Zeitschriftenartikel: „Oxyde de lanthane strontium manganèse (LSMO)“

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McNally, Frank, Jin Hyeok Kim und F. F. Lange. „Fatigue Properties of Lanthanum Strontium Manganate–lead Zirconate Titanate Epitaxial Thin Film Heterostructures Produced by a Chemical Solution Deposition Method“. Journal of Materials Research 15, Nr. 7 (Juli 2000): 1546–50. http://dx.doi.org/10.1557/jmr.2000.0221.

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A liquid-precursor process was used to produce an epitaxial all-oxide ferroelectric memory device structure. The lanthanum strontium manganate–lead zirconate titanate–lanthanum strontium manganate (LSMO–PZT–LSMO) structure used for this device shows excellent polarization and fatigue behavior with a remnant polarization Pr of 42 µC/cm2 and a coercive field Ec of 68 keV. The polarization was found to only slightly degrade after over 1010 fatigue cycles. This behavior is contrasted with epitaxial PZT using a metal top electrode. In addition, the use of a top LSMO electrode was a sufficient barrier to Pb loss during heating to allow subsequent (or prolonged) heat treatments that would generally lead to Pb loss.

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Kulkarni, Vaishnavi M., Dhananjay Bodas und Kishore M. Paknikar. „Lanthanum strontium manganese oxide (LSMO) nanoparticles: a versatile platform for anticancer therapy“. RSC Advances 5, Nr. 74 (2015): 60254–63. http://dx.doi.org/10.1039/c5ra02731d.

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BEHERA, Swayam Aryam, Ali AMANAT und P. Ganga Raju ACHARY. „Photocatalytic degradation of ciprofloxacin drug utilizing novel PVDF/polyaniline/ lanthanum strontium manganate@Ag composites“. Journal of Metals, Materials and Minerals 34, Nr. 1 (19.12.2023): 1896. http://dx.doi.org/10.55713/jmmm.v34i1.1896.

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Poly (vinylidene fluoride) (PVDF) is the first-choice ferroelectric support or membrane material. The lanthanum strontium manganite (LSMO) is a well-known electrode material in the class of the solid oxide fuel cell (SOFC) materials. A set of four polymer composites PVDF-LSMO-PANI(5.0 wt%) with different amount of silver doping were fabricated with the silver nitrate and reducing agent. The characterization of these four novel PVDF based composites were characterized by the XRD, FTIR, SEM, UV-Visible DRS. The present communication highlights: (I) the effect of PANI in the PVDF-LSMO-PANI (PLP) composites towards the photocatalytic degradation of ciprofloxacin drug. (II) the effect of Ag doping in the Ag-PVDF-LSMO-PANI (Ag-PLP) composites towards the photocatalytic degradation of ciprofloxacin drug. It is observed that the incorporation of PANI in PVDF-LSMO and Ag in PVDF-LSMO-PANI polymer ceramic composites showed enhanced photocatalytic degradation of ciprofloxacin in the irradiation of visible radiation. The plausible separation of photo-generated e- hole pairs (e- and h+) carried on by charge migration kind of mechanism is being studied here to understand the improved photocatalytic activity of Ag-PVDF-LSMO-PANI composites.

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Zurauskiene, Nerija, Voitech Stankevic, Skirmantas Kersulis, Milita Vagner, Valentina Plausinaitiene, Jorunas Dobilas, Remigijus Vasiliauskas et al. „Enhancement of Room-Temperature Low-Field Magnetoresistance in Nanostructured Lanthanum Manganite Films for Magnetic Sensor Applications“. Sensors 22, Nr. 11 (25.05.2022): 4004. http://dx.doi.org/10.3390/s22114004.

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The results of colossal magnetoresistance (CMR) properties of La1-xSrxMnyO3 (LSMO) films grown by the pulsed injection MOCVD technique onto an Al2O3 substrate are presented. The grown films with different Sr (0.05 ≤ x ≤ 0.3) and Mn excess (y > 1) concentrations were nanostructured with vertically aligned column-shaped crystallites spread perpendicular to the film plane. It was found that microstructure, resistivity, and magnetoresistive properties of the films strongly depend on the strontium and manganese concentration. All films (including low Sr content) exhibit a metal–insulator transition typical for manganites at a certain temperature, Tm. The Tm vs. Sr content dependence for films with a constant Mn amount has maxima that shift to lower Sr values with the increase in Mn excess in the films. Moreover, the higher the Mn excess concentration in the films, the higher the Tm value obtained. The highest Tm values (270 K) were observed for nanostructured LSMO films with x = 0.17–0.18 and y = 1.15, while the highest low-field magnetoresistance (0.8% at 50 mT) at room temperature (290 K) was achieved for x = 0.3 and y = 1.15. The obtained low-field MR values were relatively high in comparison to those published in the literature results for lanthanum manganite films prepared without additional insulating oxide phases. It can be caused by high Curie temperature (383 K), high saturation magnetization at room temperature (870 emu/cm3), and relatively thin grain boundaries. The obtained results allow to fabricate CMR sensors for low magnetic field measurement at room temperature.

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Kulkarni, Vaishnavi M., Dhananjay Bodas und Kishore M. Paknikar. „ChemInform Abstract: Lanthanum Strontium Manganese Oxide (LSMO) Nanoparticles: A Versatile Platform for Anticancer Therapy“. ChemInform 46, Nr. 36 (20.08.2015): no. http://dx.doi.org/10.1002/chin.201536302.

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CESÁRIO, Moisés Rômolos, Daniel Araújo MACEDO, Bráulio Silva BARROS, Patrícia Mendonça PIMENTEL, Marcus Antonio de Feitas MELO und Dulce Maria de Araújo MELO. „SYNTHESIS AND CHARACTERIZATION OF LSM/SDC FILMS AS COMPOSITE CATHODES FOR SOLID OXIDE FUEL CELLS“. Periódico Tchê Química 07, Nr. 14 (20.08.2010): 16–22. http://dx.doi.org/10.52571/ptq.v7.n14.2010.17_periodico14r_pgs_16_22.pdf.

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The study of the strontium-doped lanthanum manganites in the form of films covers a large area of technological applications, such as ceramics semiconductors and solid oxide fuel cell cathode. Strontium-doped lanthanum manganite and samarium-doped ceria has been used as composite cathode of solid oxide fuel cells (SOFCs) because of its excellent performance in electronic and ionic conductivity. In this work, we produced films of the cathode LSM / SDC on yttria stabilized zirconia (YSZ) electrolytes. La0.8Sr0.2MnO3 (LSM) and Ce0.8Sm0.2O1.9 (SDC) powders were synthesized by a synthesis route similar to the Pechini method, in which the gelatin replaced the ethylene glycol as polymerizing agent. Precursor powders of LSM and SDC phases were calcined at 900 ºC. In the step of films production were prepared suspensions of the LSM and SDC powders with addition of ethyl cellulose as a pore-forming agent. The ceramic suspensions were deposited on YSZ electrolyte using the spin coating method. After sintering to 1150 °C for 4 h the films were characterized by XRD and SEM. The film with 10 wt.% ethyl cellulose presented porous and strongly adhered to the YSZ substrate.

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Gao, Min, Cheng Xin Li, Ming De Wang, Hua Lei Wang und Chang Jiu Li. „Influence of the Surface Roughness of Plasma-Sprayed YSZ on LSM Cathode Polarization in Solid Oxide Fuel Cells“. Key Engineering Materials 373-374 (März 2008): 641–44. http://dx.doi.org/10.4028/www.scientific.net/kem.373-374.641.

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Under SOFCs operating condition, the cathode reaction rate is determined by triple phase boundary (TPB) areas which are associated with the geometry of the interface between the cathode and the electrolyte. In this paper, YSZ electrolyte was deposited by atmospheric plasma spraying (APS). A nano-scaled lanthanum strontium manganate (LSM) cathode was prepared by sol-gel process on APS YSZ with different surface roughness to aim at increasing the TPB. The polarization curves of LSM cathode were characterized by potentiostat. The influence of the roughness of APS YSZ on the polarization of LSM cathode was investigated. It was found that the overpotential of the LSM cathode is significantly reduced with the increase of YSZ surface roughness.

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Tarragó, Diego Pereira, Célia de Fraga Malfatti und Vânia Caldas de Sousa. „Combustion Synthesis of LSM Powders from a Precursor Solution with Mixed Fuels“. Materials Science Forum 727-728 (August 2012): 1329–33. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.1329.

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For the combustion synthesis of strontium doped lanthanum manganite (LSM), different fuels can be used influencing the phase formation and also the powder morphology. Both are important features that can improve the material performance when used in a solid oxide fuel cell cathode. Urea and sucrose are fuels used to synthesize distinct LSM powders, thus the purpose of this work was to mix these fuels in order to obtain nanocrystalline LSM powders with a differentiated morphology, more convenient for the desired application. After calcination at 750°C for 3 hours the powder generated a pure phase LSM X-ray diffraction pattern and the micrographs taken in the transmission and scanning electron microscopes revealed a very peculiar morphology with specific surface area (BET) of 13 m²/g. Calcination led to a single phase and more crystalline material but showed no influence in the powder morphology.

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Rabo, Jennet R., und Rinlee Butch M. Cervera. „Fabrication of Solid Oxide Electrolysis Single Cell Using NiO-YSZ/YSZ/LSM-YSZ via Drop-Coating Method“. Key Engineering Materials 847 (Juni 2020): 129–34. http://dx.doi.org/10.4028/www.scientific.net/kem.847.129.

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Solid oxide electrolysis cell (SOEC) is a highly efficient and environmentally friendly technology for future hydrogen generation. In this study, electrolyte-supported SOEC single cell was fabricated via a simple and facile drop-coating technique. Thin film electrodes of nickel oxide/yttria stabilized zirconia (NiO-YSZ) cathode and strontium-doped lanthanum manganite/ytrria-stabilized zirconia (LSM-YSZ) anode were deposited onto yttria-stabilized zirconia (YSZ) solid electrolyte substrate. Scanning electron microscopy (SEM) with energy dispersive analysis (EDS) was used to study the microstructural properties of the heat-treated samples and revealed a successful thin film deposition of porous electrodes onto the dense YSZ substrate. XRD patterns showed the desired crystal structure of the deposited electrode thin films. Distinct phases of cubic YSZ and monoclinic LSM were observed for the LSM-YSZ anode while cubic NiO and YSZ phases were observed for the deposited cathode. Electrochemical conductivity of the cell was investigated using electrochemical impedance spectroscopy analysis (EIS) which revealed a total conductivity of about 2.0 mS/cm at 700 °C.

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Gómez, Laura, J. Escobar, Maria Teresa Colomer und Rodrigo Moreno. „Manufacture of YSZ-LSM Semi-Cell by Colloidal Processing“. Materials Science Forum 727-728 (August 2012): 746–51. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.746.

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Yttria stabilized zirconia (YSZ) is the most common electrolyte in solid oxide fuel cells (SOFC). The planar configuration is widely used for designing single cells, in which a thick cathode layer can be used as the supporting electrolyte film. The manufacture of the semi-cell formed by anode and electrolyte has been widely studied and there are many works dealing with its colloidal processing. However, the semi-cell formed by cathode and electrolyte has received much lower attention. This work deals with the manufacture of a semi-cell consisting of YSZ as electrolyte and strontium-doped lanthanum manganite (LSM) as a cathode through a colloidal processing route. The colloidal behavior of diluted suspensions of YSZ and the rheology of their concentrated suspensions were studied as a function of deflocculant content, mixing time by using ultrasounds probe and ageing time. The colloidal stability of aqueous suspensions of LSM was studied by measuring the zeta potential as a function of pH and deflocculant content. These concentrated suspensions were used to obtain thick self-sustained substrates by casting methods. The YSZ electrolyte and LSM cathode were prepared by tape casting in water medium.

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Chang, Chun Liang, Chang Sing Hwang, Chun Huang Tsai, Sheng Fu Yang, Wei Ja Shong, Te Jung Daron Huang und Zong Yang Jhuang-Shie. „Preparation and Characterization of Protective LSM Coatings Produced by Atmospheric Plasma Spraying“. Key Engineering Materials 656-657 (Juli 2015): 68–73. http://dx.doi.org/10.4028/www.scientific.net/kem.656-657.68.

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Lanthanum strontium manganite oxides with perovskite structure are widely employed materials for protective coatings on chromium-contained metallic interconnectors in the intermediated temperature solid oxide fuel cells (ITSOFCs). The application of protective coatings is used to decrease the growth of chromium oxide and the evaporation of chromium trioxide and chromium hydroxide from the surfaces of metallic interconnectors. In this study, La0.8Sr0.2MnO3-δ(LSM) protective coatings are produced by the promising atmospheric plasma spraying (APS) technique on the substrates of Crofer 22 H, Crofer 22 APU and SS441 ferritic steels with or without pre-oxidation treatment. The substrates with pre-oxidation treatment were heated to 800°C and dwelled for 12 hrs in air before APS coating process. The cross-sectional micrographs show that the LSM coatings produced by APS technique are quiet dense without penetrating cracks. The XRD results identify that the LSM coatings produced by APS under 50 kW torch power reveal desired perovskite structure without any X-ray detectable second phase. After 600 hrs ageing in air at 800°C, the initial and final ASR values of the coated Crofer 22 APU sample with pre-oxidation treatment are 1.350 and 1.694 mΩcm2, respectively. The measured ASR increasing rate is only about 0.573 μΩcm2/hr. Thus, LSM coating prepared by APS technique can dramatically decrease the growth of chromium oxide to protect the metallic interconnector and the generation of gaseous Cr-contained species to avoid cathode poisoning at the operating temperatures of ITSOFCs.

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Miloš, Vojtěch, Petr Vágner, Daniel Budáč, Michal Carda, Martin Paidar, Jürgen Fuhrmann und Karel Bouzek. „Generalized Poisson-Nernst-Planck-Based Physical Model of the O₂∣LSM∣YSZ Electrode“. Journal of The Electrochemical Society 169, Nr. 4 (01.04.2022): 044505. http://dx.doi.org/10.1149/1945-7111/ac4a51.

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The paper presents a generalized Poisson-Nernst-Planck model of an yttria-stabilized zirconia electrolyte developed from first principles of nonequilibrium thermodynamics which allows for spatial resolution of the space charge layer. It takes into account limitations in oxide ion concentrations due to the limited availability of oxygen vacancies. The electrolyte model is coupled with a reaction kinetic model describing the triple phase boundary with electron conducting lanthanum strontium manganite and gaseous phase oxygen. By comparing the outcome of numerical simulations based on different formulations of the kinetic Eqs. with the results of EIS and CV measurements we attempt to discern the existence of separate surface lattice sites for oxygen adatoms and surface oxides from the assumption of shared ones. Moreover, we show that the mass-action kinetics model is sensitive to oxygen partial pressure unlike exponential kinetics models. The resulting model is fitted to a dataset of EIS and CVs spanning multiple temperatures and pressures, using various relative weights of EIS and CV data in the fitness function. The model successfully describes the physics of the interface around the OCV.

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Tian, Jiashen, Yan Dou, Qiong Nian und Ryan J. Milcarek. „Solid Oxide Fuel Cells with 3D Inkjet Printing Modified LSM-YSZ Interface“. ECS Meeting Abstracts MA2022-02, Nr. 47 (09.10.2022): 1774. http://dx.doi.org/10.1149/ma2022-02471774mtgabs.

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Solid oxide fuel cells (SOFCs) have drawn attention as an alternative power generation technology due to demonstrated high efficiency and low emissions. The lanthanum strontium manganite (LSM)-yttria-stabilized zirconia (YSZ) cathode is utilized widely for SOFCs due to its high performance and stability. The electrochemical oxygen reduction reaction that occurs in the cathode can be enhanced by the porous LSM-YSZ cathode with good electronic and ionic conductivity. With sufficient electrochemically active reaction sites, the oxygen ion transfer processes in the mixed ionic conductor (YSZ) and at the interface of cathode and electrolyte (LSM-YSZ) become critical for the activity of the cathode. Thus, the pillar shape YSZ microstructure with ~ 150 μm×150 μm×10 μm (L×W×H) size can be fabricated by 3D inkjet printing on the interface of electrolyte and cathode to increase the TPB area and enhance the connection between the dense YSZ electrolyte and mixed YSZ ionic conductor. Scanning Electron Microscopy (SEM) is utilized to assess the morphology and microstructure of the YSZ interface. To investigate the influence of the modified interface on the performance of the SOFC, electrochemical performance testing and characterization are conducted for the SOFCs with/without the modified YSZ layer. The microstructures with different pillar central spacing are also fabricated by 3D inkjet printer to optimize the geometry of the LSM-YSZ interface.

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Avila, Romar Angelo M., Trina G. Tambago und Rinlee Butch M. Cervera. „Preparation of Porous LSM/YSZ Composite with Varying Grain Size of YSZ Precursor Using Solid State Reaction Method“. Materials Science Forum 917 (März 2018): 93–97. http://dx.doi.org/10.4028/www.scientific.net/msf.917.93.

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Lanthanum strontium manganite (LSM) and yttria-stabilized zirconia (YSZ) composite is a promising material as an anode for solid oxide electrolysis cell (SOEC) applications. In this study, LSM/YSZ with a 1:1 LSM to YSZ weight ratio was synthesized via solid state reaction method using oxide precursors of commercial micrograined size LSM with varying YSZ precursor grain size. For the YSZ precursor, both nanograined (nanoYSZ) and micrograined YSZ (microYSZ) precursors were studied. Graphite was added at 10% weight ratio as a pore former. Density measurements using Archimedes principle revealed that LSM/nanoYSZ had the highest relative density of 97.8%, whereas LSM/nanoYSZ with graphite had the lowest density of 89.1%. The addition of graphite to LSM/nanoYSZ reduced the density by 8.7% compared to the decrease of 5.5% for LSM/microYSZ. Scanning electron microscopy confirms that the addition of graphite has a greater effect on the microstructure of LSM/nanoYSZ as compared to LSM/microYSZ. The electrochemical impedance spectroscopy results show that the samples with nanoYSZ had a higher total conductivity than the samples with microYSZ. LSM/nanoYSZ and LSM/nanoYSZ with graphite revealed a total conductivity values of 0.0470 Scm-1and 0.0440 Scm-1at 700 °C with activation energies of 0.0178 eV and 0.0234 eV, respectively.

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Zhang, Yubo, und Jason D. Nicholas. „Barium Oxide (BaO) Infiltrated Lanthanum Strontium Manganese Oxide (LSM)-Gadolinium Doped Ceria (GDC) Solid Oxide Electrochemical Reduction Cells (SOERC) for Reduced Diesel NOx Emissions“. ECS Transactions 78, Nr. 1 (30.05.2017): 2381–89. http://dx.doi.org/10.1149/07801.2381ecst.

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Myung, Doo-Hwan, Jong-Ill Hong, Jae-Yeon Hwang, Jong-Ho Lee, Hae-Weon Lee, Byung-Kook Kim, Sung-Gurl Cho und Ji-Won Son. „Performance of Solid Oxide Fuel Cell with Gradient-structured Thin-film Cathode Composed of Pulsed-laser-deposited Lanthanum Strontium Manganite-Yttria-stabilized Zirconia Composite“. Journal of the Korean Ceramic Society 48, Nr. 6 (30.11.2011): 487–92. http://dx.doi.org/10.4191/kcers.2011.48.6.487.

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Canfield, Nathan, John Hardy, Christopher Coyle und Jeffry Stevenson. „EBSD Analysis of Undesired Phase Development in Solid Oxide Fuel Cell (SOFC) Lanthanum Strontium Manganese Oxide (LSM) / 8 mol% Yttrium Zirconium Oxide (8YSZ) Cathodes During Long-Term Thermal Anneal“. Microscopy and Microanalysis 25, S2 (August 2019): 2132–33. http://dx.doi.org/10.1017/s1431927619011395.

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Vibhu, Vaibhav, Izaak Vinke, Rudiger-A. Eichel und L. G. J. (Bert) de Haart. „Performance and Electrochemical Behavior of LSM Based Fuel Electrode Materials Under High Temperature Electrolysis Conditions“. ECS Meeting Abstracts MA2023-01, Nr. 54 (28.08.2023): 213. http://dx.doi.org/10.1149/ma2023-0154213mtgabs.

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High-temperature solid oxide electrolysis cells (SOECs) have gained considerable attention due to more favourable thermodynamic and electrochemical kinetic conditions over low-temperature electrolysis. The SOECs can be used for the production of hydrogen from steam electrolysis, syngas (H2 + CO) from co-electrolysis, and carbon mono-oxide from pure CO2 electrolysis. Despite several advantages, the long-term durability of SOECs is still an issue. The long-term durability of SOEC depends on the stability of electrodes as well as on the operational conditions, for example current load, temperature, and fuel gas composition. The conventional cermet-based fuel electrode i.e. Ni-YSZ shows good initial performance, however, it experiences severe degradation during long-term due to Ni- agglomeration and migration away from the electrolyte. Therefore, searching for new electrode materials is crucial in order to enhance the overall performance and durability of SOECs. In this work, we have considered Lanthanum strontium manganite-based perovskite oxides as fuel electrodes i.e. La0.6Sr0.4MnO3 (LSM). LSM is very stable chemically under oxidizing atmosphere, however, it undergoes phase transformation into a Ruddlesden-Popper (La0.6Sr0.4)2MnO4±δ phase under reducing atmosphere. We have first prepared the electrolyte-supported single cells using 8YSZ electrolyte and LSM+YSZ/LSM oxygen electrodes. The single cells were then electrochemically characterized using AC- and DC-techniques under steam electrolysis, co-electrolysis, and CO2-electrolysis conditions in 800-900 °C temperature range. Moreover, the electrochemical behaviour of LSM+GDC (50:50) and LSM+YSZ (50:50) composite electrodes containing single cells were also investigated. The LSM and LSM+GDC fuel electrode containing single cells show good electrochemical performance in all three electrolysis modes. However, lower performance is observed for LSM+YSZ fuel electrode containing single cell. For example, a current density of 997, 1025, and 511 mA.cm-2 at 1.5 V, are obtained for LSM, LSM+GDC, and LSM+YSZ fuel electrode containing single cells respectively, with 50% N2 and 50% H2O feed gas mixture at 900 °C. Furthermore, the impedance spectra were also recorded for all these cells under OCV and polarization conditions, and fitted with an equivalent circuit model using an inductor, a series resistance and 4 R//CPE elements. The impedance spectra vary significantly with the gas compositions. The detailed electrochemical results will be presented and discussed in detail.

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Budac, Daniel, Michal Carda, Martin Paidar und Karel Bouzek. „Electrical Conductivity of LSM—YSZ Oxygen Electrode for Determining Active Electrode Zone in Solid Oxide Cells“. ECS Meeting Abstracts MA2022-01, Nr. 26 (07.07.2022): 1233. http://dx.doi.org/10.1149/ma2022-01261233mtgabs.

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Solid oxide cells (SOCs) show high potential in applications related to sustainable society. The substantial contribution of the SOCs is their high efficiency in terms of the electric energy utilization due to the operating temperature up to 800 °C. The effect of high operation temperature is favorable in two ways. Firstly, it accelerates the kinetics of electrochemical reactions preventing the need of the use of Pt-based catalysts. Secondly, the high temperature offers favorable thermodynamic conditions decreasing the equilibrium potential for water splitting. This makes the SOCs technology a direct competitor to low-temperature technologies, such as alkaline or PEM electrolysis. The SOCs are composed of electrolyte, fuel electrode and oxygen electrode. The electrolyte allows transport of oxygen ions between the electrodes due to its high ionic conductivity. Yttria-stabilized zirconia (YSZ) represents a typical example of such a material. The oxygen electrode is where the oxygen reduction reaction or the oxygen evolution reaction takes place according to the operation mode of the SOC. Lanthanum strontium manganite (LSM) has been the state-of-the-art oxygen electrode material for almost 25 years and is considered as a pure electron conductor. Lack of ionic conductivity of the LSM leads to limitation of the overall reaction rate to the amount of triple phase boundary (TPB) where gaseous phase, electron-conducting phase and ion-conducting are in simultaneous contact. According to the literature it is optimal for the electrode material to be mixed in the 50:50 ratio with YSZ to increase the amount of the TPB. Thus, the active zone is extended further from the electrolyte surface into the volume of the electrode body. Even though the mixed electrode material exhibits great performance, information on the optimal thickness of the electrode is scarce in the literature. The electrode thickness is a crucial parameter since not all of the electrode volume is electrochemically active and represents just surplus resistance for the electric current impairing the overall electrode performance. The goal of our research is to determine of the extent of the active zone that we can estimate the optimal thickness of the LSM—YSZ electrode for various operation conditions. A macrohomogenous 1D model was developed to simulate the active electrode zone extent. Initial parametric study has shown that the extent of the active region of the electrode is influenced by many factors including the kinetics of the occurring reactions, the ionic and electronic conductivity of the respective domains and working conditions, such as temperature and operating current density. Even though the literature offers data on the conductivity of bulk the LSM and YSZ, the data of the respective conductivities in the LSM—YSZ are not applicable due to the electrode structure. The conductivity of the structure consisting of packed particles with a small contact area is limited by the contact resistance. This study targets to determine the electronic conductivity of the LSM phase and the ionic conductivity of the YSZ phase in the LSM—YSZ electrode framework. The LSM conductivity in the electrode framework was determined by resistance measurement of the casted layers of the LSM—YSZ using electrochemical impedance spectroscopy (EIS). The results show an exponential decrease of the LSM conductivity with decreasing LSM content. Furthermore, the 50:50 LSM—YSZ exhibits conductivity comparable to that of the bulk YSZ electrolyte. This result proves that the energy losses due to the electrical resistance of the LSM—YSZ electrode cannot be neglected in the terms of SOC performance. The determination of the ionic conductivity of YSZ in the electrode framework required the substitution of LSM with an inert material. The material of choice was CaSO4 due to its availability and its melting point being relatively close to that of the LSM. Similarly to the LSM, YSZ exhibited an exponential decrease of ionic conductivity with a decrease in YSZ volume fraction in the samples. Furthermore, the trend was compared to the Koh-Fortini relationship, showing that grain boundaries have a strong influence on the total conductivity of the material. The results of the experiments helped us to determine the extent of the active electrode zone leading to the estimation of optimal thickness of the LSM—YSZ oxygen electrode thickness. The authors acknowledge the financial support of the Czech Science Foundation (GACR), contract No: 19-142-44-J and by the Technology Agency of the Czech Republic under project no. TK04030143.

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Franceschi, Giada, René Heller, Michael Schmid, Ulrike Diebold und Michele Riva. „Evolution of the surface atomic structure of multielement oxide films: curse or blessing?“ Nanoscale Advances, 2023. http://dx.doi.org/10.1039/d3na00847a.

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Atomically resolved scanning tunneling microscopy (STM) and x-ray photoelectron spectroscopy (XPS) are used to gain atomic-scale insights into the heteroepitaxy of lanthanum-strontium manganite (LSMO, La1−xSrxMnO3-δ, x ≈ 0.2) on SrTiO3(110)....

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Kulkarni-Dwivedi, Neha, Pratikshkumar R. Patel, Bhupendra V. Shravage, Rinku D. Umrani, Kishore M. Paknikar und Sachin H. Jadhav. „Hyperthermia and doxorubicin release by Fol-LSMO nanoparticles induce apoptosis and autophagy in breast cancer cells“. Nanomedicine, 16.01.2023. http://dx.doi.org/10.2217/nnm-2022-0171.

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Background: Studies on the anticancer effects of lanthanum strontium manganese oxide (LSMO) nanoparticles (NPs)-mediated hyperthermia at cellular and molecular levels are scarce. Materials & methods: LSMO NPs conjugated with folic acid (Fol-LSMO NPs) were synthesized, followed by doxorubicin-loading (DoxFol-LSMO NPs), and their effects on breast cancer cells were investigated. Results: Hyperthermia (45°C) and combination treatments exhibited the highest (∼95%) anticancer activity with increased oxidative stress. The involvement of intrinsic mitochondria-mediated apoptotic pathway and induction of autophagy was noted. Cellular and molecular evidence confirmed the crosstalk between apoptosis and autophagy, involving Beclin1, Bcl2 and Caspase-3 genes with free reactive oxygen species presence. Conclusion: The study confirmed hyperthermia and doxorubicin release by Fol-LSMO NPs induces apoptosis and autophagy in breast cancer cells.

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Knapp, P., und J. Abiade. „Analysis of Ferromagnetic-Multiferroic Interfaces in Epitaxial Multilayers of LSMO and BFO“. Journal of Undergraduate Research at the University of Illinois at Chicago 6, Nr. 1 (01.01.2013). http://dx.doi.org/10.5210/jur.v6i1.7518.

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Bilayers were fabricated from ferromagnetic LSMO (Lanthanum Strontium Manganate Oxide, La0.7Sr0.3MnO3) and ferroelectric BFO (Bismuth Ferrite, BiFeO3) using pulsed laser deposition in the presence of O2 on LaAlO3and SrTiO3 substrates. The layer thickness and the layer order were varied among 16 samples. The bilayers were analyzed using TEM, XRD, XRR, and XPS to determine the stoichiometry, interlayer diffusion, roughness, and other structural features. TEM imaging showed that portions of the bilayers were highly crystalline. However, XRD analysis demonstrated that the majority of films were amorphous, with some polycrystalline and nanocrystalline samples. XRR data indicated a high roughness but did not yield good thickness values. Finally, XPS confirmed that material stoichiometry was preserved. It appears that the deposition process still needs optimization. This research will serve as the basis for future experiments on the magnetic properties of LSMO/BFO bilayers.

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Kaur, Yashpreet, und Bhupendra Chudasama. „Effect of Sr-Doping on Structural and Magnetic Properties of La1−xSr_xMnO₃ Nanoparticles“. Nano, 23.11.2022. http://dx.doi.org/10.1142/s1793292022500898.

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Polycrystalline La[Formula: see text]SrxMnO3 ([Formula: see text]–0.4) lanthanum strontium manganese oxide (LSMO), nanoparticles exhibit interesting size-dependent structural and magnetic properties. LSMO nanoparticles have attracted considerable attention in recent years because of their tunable magnetic properties like intrinsic and extrinsic colossal magnetoresistance, single domain superparamagnetic structure with near room temperature Curie point ([Formula: see text]). They find interesting applications in catalysis, biomedicine and data storage. Properties of LSMO nanoparticles are strongly correlated to extent of Sr-doping at La-site, their particle size and the extent to which different crystallographic phases (rhombohedral/orthorhombic) appear. A major aim of this study is to understand the effect of Sr-doping on the structural and magnetic properties of LSMO nanoparticles synthesized via the sol–gel auto combustion route. Structural and magnetic properties were investigated by powder X-ray diffraction coupled with Rietveld refinement and vibrating sample magnetometer, respectively. Rietveld refinement of diffractograms revealed that irrespective of Sr-doping, LSMO nanoparticles were crystallized in rhombohedral ([Formula: see text]) and orthorhombic (Pbnm) mixed phases. The rhombohedral phase appears to be the dominant crystallographic phase. VSM study revealed that irrespective of Sr-doping LSMO nanoparticles exhibit soft ferromagnetic behavior. With the increase in Sr-doping, saturation magnetization ([Formula: see text]) of LSMO nanoparticles increases, while their Curie temperature remains constant at [Formula: see text][Formula: see text]K. To establish the correlation between structural and magnetic properties of LSMO nanoparticles, [Formula: see text]–[Formula: see text] curves were fitted with modified Langevin function. It was observed that with an increase in Sr-doping, magnetic domain size, polydispersity and saturation magnetization increase. This increase is attributed to the corresponding increase in the rhombohedral phase fraction of LSMO nanoparticles. Thus, through Sr-doping, the magnetic properties of LSMO nanoparticles can be tuned by controlling their crystallographic phase fractions.

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Jenkins, Cody, Jiashen Tian, Yan Dou, Qiong Nian und Ryan J. Milcarek. „Solid Oxide Fuel Cells with 3D Inkjet Printing Modified LSM-YSZ Interface“. ECS Journal of Solid State Science and Technology, 23.05.2024. http://dx.doi.org/10.1149/2162-8777/ad4fbf.

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Abstract In this study, pillar shaped yttria-stabilized zirconia (YSZ) 3D microstructures with ~60 to 90 m diameter and 12 to 20 m height are fabricated by 3D inkjet printing to improve the topology of the electrolyte/cathode interface. The microstructures increase the surface area of the cell by ~ 2.4% to 4.0% and enhance the connection between the dense YSZ electrolyte and mixed YSZ-lanthanum strontium manganite (LSM) cathode. The morphology and microstructure of the YSZ interface are characterized with scanning electron microscopy. Polarization curves confirm that the power density improves by 47% to 107% at 0.55V, depending on the dimensions of the microstructures, in comparison to a flat interface. The non-linear improvement in power density with the size of microstructures is confirmed by calculating the uncertainty with repeated tests. Based on electrochemical impedance spectroscopy and distribution of relaxation times analysis, the performance improvement is attributed to changes in the oxygen surface exchange kinetics and O2- diffusivity in the cathode.

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Ewald, Daniel, Cedric Grosselindemann, Daniel Esau, Franz-Martin Fuchs und Andre Weber. „Stack-like Contacting in Solid Oxide Cells: Electrochemical Characterization and Modeling“. Journal of The Electrochemical Society, 03.04.2024. http://dx.doi.org/10.1149/1945-7111/ad3a16.

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Abstract The integrity of metallic interconnectors (MIC) in an solid oxide cell stack is crucial because contact resistances or limitations in gas supply may occur. In this contribution, a Crofer 22 APU® interconnector with a (Mn, Co, Fe)3O4 spinel oxide (MCO) coating and a lanthanum-strontium-manganese-cobalt oxide (LSMC) contact layer at the air side was investigated. The electrochemical behavior was characterized by means of IV-characteristics, impedance spectroscopy and DRT analysis. In particular, the contact losses at the air side were measured with targeted potential probes. With respect to the contact layer mounted in a dried state, the application of a stack-like clamping pressure of 1 MPa showed a significant decrease of the contact resistance. In order to extend an existing zero-dimensional performance model for an electrolyte-supported cell with a Ni/GDC fuel electrode and LSCF air electrode, a method was established to parameterize contact losses at the air electrode. The observed activation energy of the contact losses showed to be independent of the clamping pressure. Additionally, the dependency of the cell´s intrinsic ohmic losses towards the steam partial pressure at the Ni/GDC fuel electrode was quantified and included to the model. Simulation studies were validated with experimental data for technical operating conditions.

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Lanzini, A., P. Leone, M. Santarelli, P. Asinari, M. Calì und R. Borchiellini. „Performances and Degradation Phenomena of Solid Oxide Anode Supported Cells With LSM and LSCF Cathodes: An Experimental Assessment“. Journal of Fuel Cell Science and Technology 6, Nr. 1 (25.11.2008). http://dx.doi.org/10.1115/1.2971128.

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The performance of solid oxide fuel cells is affected by various polarization losses, usually grouped in Ohmic, activation, and concentration polarizations. Under typical operating conditions, these polarization losses are largely dependent on cell materials, electrode microstructures, and cell geometry: as an example, the performance of a tubular cell is strongly limited by the Ohmic polarization due to the long current path of electrons, while in a planar cell each of these losses has a comparable effect. It is therefore of interest, in the case of planar geometry, to investigate the main performance limiting factors. In this paper, a performance evaluation of planar circular-shaped seal-less SOFC cells was performed. Two different designs of planar cells are considered. Both have a porous NiO-YSZ (yttria stabilized zirconia) anode as mechanical support, a NiO-YSZ anode active layer, and an YSZ electrolyte, and they only differ in the cathode design: (1) strontium doped lanthanum manganate (LSM)-YSZ cathode functional layer and LSM cathode current collector layer; (2) yttria doped ceria blocking layer and lanthanum strontium cobalt ferrite oxide (LSCF) functional layer. The characterization was performed by taking V-I measurements over a range of temperatures between 650°C and 840°C with hydrogen as fuel and air as oxidant. The experimental data analysis consisted in the analysis of some typical performance indicators (maximum power density (MPD); current density at 0.7V). The dependence of the cell performance on the various polarization contributions was rationalized on the basis of an analytical model—through a parameter estimation of the experimental data—devoted to the determination of the main polarization losses. Based on the results of the investigation, it is concluded that LSCF cathodes are really effective in decreasing the cathode activation polarization, allowing the reduction in operating temperature.

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Antunes, Rui, Tomasz Golec, Mirosław Miller, Ryszard Kluczowski, Mariusz Krauz und Kazimierz Krząstek. „Geometrical Optimization of Double Layer LSM/LSM-YSZ Cathodes by Electrochemical Impedance Spectroscopy“. Journal of Fuel Cell Science and Technology 7, Nr. 1 (05.11.2009). http://dx.doi.org/10.1115/1.3117606.

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The present-day high-temperature solid oxide fuel cells (SOFCs), based on yttria-stabilized zirconia (YSZ) electrolyte, a lanthanum-strontium manganite (LSM) cathode and a nickel-YSZ cermet anode, operate at 800–1000°C. Cathode materials are restricted to doped lanthanum manganites due to their stability in oxidizing atmosphere, sufficient electrical conductivity, and thermal expansion match to the YSZ electrolyte. Reduction in the operating temperature of SOFCs is desirable to lower the costs and to overcome the technological disadvantages associated with elevated temperatures. However, as the operating temperature is reduced, the decrease in the LSM conductivity and increase in interfacial polarization resistances between the LSM cathode and YSZ electrolyte become critical. Therefore, different approaches have been proposed to improve interfacial quality and electrochemical performance of the LSM/YSZ cathode. The length of the triple-phase boundary (TPB) correlates well with the interfacial resistances to electrochemical oxidation of hydrogen at the anode and reduction in oxygen at the cathode. The extension of the TPB or the number of active reaction sites becomes, therefore, a determining factor in improving electrode performance. This can be achieved by developing electrode materials of higher ambipolar conductivity and by optimizing the microstructure of the electrodes. In order to improve SOFC performance, both composition and structure of the LSM/YSZ interface and of the cathode should be optimized. Recently, functional grade materials (FGMs) were introduced for SOFC technology. However, all studies reported in the literature so far, were focused on cathodes with only compositional gradient. On the other hand, intuitionally the best structure for a functional SOFC should be characterized by both compositional and porosity gradients. Fine grains (and high surface area) close to the electrode/electrolyte surface and large grains (and thus large pore size) at the air/oxygen side are expected to be of advantage. In the present study, “symmetrical” cathode-electrolyte-cathode SOFC single cells were fabricated. The cells consisted of the functional grade LSM cathode with YSZ/LSM cathode functional layer and LSM contact layer. The effects of various geometrical and microstructural parameters of cathode/functional layers on the overall cell performance were systematically investigated. The parameters investigated were the (1) cathode functional layer thickness and grain size and (2) the LSM contact layer thickness. Cathode performances were tested by means of electrochemical impedance spectroscopy (EIS) over a temperature range of 650–950°C, using air as oxidant. The dependence of cell performance on various parameters was rationalized by a comprehensive microscale model. A cathode polarization corresponding to 0.14–0.4 Ω cm2 at 750°C was achieved in this manner.

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„Barium Oxide (BaO) Infiltrated Lanthanum Strontium Manganese Oxide (LSM)-Gadolinium Doped Ceria (GDC) Solid Oxide Electrochemical Reduction Cells (SOERC) for Reduced Diesel NOx Emissions“. ECS Meeting Abstracts, 2017. http://dx.doi.org/10.1149/ma2017-03/1/194.

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