bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Strategy: Achieving High-Performed SOCs Using Sonic-Spraying as an Advanced Manufacturing
Authors: Lee Sang Won , Kim Suji , Jeong Baek Yun , Lee Seok Hee , Shin Tae Ho 
Published: September 2023

Many studies have been reported for not only efficient production of hydrogen via SOECs but also high performed SOFCs, and La1-xSrxGa1-yMgyO3-δ (LSGM), a substitute for yttria-stabilized zirconia (YSZ) has emerged as a rising candidate for the electrolyte due to its superior ionic conductivity even in intermediate temperature (≤1073K). Since solid oxide electrochemical devices with LSGM can work in intermediate temperatures, it can have better durability and efficiency at lower temperature operating conditions. However, a few essential requirements must still be addresses for the widespread use of commercial LSGM based electrochemical device; their lower mechanical strengths and higher reactivity with electrode compared to the YSZ based electrolyte makes it difficult to find a cost-effective manufacturing process and compatible materials. In this regard, several strategies for advanced manufacturing have been carried for competitive commercialization of LSGM based SOCs at KICET: (a) lowering temperature processing, (b) ultra-thinner self-standing electrolyte, (c) non-touchable electrode coating processing, and (d) optimal buffer layer. Our innovative activity on the recent LSGM based SOCs will be discussed in detail.
Consequently, the fabricated cell exhibits outstanding maximum power density of 1.40 W cm-2 with the ohmic resistance of 0.131 Ω cm2 at 1073K through the effects of the thinner buffer layer and modified electrode surface via the simple-step sonic spraying technique. When the higher electrolysis performance was, subsequently, achieved on reverse SOC operation mode; a high current density of 1.01 A cm-2 at 1073 K, when applied 1.3 V.

Fig. (a) The cell performance using nano CMF decorated LSCM cathode on (a) fuel cell (H2 fuel)

Figure 1
Computational Modeling for Cr and S Poisoning Pathways on La0.6Sr0.4Co0.2Fe0.8O3 Surfaces
Authors: Liu Bill , Yildiz Bilge 
Published: September 2023

Perovskite oxygen electrode degradation caused by cation segregation sets the limit of performance and lifetime of solid oxide fuel cells (SOFC) [1][2]. For the state-of-art perovskite oxygen electrode, (La0.6Sr0.4)0.95Co0.2Fe0.8O3-δ (LSCF), the commonly known degradation mechanism is through Sr segregation, which can be further poisoned by Cr and as well as by S impurities to form insulating layers, limiting the oxygen evolution reaction (ORR) [3][4]. In order to advance our understanding of Cr and S poisoning pathways on LSCF surfaces, we will combine ab initio density functional theory (DFT) reaction energetics, defect chemistry, and microkinetic modeling to establish a quantitative model to find the deposition reaction on different termination slabs. To predict the reaction mechanism and kinetics of Cr and S poisoning reactions, we will study CrO3 and SO2 molecules deposition pathways on pristine LSCF, and surface-modified (eg. Hf, Zr, Pr, Nd, Ce surface-doped) LSCF slabs. I will correlate adsorption energies with LSCF surface characteristics to explain the origin of the deposition, and use these characteristics to evaluate the effectiveness of the surface infiltration. Ab initio molecular dynamics (AIMD) will be applied at different ensembles to investigate further steps of the reaction, and show how the surface modification will inhibit poisoning reactions. These findings will help to guide the design of better performance and more durable oxygen electrodes for SOFCs.
[1] Neagu, D., Tsekouras, G., Miller, D. N., Ménard, H., &amp; Irvine, J. T. (2013). In situ growth of nanoparticles through control of non-stoichiometry. Nature Chemistry, 5(11), 916–923.
[2] Lee, K. T., &amp; Wachsman, E. D. (2014). Role of nanostructures on SOFC performance at reduced temperatures. MRS Bulletin, 39(9), 783–791.
[3] Jiang, S. P., &amp; Chen, X. (2014). Chromium deposition and poisoning of cathodes of solid oxide fuel cells – a review. International Journal of Hydrogen Energy, 39(1), 505–531.
[4] Chen, K., &amp; Jiang, S. P. (2020). Surface segregation in solid oxide cell oxygen electrodes: Phenomena, mitigation strategies and electrochemical properties. Electrochemical Energy Reviews, 3(4), 730–765.
The Investigation of Current Collector Layers and Design Modification of SOFCRoll Cell with LCNT-Based Electrode
Authors: Nowicki Kamil Maciej , Irvine John Thomas Sirr 
Published: September 2023

The Solid Oxide Fuel Cells (SOFCs) with an alternative fuel electrode based on the nickel-doped lanthanum calcium titanate (La0.43Ca0.37Ni0.06Ti0.94O3-γ, LCNT) were produced with alternative SOFCRoll geometry. The SOFCRoll is a self-supporting cell based on a double spiral shape, where all the layers are tape cast, rolled and fired in a single step. The SOFCRoll has the advantage of the planar system, thick film manufacturing techniques, robustness of the tubular design and very high volumetric surface area. In the previous work, 27.75 cm2 of surface area was incorporated in a spiral structure with a volume of about 2.5 cm3.
For cell production, all tapes were cast on each other by sequential casting and co-sintered at 1350 °C. The cell assembly included one layer of La0.43Ca0.37Ni0.06Ti0.94O3-γ /Zr0.92Y0.08O2-γ composite fuel electrode with 50% of LCNT by volume (LCNT/YSZ50), two layers of Zr0.92Y0.08O2-γ (YSZ) electrolyte, one layer of (La0.8Sr0.2)0.95MnO3 /Zr0.92Y0.08O2-γ active oxygen electrode with 50% of LSM (LSM/YSZ50), and LSM/YSZ current collector layer with high 90% of LSM content (LSM/YSZ10). The described methodology allowed to co-sinter four different layers of ceramic material and produced a stable SOFCRoll cell with minimum internal defects. The shrinking profile during sintering was the most crucial factor and was controlled by the initial pre-sintering of the material and the size of the particles.
The current paper presents further work on cell optimisation to improve the current collection and gas distribution within a cell structure. The design modification and co-sintering of the current collector fuel electrode layer with high Ni content allowed for the optimal use of 12 cm2 surface area in the smaller cell version. The use of shorter tapes gave shorter diffusion and current collection distance; also, the LSM/YSZ10 layer was not needed, as the whole area of the oxygen electrode was exposed for current collection purposes. While for the fuel electrode side, new tapes for the current collector were developed, such as LCNT/Ni50 composite with 50% of Ni by volume and Ni/YSZ10 composite with 90% of Ni by volume. Moreover, the co-casting method for SOFCRoll preparation was modified and improved. Giving better control over co-cast tape parameters and letting to avoid structural defects created during a cell assembly.
The paper aims to deliver the complete procedures behind the manufacturing and testing of SOFCRoll with a new configuration and assembly. These include the guidelines for material preparation and processing, tapes development, analysis of shrinking profile, cell assembly, set up of electrochemical test, data interpretation and post-mortem analysis.
An Analysis of Capacitive Contributions of the Cell Impedance during High-Temperature CO2 and Co-Electrolysis
Authors: Dittrich Lucy , Vinke Izaak C. , Eichel Rudiger-A , de Haart L.G.J. (Bert) 
Published: September 2023

High-temperature electrolysis is often studied by electrochemical impedance spectroscopy (EIS). The EIS spectra are analyzed using equivalent circuit models (ECM). In many cases, these models use basic elements such as resistor, capacitances or inductances. The discussion of the modelling results is often limited to resistances [e.g. 1-4]. Only some rare papers discuss capacitances as well [e.g. 5-7]. A detailed analysis of all capacitive contributions of the overall cell impedance in electrolysis mode in dependence on temperature, current and composition is missing in literature.
The present study provides this detailed analysis of the capacitive contributions, which in the models are usually represented by constant phase elements (CPEs). Impedance spectroscopy measurements of high-temperature CO2 and co-electrolysis on conventional fuel electrode supported cells were performed. The cells consisted of a Ni/YSZ fuel electrode, a YSZ electrolyte, a GDC barrier layer and a (La,Sr)CoO3 air electrode. The spectra were analyzed by an ECM consisting of an inductance, a serial resistance and four RQ elements (resistance and constant phase element in parallel). The dependences of the resistances on operating conditions were already reported elsewhere [1,8].
The variation of the parameters temperature, current and composition showed different trends for the single elements. For example, the capacitive contribution of processes 1 – 3 (high to middle frequency range) increases with temperature while it decreases for process 4 (low frequency range). The low frequency process had been assigned to a gas phase diffusion process according to the dependence of the corresponding resistance [1]. The CPE element of process 4 also shows a prominent dependence on the current density. This might correlate with the changing ratio of CO2 to CO in the gas phase and thus support the assignment. Further results of the dependencies of the elements will be presented and discussed.
[1] S. Foit, L. Dittrich, T. Duyster, I. Vinke, R.-A. Eichel, L.G.J. de Haart, Processes
2020, 8, 1390.
[2] S.E. Wolf, L. Dittrich, M. Nohl, T. Duyster, I.C. Vinke, R.-A. Eichel, L.G.J. de Haart, J. Electrochem.
Soc.
2022, 169, 034531.
[3] S.D. Ebbesen, X. Sun, M. B. Mogensen, Faraday Discuss.
2015, 182, 393–422.
[4] A. Leonide, V. Sonn, A. Weber, E. Ivers-Tiffée, J. Electrochem. Soc.
2008, 155, B36.
[5] S. Primdahl, M. Mogensen, J. Electrochem. Soc.
1997, 144, 3409.
[6] E.-C. Shin, J. Ma, P.-A. Ahn, H.-H. Seo, D. T. Nguyen, J. S. Lee, Electrochim. Acta
2016, 188, 240-253.
[7] X. Ge, C. Fu, S. H. Chan, Phys. Chem. Chem. Phys.
2011, 13, 15134-15142.
[8] L. Dittrich, Tailoring of the Synthesis Gas Composition during High-Temperature Co-Electrolysis (Aachen, Germany) (2021).
Performance and Electrochemical Behavior of LSM Based Fuel Electrode Materials Under High Temperature Electrolysis Conditions
Authors: Vibhu Vaibhav , Vinke Izaak , Eichel Rudiger-A , de Haart L.G.J. (Bert) 
Published: September 2023

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.
Pt Current Collectors Artificially Boosting Ceria Oxygen Surface Exchange Coefficients
Authors: Ma Yuxi , Burye Theodore E. , Nicholas Jason 
Published: September 2023

The SOFC/SOEC community has an oxygen surface exchange measurement reproducibility crisis. This is exemplified by a >1,000 times variation in the literature-reported chemical oxygen surface exchange coefficient (k
chem) values of Pr0.1Ce0.9O2−x
(PCO) at 700 °C in air, a >10,000 times variation in the literature-reported k
chem values of La0.6Sr0.4FeO3-x (LSF) at 650 °C in air, and a >100,000 times variation in the literature-reported k
chem values of Ba0.6Sr0.4Co0.8Fe0.2O3-x (BSCF) at 500 °C in air. Many of these k
chem values have been determined electrically (often via Electrochemical Impedance Spectroscopy or Electrical Conductivity Relaxation) using precious metal current collectors. Unfortunately, the Time-of-Flight Secondary Ion Mass Spectroscopy and Curvature Relaxation k
chem measurements performed here on Pulsed Laser Deposited Pr0.1Ce0.9O2−x
(PCO) thin films show that unpolarized Pt current collectors can dramatically improve PCO k
chem values (by up to 2 orders of magnitude) through i) a reduction in the PCO surface Si concentration, and/or ii) Pt diffusion into the underlying PCO lattice. Further, this phenomenon can occur in PCO thin films only exposed to mild temperatures of 500 °C. Hence, it seems likely that precious metal current collectors may be responsible for at least some of the large k
chem variation reported in the literature for “identical” materials tested under “identical” conditions.
Reference: Ma Y, Burye TE, Nicholas JD. Pt Current Collectors Artificially Boosting Praseodymium Doped Ceria Oxygen Surface Exchange Coefficients. Journal of Materials Chemistry A. 2021; 9: 24406.
Integration of Reversible Solid Oxide Electrolysis (rSOC) to Wastewater Treatment Plants for Sustainable Green Gas Production and Balancing of Green Power
Authors: Weiss Robert , Rautanen Markus , Saarinen Ville , Kiviaho Jari , Pennanen Jari , Himanen Olli 
Published: September 2023

Biogas produced from anaerobic digestion (AD) of sewage sludge and organic wastes at wastewater treatment plants (WWTPs) can present an important energy contribution to a sustainable society. This raw biogas contains typically 50-65 molar% methane (CH4) and 50-35 molar% carbon dioxide (CO2). The raw AD biogas can be further upgraded to biomethane (with over 98 molar% CH4). This is a sustainably produced gas of biological origin which has same usability and energetic properties as fossil natural gas. Either by use as biofuel in transportation, local combined heat and power (CHP) or directly fed into the gas grid, biomethane has become a vital non-fossil energy source in Europe but also other parts of the world.
During the CO2 separation step of biomethane upgrading, substantial amounts of CO2 are emitted to the atmosphere. A methanation unit can convert this CO2 into sustainable Synthetic Natural Gas (SNG), with a strong potential to be used as additional biomethane (SNG-Biomethane). The methanation unit can replace the conventional carbon dioxide (CO2) separation unit for biomethane upgrading, but needs addition of hydrogen from water electrolysis, e.g. high performance Solid Oxide Electrolysis (SOE). Such SOE can also be built as a novel high-performance reversible Solid Oxide Electrolysis (rSOC), as demonstrated in the European H2020 project BALANCE. Besides the SOE mode, such rSOC can operate also in the opposite fuel cell direction (SOFC): In times when power demands exceed sustainable supply, the SOFC mode of the rSOC can convert raw AD biogas directly to electricity. In this way, WWTPs can act as energy storage solutions to buffer temporal electrical energy surplus and produce domestic sustainable SNG to the transport sector or the gas grid. At the same time, the rSOC provides a concept of zero-emission power production. To highlight the zero-emission potential of the rSOC, this paper emphasizes author’s earlier results from the European H2020 project DEMOSOFC, which demonstrated zero-local emission SOFC using raw biogas from WWTP sewage sludge and organic wastes.
In this paper, profitability estimations for optimal rSOC and methanation investment and operation strategies at a modern city level WWTP in Finland, Europe, are presented. Power used in rSOC electrolysis mode (SOEC) origins from intermittent green power sources such as wind power, while power produced in rSOC fuel cell mode (SOFC) uses raw AD biogas. For the assessment, we utilize a dedicated Power-to-X optimization model which combines optimally power market operations, dimensions of renewable power sources, plant dimensions and operational scheduling strategies. The assessment showed high profitability using European gas crisis power market data 2021-2022, resulting in sustainable biomethane net production costs of 30-70 €/MWh.
Degradation Analysis of SOFC Performance for Long-Term Operation with High Fuel Utilization (2)
Authors: Asano Koichi , Imabayashi Takumi , Ido Akifumi , Morita Hiroshi , Yamamoto Tohru , Mugikura Yoshihiro 
Published: September 2023

Solid oxide fuel cells (SOFCs) are a power generation technology with its high efficiency and low environmental impact, and the most important issue for SOFC for practical use is to improve reliability as well as high efficiency. A national project on SOFC development in Japan, “Development of advanced evaluation and analysis technologies for the durability of Solid Oxide Fuel Cells stacks (2020-),” has been initiated as a NEDO project in order to clarify their long-term durability and find dominant degradation factor for each SOFC stacks. Central Research Institute of Electric Power Industry (CRIEPI) has operated three kinds of different SOFC cell/stacks (flat-tubular and two kinds of planer) for durability under NEDO’s project, which have been developed by KYOCERA, MORIMURA SOFC Technology, and DENSO.
Long-term durability tests of 20,000 hours have been conducted under high fuel utilization of 80% and 85%, which is close to the operating limit of each SOFC cell/stack for high efficiency, to evaluate the effects on the performance and degradation behavior of the cell/stack. In previous projects, we have developed an electrode polarization model that can accurately represent SOFC performance, including cell voltage and each overvoltage, under a variety of conditions. The degradation factors for durability of each SOFC cell/stack have been analyzed by using this model. The analysis revealed that the dominant degradation factors were increased cathode overvoltage and IR loss, similar to the SOFC cell/stacks that were modified from the previous project to improve their long-term durability. On the other hand, the degradation rate of cell voltage was higher at 85% than at 80% fuel utilization in one cell/stack, and the performance degradation factor analysis revealed that this difference was due to an increase in anode overvoltage at 85% than at 80% fuel utilization, where anode overvoltage was not the primary degradation factor.
This work has been carried out under the projects (JPNP13001 and JPNP20003) of the New Energy and Industrial Technology Development Organization (NEDO), Japan as contract research. We would like to express our gratitude to NEDO, many SOFC developers, as well as to university partners and National Institute of Advanced Industrial Science and Technology (AIST).
Rapidly Direct Laser 3D Printing of High-Performance Protonic Ceramic Fuel Cells
Authors: Tong Jianhua 
Published: September 2023

Fuel cells with a dense ionic conducting electrolyte layer sandwiched between two porous electrode layers are one of the most efficient fuel-to-electricity energy conversion devices. Their reversible operation can also efficiently electrolyze water to hydrogen, reduce carbon dioxide to fuels, synthesize ammonia, upgrade fuels, and store energy on large scales. Compared with the popular low-temperature (~80 oC) proton exchange/polymer electrolyte membrane fuel cells and the high-temperature (700-1000 oC) oxygen ion-conducting solid oxide fuel cells (SOFCs), initially used in electric vehicles, auxiliary powers, power plants, and hydrogen electrolyzers, the rising star of protonic ceramic fuel cells (PCFCs) based on proton conducting oxide electrolytes offers excellent suitability for operating at 400-700 oC, the optimum temperature range for electrochemical energy devices, enabling extensive superiorities (high efficiency and performance, long thermal and chemical stabilities, flexible fuels, and cost-effective compatible materials) compared to their counterparts. In recent ten years, many high-performance PCFCs have been reported. However, most performances were achieved using small-area button cells (<0.5cm2) fabricated using spin coating, drop coating, manual brushing, and screen printing of electrolytes on the dry-pressed anode supports, followed by co-firing. There are challenges to transferring the excellent microstructures and materials chemistries/properties obtained from small-area cells to large-area cells and stacks. Furthermore, the decrease in cell component layer thickness for high volumetric cell performance and the requirement for more efficient, faster, and more cost-effective manufacturing motivated the advanced manufacturing of PCFCs.
This work will focus on the direct laser 3D printing (DL3DP) of PCFCs performed at Clemson University. The DL3DP integrated 3D printing (microextrusion and ultrasonic spraying) and laser processing (drying, sintering, and machining), allowing for manufacturing PCFC components, single cells, and stacks with the desired microstructures and geometries irrelevant to the area. The DL3DP could rapidly and cost-effectively manufacture PCFCs without conventional long-term furnace processing. The processing speed could be 2 orders of magnitude faster than the conventional tape-casting and furnace co-firing method. The achieved cells and stacks showed excellent fuel cell performance and less dependence on the effective area. The cells showed peak power densities 1.6-2.6 times that of the conventionally processed samples. The stacks demonstrated a peak power of 7 W and constant power outputs of 0.5-3.1 W for 110-260 hours. This DL3DP can be expanded to manufacturing other heterogeneous ceramics for energy conversion and storage devices.

Figure 1