals with the general formula (GeSe)1 – x(CuAsSe2)x has been considered. Heat transfer mechanisms have been determined. It has been found that the temperature dependence of thermal conductivity is nonmonotonic with a singularity at 358 K. Thermoelectric figure of merit ZT has been calculated. |
| Remark | Link |
Modeling the process of capacitive deionization of solutions at supposing complex structure of the pores of the electrodes
ID=619| Authors |
|
| Source |
Journal of Mathematical Chemistry volume
Volume: 59,
Pages: 1054–1067 Time of Publication: 2021 |
| Abstract | An electrochemical cell was created and experimentally tested and the process of intense capacitive deionization (CDI) of aqueous solutions in a cyclic mode was studied. The paper presents a developed mathematical model for CDI process on electrodes with complex structure of pore space. This allows to describe the process and obtain results that are in good agreement with the experimental ones. Model parameters are easily determined at one stage of the deionization process. |
| Remark | Link |
Mixed ionic-electronic transport in the high-entropy (Co,Cu,Mg,Ni,Zn)1-xLixO oxides
ID=618| Authors |
|
| Source |
Acta Materialia
Volume: 208,
Pages: 116735 Time of Publication: 2021 |
| Abstract | A series of the high-entropy (Co,Cu,Mg,Ni,Zn)1-xLixO oxides with a lithium substitution level of x = 0, 0.05, 0.10, 0.15, 0.20, 0.25, and 0.30 is evaluated in terms of the crystal structure, morphology and transport properties, with thorough studies aimed at elucidation of the nature of different contributions to the total electrical conductivity. It is found that cubic Fm-3m structure is preserved in the whole investigated series, with (Co,Cu,Mg,Ni,Zn)0.8Li0.2O composition showing a high internal strain, supporting to some degree one of the so-called core effects, anticipated for the high-entropy materials. For samples with Li content x > 0.20 the strain is relaxed by formation of the oxygen vacancies. As unambiguously evidenced by DC polarization experiments and measured impedance spectroscopy data with ionically-blocking Au and reversible Li electrodes used, the previously reported in the literature transition to the lithium superionic conductivity in the Li-rich compounds, up to σi ≈ 1–10⋅10−3 Scm−1, is more complex, with emergence of the electronic conduction as well, reaching similar magnitude for (Co,Cu,Mg,Ni,Zn)0.7Li0.3O. The observed behavior upon increase of lithium concentration (x) can be explained by a qualitative change of the nature of the electronic and ionic defects present in (Co,Cu,Mg,Ni,Zn)1-xLixO series, with initial oxidation of 3d metals (mainly Co), followed by possible formation of the interstitial lithium, and final emergence of the oxygen vacancies. Furthermore, the recorded electrochemical properties of (Co,Cu,Mg,Ni,Zn)0.7Li0.3O lithium cell electrode, suggesting presence of intercalation-like behavior at the initial stages of lithiation, confirm the proposed mixed ionic-electronic conductivity. |
| Keywords | High-entropy oxides; Crystalline oxides; Lattice defects; Mixed conductor; Li-ion battery |
| Remark |
https://doi.org/10.1016/j.actamat.2021.116735 Link |
The performance of intermediate temperature solid oxide fuel cells with sputter deposited La1-xSrxCoO3 interlayer
ID=617| Authors |
|
| Source |
Journal of Electroceramics
Volume: 45,
Pages: 156–163 Time of Publication: 2020 |
| Abstract | The paper studies the performance of the intermediate temperature solid oxide fuel cells with the sputter deposited La1-xSrxCoO3 (LSC) interlayer between the cathode and electrolyte. The sputter deposition of the LSC thin films is carried out in argon gas and in a mixture of argon and oxygen gases and then are annealed at 600, 800 and 1000 °C in air for 2 h. The structure and composition of the sputter deposited LSC films are investigated by the X-ray diffraction analysis, scanning and transmission electron microscopies, and energy-dispersive X-ray spectroscopy. The polarization resistance of the sputter deposited LSC films (600 nm thick) on the symmetric cells is 0.13, 0.45 and 2.48 Ohm·cm2 measured at 800, 700 and 600 °C, respectively. Measurements are performed by electrochemical impedance spectroscopy. The maximum power density of the anode-supported solid oxide fuel cells with the yttria-stabilized zirconia/gadolinia-doped ceria bilayer electrolyte, LSC interlayer, and LSC cathode is 2.27, 1.58 and 0.68 W/cm2 measured at 800, 700 and 600 °C, respectively. These values of the power density are respectively 1.4, 1.6 and 2.3 times higher than that of the reference cell without the LSC interlayer. |
| Remark | Link |
Near-Broken-Gap Alignment between FeWO4 and Fe2WO6 for Ohmic Direct p–n Junction Thermoelectrics
ID=616| Authors |
|
| Source |
ACS Appl. Mater. Interfaces
Volume: 13,
Issue: 6,
Pages: 7416–7422 Time of Publication: 2021 |
| Abstract | We report a near-broken-gap alignment between p-type FeWO4 and n-type Fe2WO6, a model pair for the realization of Ohmic direct junction thermoelectrics. Both undoped materials have a large Seebeck coefficient and high electrical conductivity at elevated temperatures, due to inherent electronic defects. A band-alignment diagram is proposed based on X-ray photoelectron and ultraviolet–visible light reflectance spectroscopy. Experimentally acquired nonrectifying I–V characteristics and the constructed band-alignment diagram support the proposed formation of a near-broken-gap junction. We have additionally performed computational modeling based on density functional theory (DFT) on bulk models of the individual compounds to rationalize the experimental band-alignment diagram and to provide deeper insight into the relevant band characteristics. The DFT calculations confirm an Fe-3d character of the involved band edges, which we suggest is a decisive feature for the unusual band overlap. |
| Keywords | thermoelectric oxides, broken-gap junction, Ohmic contact, band alignment, p-n junction, computational first-principles modeling |
| Remark |
https://doi.org/10.1021/acsami.0c19341 Link |
Effect of the Ba/K ratio on structural, dielectric and energy storage properties of BaO–K2O–TiO2–P2O5 glass-ceramics
ID=615| Authors |
|
| Source |
Physics and Chemistry of Glasses - European Journal of Glass Science and Technology Part B
Volume: 61,
Issue: 6,
Pages: 213-221 Time of Publication: 2020 |
| Abstract | xBaO–(20–x)K2O–30TiO2–50P2O5 with (0≤x≤20 mol%) glasses were successfully elaborated by the melt quenching while their related glass-ceramics were developed by controlled crystallisation. Density and molar volume measurements, differential thermal analysis and Raman spectroscopy were carried out to examine the glassy structure, the results revealed that the addition of BaO increases the reticulation and reinforces the glass network by the creation of strengthened linkages. X-ray diffraction has identified the formation of MTi2(PO4)3 with M=(K, Ba0.5) in all the glass-ceramics (GC) and the precipitation of a secondary BaTiP2O8 phase when x increase beyond 10 mol%. The dielectric properties of the glass-ceramics were studied by impedance spectroscopy, it showed that the addition of BaO induces an enhancement of both thermal and frequency stability of the dielectric parameters (εr and tan δ). The glass-ceramic with 5 mol% of BaO GC-(x=5) presents the highest dielectric constant and the lowest dielectric loss. The P-E hysteresis loops were recorded at room temperature and the energy storage parameters of the glass-ceramics were determined. These parameters were significantly improved by the increase of the BaO content and the optimum parameters were obtained for GC-(x=5). The dielectric and energy storage parameters were discussed according to the structure data. |
| Remark |
DOI: https://doi.org/10.13036/17533562.61.6.015 Link |
