bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Understanding the Degradation of Oxide Ion Diffusivity in YSZ Electrolyte for Practical SOC
Authors: Kishimoto Haruo , Bai Qingchuan , Bagarinao Katherine Develos , Ishiyama Tomohiro , Yamaguchi Takuya , Yamaguchi Toshiaki 
Published: December 2024

Yttria-stabilized zirconia (YSZ) is the most common and the most reliable electrolyte material for solid oxide fuel cells (SOFCs) and solid oxide electrolysis cells (SOECs), collectively referred to as solid oxide cells (SOCs). Typical SOCs for practical applications are of the fuel-electrode-supported cell variety because these type of cells could be operated under high current densities. Here, the YSZ electrolyte is co-sintered with porous NiO-YSZ support at temperatures as high as 1400 °C to obtain dense electrolyte layer on the anode. In this process, NiO is expected to diffuse into the YSZ electrolyte. The influence of dissolved NiO into YSZ electrolyte has been investigated in AIST [1-3]. For the YSZ electrolyte with intentionally dissolved NiO, the phase transformation from cubic phase to tetragonal phase is accelerated in the lower oxygen potential range where NiO is reduced to Ni metal in the YSZ electrolyte, consequently, degradation in the conductivity of YSZ electrolyte occurs. In this study, the influence of co-sintering process of YSZ electrolyte with the NiO-YSZ support, i.e. NiO diffusion into YSZ electrolyte under co-sintering process, and its influence on the oxide ion diffusivity of YSZ electrolyte are examined.
YSZ electrolyte layers were prepared on the NiO-YSZ substrates by screen-printing method or dip-coating method, and then co-sintered at high temperatures between 1370 °C to 1550 °C. The co-sintered YSZ/NiO-YSZ half-cells were reduced under dry H2 flow for 5 to 300 hours. The crystal structure and Ni distribution of the YSZ electrolyte layer were analyzed using Raman spectroscopy and high-spatial-resolution SIMS (secondary ion mass spectrometry), respectively. Lastly, the oxide ion diffusivity of the YSZ electrolyte layer was obtained using the oxygen isotope exchange method and high-spatial-resolution SIMS technique.
By co-sintering of YSZ electrolyte and NiO-YSZ support, NiO uniformly diffused into YSZ electrolyte layer, and the amount of dissolved Ni (NiO) increased with increasing sintering temperature. When the half-cell was reduced at 900 °C, a phase transformation of the YSZ electrolyte was clearly observed, moreover, the oxide ion diffusivity of the YSZ electrolyte also decreased. By reduction of the half-cell at 700 °C, such phase transformation could not be observed, however, the oxide ion diffusivity is slightly but clearly decreased. In the presentation, the mechanisms of phase transformation and conductivity degradation will be discussed.

H. Yokokawa et. al., Fuel Cells, 19 (2019) 311–339.

T. Ishiyama, H. Kishimoto, K. D. Bagarinao, K. Yamaji, T. Horita, H. Yokokawa, ECS Transactions, 78 (2017) 321–326.

T. Shimonosono, H. Kishimoto, M.E. Brito, K. Yamaji, T. Horita, H. Yokokawa, Solid State Ionics,225, 69 (2012).
(Invited) Topsoe’s Vision on the Commercialization of Solid Oxide Electrolysis Cells: Challenges and Accomplishments in Upscaling to the MW Scale
Authors: Sala Elena Marzia , Hauch Anne , Padinjarethil Aiswarya Krishnakumar , Blennow Peter Gustav , Perin Giovanni , Rass-Hansen Jeppe , Heiredal-Clausen Thomas , Holstebroe Majken , Fittkau Birkmose Malte Frederik , Mai Andreas , Sune Thyden Karl Tor , Ebbesen Sune Dalgaard , Hultqvist Michael , Moses Poul Georg 
Published: December 2024

Topsoe is strongly committed to drive the decarbonization of the so-called hard-to-abate sectors, such as iron and steel manufacturing and long-haul transportation, by implementing the industrial scale production of sustainable fuels and chemicals via solid oxide electrolysis cells (SOECs).
To enable the upscaling of the SOEC technology at the pace required by the increasing green hydrogen demand and the company’s target of full climate neutrality by 2040, Topsoe is building a facility able to produce electrolysis stacks and modules with an annual capacity of 500 MW, equaling the production of 125,000 tonnes of hydrogen p.a. The construction of the production facility, covering an area of over 23,000 m2, was initiated at the end of 2022 in Herning, Denmark, and is progressing at an accelerated pace, aiming at full operation in 2025. The 2nd generation Topsoe Stack Platform (TSP-2) produced in the Herning facility consists of SOEC stacks designed for H2 production from the electrolysis of steam at pressurized conditions (>3 bar), while maintaining the ability to operate at ambient pressure to produce CO by CO2 electrolysis. The TSP-2 stack has a capacity of >15 Nm3 H2/h, to be further combined in a 12 stacks-core module totaling over 180 Nm3 H2/h.
Exciting and solid results have been recently released by Topsoe on the SOEC core’s first demonstration test at industrially relevant conditions [1]. The demo unit, consisting of 12 stacks (1200 cells) operating at a constant pressure of 3.5 bar and a combined stack power of 350 kW, showed remarkable stability over 2250 hours of operation (Figure 1). These impressive durability results were obtained at a core efficiency of approximately 93% (LHV of hydrogen), with an electricity consumption of the core of around 36 kWh/kg H2 and a ramp-up time to reach 100% of the load (approximately 230 A throughout each stack in the core) of just three minutes.
While providing an overview of the continuing demonstration tests ongoing at a stack and core level, this presentation will report the developments of the construction of the manufacturing facility in Herning, highlighting the major challenges and key factors playing a role in the large-scale commercialization of SOECs.

References:

[1] www.topsoe.com/blog/breakthrough-in-green-hydrogen-topsoes-soec-demo-reveals-strong-results. Last accessed on 18-04-2024.
Figure 1: Average cell voltage for all the 1200 cells in the 12 stacks of the Topsoe SOEC core’s demo unit as a function of time of operation.

Figure 1
(Invited) Ionic Nanoarchitectonics to Create Novel Functional and High-Performance Devices, Such As Neuromorphic Devices
Authors: Terabe Kazuya , Tsuchiya Takashi , Tsuruoka Tohru 
Published: December 2024

Many semiconductor devices are used in electronic information equipment, which is indispensable in today's information society. Progress in memory and computing functions through the integration of semiconductor devices has been supported by the development of ultra-fine processing technology, but there are concerns that this progress will slow down in the near future. In order to continuously improve the performance of electronic information devices, it is therefore necessary not only to further develop conventional semiconductor devices, but also to create innovative devices that operate according to new principles.
Recent years have also seen the development of hardware-oriented artificial intelligence (AI) technologies, such as brain-inspired computers that operate with low power consumption and small size. To realize such hardware-oriented AI systems, it is necessary to create devices with various unique functions, such as neuromorphic devices that mimic the structure and functions of the brain. These devices would include not only conventional semiconductor devices with properties suitable for digital arithmetic processing, but also devices with properties suitable for analogue arithmetic processing based on new operating principles.
Material properties are strongly influenced by small rearrangements and substitutions of constituent atoms. We have vigorously explored interesting nanophenomena and new functions arising from the control of nano- to atomic-scale ultrafine structures, such as small changes in atomic arrangement using ion transport [1-3]. This control of ultrafine structure can be achieved using ionic nanoarchitectonics methods, which allow local control of ion transport and electrochemical reactions occurring at solid interfaces and surfaces (Fig. 1). We have exploited various nanophenomena generated by this method to create ionic devices with electrical, magnetic and optical functions. In this talk, we will present various ionic devices created using ionic nanoarchitectonics, such as artificial vision devices that mimic the human retina to reproduce optical illusions, and decision-making devices that learn and make decisions on their own. In addition, ionic devices produced by ionic nanoarchitecture show promise for the development of hardware-oriented AI technology, the next generation of electronic information technology.

References: [1] K. Terabe, T. Tsuchiya, T. Tsuruoka, “A variety of functional devices realized by ionic nanoarchitectonics, complementing electronic components”, Advanced Electronic Materials, 8 (2022) 2100645. [2] K. Terabe, T. Tsuchiya, T. Tsuruoka, “Solid state ionics for the development of artificial intelligence components, Japanese Journal of Applied Physics, 61(SM) (2022) SM0803. [3] K. Terabe, T. Tsuchiya, T. Tsuruoka, “Atomic scale switches based on solid state ionics”, Advances in Physics: X, 7 (2022) 2065217.

Figure 1
Optimization of Reservoir Computing Utilizing Interfered Spin Waves
Authors: Nishimura Maki , Namiki Wataru , Nishioka Daiki , Terabe Kazuya , Tsuchiya Takashi 
Published: December 2024

Reservoir computing is a learning model that enables low-cost and fast learning compared to conventional deep learning. It enables physical implementation by replacing the reservoir part with a physical device that possesses nonlinearity, short-term memory, and high dimensionality. In particular, it was theoretically predicted that spin wave interference can perform highly efficient reservoir computing in micromagnetic simulations,[1] and it was experimentally verified by the present authors.[2] Whereas the computational performance was suggested to vary significantly depending on the interval of input voltage pulses used for spin wave excitation and the applied magnetic field intensity, the details were unclear to date. Therefore, we expanded the measurement range to investigate detailed mechanism of the system and to explore untouched high performance in the study.
We use a device fabricated on the surface of a single crystal, as shown in Fig. (a), then we performed one of the most important prediction benchmark tasks, the Nonlinear Autoregressive Moving Average (NARMA) model. Since it has been found that utilizing the nonlinear interference of spin waves through multi-detection demonstrates high performance, in this study, we utilized both Detection A and Detection B. We evaluated the prediction error of NARMA10, which requires short-term memory up to 10 steps, by varying the applied magnetic field and the interval of input voltage pulses under measurement conditions. As shown in Fig. (b), the comparison between the target waveform and the output waveform during training and testing under the conditions of a magnetic field of 182 mT and a pulse interval of 23.6 ns shows a good match, at that time, the error was 0.183 during the testing phase. Next, we examined the detailed condition dependence in NARMA10. As indicated in Fig. (c), high performance is obtained in the region where the pulse interval is between 20 and 30 ns, while the performance was low in the region below 19.3 ns, particularly in the strong magnetic field range from 188 mT to 200 mT. We will discuss the condition dependence with the other NARMA models like NARMA2. Additionally, we will discuss in detail the dependence on input pulse intervals, along with evaluations of short-term memory capacity and nonlinearity. This work was in part supported by Innovative Science and Technology Initiative for Security Grant Number JPJ004596, ATLA, Japan and JST PRESTO (JPMJPR23H4).
【Reference】[1] Nakane et al., IEEE Access
6, 4462 (2018).[2] Namiki et al., Adv. Intell. Syst.
5, 2300228 (2023).

Figure 1
Synthesis, Thermal Stability, and Proton Conductivity of Nam
1-X
Li1-X
H
x
(PO3)3·YH2o (M : Ni2+ and Mg2+)
Authors: Ishikawa Shota , Takahashi Haruya , Otsuka Keita , Ueta Naoya , Matsuda Yasuaki 
Published: December 2024

Mixed-cation phosphates are attractive materials as proton electrolytes covering the intermediate temperature range [1,2}. Depending on the combination of constituent elements, these materials exhibit various crystal structures with thermally stable tunnel-shaped frameworks and chains of water molecules arranged along PO4 tetrahedral chains, which act as pathways for proton diffusion. Among them, NaMg1-xLixHx(PO3)3・yH2O exhibits proton conductivity over 10-2 Scm-1 in 150-500°C [1]. Since crystal water is arranged using PO4 tetrahedral chains as a template, clarifying the correlation between the PO4 chain arrangement and proton conductivy is important for material design of new proton conductive phosphates. NaM1-x
Li1-x
H
x
(PO3)3·yH2O (M: Mg2+ and Ni2+) provides a crystal structure with a completely different arrangement of PO4 tetrahedra chains due to the variation in the M cation. In this study, aiming to develop a new proton conductor, NaNi1-x
Li
x
H
x
(PO3)3·yH2O containing Ni2+ (0.69 Å ) with an ionic radius smaller than Mg2+ (0.72 Å) was synthesized. Its thermal stability and proton conductivity were investigated and compared with NaMg1-xLixHx(PO3)3・yH2O.
Figure 1 shows the powder X-ray diffraction patterns for NaNi1-x
Li
x
H
x
(PO3)3·yH2O. Similar diffraction patterns to NaNi(PO3)3 [3] were observed for all compositions within the range of x = 0 – 0.2, with no reflections indicating impurity phases. All observed reflections were attributed to the crystal structure with space group Pcca, confirming the formation of a single phase with the NaNi(PO3)3-type structure in the new composition. In the range of x = 0 - 0.20, the shrinkage of the lattice corresponding to the change in composition was observed, and the formation of the solid solution was confirmed. In FTIR spectra, enhancement of the O-H and P-O-H peaks with increasing x were observed, which suggests that the introduction of protons as a charge compensation of the replacement of Ni2+ to Li+. Proton conductivity of NaNi1-x
Li
x
H
x
(PO3)3·yH2O measured by AC impedance method showed positive tendency for the proton contents. In the Arrhenius plot of NaMg1-xLixHx(PO3)3・yH2O, a competing behaviour was observed in which the increase in proton conductivity due to temperature rise and the decrease in the conductivity due to the desorption of crystal water. The highest conductivity was obtained for the sample with x = 0.20 and the value over 10-3 Scm-1 at 300°C. Details of conductivity and thermal properties will be discussed.
References
[1] N. Ueda, et al, Mater. Adv.,2, 6603 (2021).[2] Y. Matsuda, et al., Dalton Trans.
50, 7678 (2021). [3] F. Erragh, et al, Acta Crystallographica, Section C :
Crystal Structure Communications, 54, 1746 (1998).
Acknowledgment
This research was partially supported by Kanto Branch of the Electrochemical Society of Japan, JGC Saneyoshi Scholarship Foundation, JSPS KAKENHI Grant Number 24K08584 and 21K05246.

Figure 1
Effect of SOEC Operating Conditions on the YSZ Electrolyte Conductivity
Authors: Toriumi Hajime , Bagarinao Katherine Develos , Kishimoto Haruo , Yamaguchi Toshiaki 
Published: December 2024

Solid oxide electrolysis cells (SOECs) using the reverse reaction of solid oxide fuel cells (SOFCs) have attracted attention as green hydrogen production methods and H2O-CO2 co-electrolysis technologies. SOEC has an advantage of higher efficiency than other electrolysis technologies because it can utilize not only electrical energy but also thermal energy. Yttria-stabilized zirconia (YSZ) is often used for the electrolyte materials in SOECs. Generally, in fuel-electrode-supported SOECs utilizing YSZ electrolyte, the NiO-YSZ fuel electrode support and YSZ electrolyte are co-sintered at high temperatures in the range of 1300-1400 oC, so the NiO in the fuel electrode support inevitably diffuses into the YSZ electrolyte. It is known that the NiO dissolution into YSZ accelerates the YSZ conductivity degradation especially under reducing atmosphere, because the fast phase transformation from the cubic (higher conductivity) phase to the tetragonal (lower conductivity) one occurs via nickel reduction in the YSZ lattice [1,2]. Such conductivity degradation has already been well observed in YSZ bulk materials, but in the case of fuel-electrode-supported SOECs, the details of how the conductivity of the Ni-diffused YSZ electrolyte on the fuel-electrode support changes under the SOEC operating conditions are not clear.
In this work, in order to clarify the relationship between the conductivity changes of Ni-diffused YSZ electrolytes and SOEC operating conditions of the fuel-electrode-supported cells, we used the fuel-electrode-supported SOECs with Ni-diffused YSZ electrolytes via high temperature co-sintering process. The EIS data at 1.3 V are analyzed by fitting with an equivalent circuit to separate each resistance component. These results will be shown in this presentation.
This study is partly based on results obtained from a project, JPNP21022, commissioned by the New Energy and Industrial Technology Development Organization (NEDO).
References
[1] T. Shimonosono, et al., Solid State Ionics 225 (2012) 69-72.
[2] W.G. Coors, et al., Solid State Ionics 180 (2009) 246–251.
High Surface Proton Conductivity of Epitaxial CeO2-
δ Thin Film below Medium Temperature Range
Authors: Notake Go , Tani Minami , Yamada Mariko , Morizane Ryota , Tabuchi Riku , Higuchi Tohru 
Published: December 2024

Fluorite-type oxide such as Yttria-stabilized zirconia (YSZ) or doped-CeO2-
δ ceramics are good electrolyte candidates for solid oxide fuel cells (SOFC) due to their high oxygen ion conductivity in high temperature range above 700 ºC[1]. Furthermore, porous and nanocrystalline CeO2-
δ exhibit proton conduction at the surface below 100 °C[2]. This surface proton conduction is believed to the Grotthuss mechanism caused by the adsorption of water molecules. Since protons are produced by adsorbed water molecules and conduct through the layer of adsorbed water, oxygen vacancies and lattice constant are important parameters to enhance proton conduction. If high surface proton conduction can realize in CeO2-
δ thin film, this may be more suitable than porous or nanocrystalline materials for new electrochemical devices and smart fuel cells.
Recently, our group reported that the higher ion conductivity depends on the lattice constant and grain size for YSZ and Sm-doped CeO2-
δ thin films[3,4]. However, the effect of crystallinity on the ion conductivity is not clarified. In this study, we have prepared the CeO2-
δ thin films on YSZ (002) substrates by RF magnetron sputtering and probed their surface proton conduction below 300 °C in terms of electrical conductivity and electronic structure.
The CeO2-
δ ceramics target was prepared by solid-state reaction method. The CeO2-
δ thin films with thicknesses of ~20 and ~120 nm were prepared by RF magnetron sputtering by adjust the deposition time. The sputtering conditions is followed; The base pressure was kept at 5.0×10-8 Torr and the deposition pressure was kept at 3.5 mTorr to control the Ar flow rate of ~2.67 sccm. The RF power was fixed at 30 W. The crystal and electrical structure of CeO2-
δ thin films were evaluated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (PES) and X-ray absorption spectroscopy (XAS). The electrical characteristics was evaluated by A.C. impedance method.
The prepared CeO2-
δ thin films on the YSZ substrates were due to the exhibited 200 and 400 peaks. Figure shows the Arrhenius plot of the conductivity of the as-deposited and wet-annealed CeO2-
δ thin films, indicating thermally activated behavior in the medium temperature range but different behavior below 100 °C. The conducting carrier in the medium and room temperature range is considered to be oxide ion and proton, respectively. In this poster, we will show that the surface proton conduction of CeO2-
δ thin film is closely related to the lattice distortion and oxygen vacancies concentration at the surface.
References
[1] Eguchi, et. al., Solid State Ion.
52, 165, (1992).
[2] Shirpour, et al., Phys. Chem. Chem. Phys.
13, 937, (2011).
[3] Takayanagi, et. al., Solid State Ion.
311, 46, (2017).
[4] Nishioka, et. al., Nanoscale Res. Lett.
15, 42, (2020).

Figure 1
Preparation of Y2O3-Stabilized ZrO2 Film By Warm Isostatic Press (WIP) Method for Metal-Support Solid Oxide Fuel Cells (SOFCs)
Authors: Nakagawa Niki , Song Jun Tae , Watanabe Motonori , Inada Miki , Ishihara Tatsumi 
Published: December 2024

Solid Oxide Fuel Cells (SOFCs) are attracting as highly efficient power generator and almost no air pollutant emitted. So, SOFCs are now practically used, however, current SOFCs are consisted of all ceramics and so reliability and cost are the issues. Metal support SOFC (MS-SOFCs) is used porous metal for substrate and so high mechanical strength and also easy gas sealing is expected. However, preparation of dense electrolyte film on porous metal substrate is now the most significant issue to solve. In this study, we proposed oxide dense plate of NiO-NiFe2O4 as precursor of MS-SOFCs and after deposition of dense electrolyte film, dense oxide disc of NiO-NiFe2O4 is changed to porous Ni-Fe porous support by reduction in H2 stream[1]. For making thin film of Y2O3 stabilized ZrO2(YSZ), warm isostatic press (WIP) was used by using YSZ tape prepared by tape casting method.
Commercial YSZ powder (TOSOH TZ8Y) was used after ball mill treatment and after making slurry, YSZ green sheet was obtained by tape casting of YSZ slurry on plastic film and then the obtained YSZ film was transcribed onto NiO-NiFe2O4 substrate with warm isostatic press (WIP) at 353K. After co-sintered at 1473K for 6 h, dense YSZ film with 10mm was obtained followed by reaction in H2 stream at 973K. Sm0.5Sr0.5CoO3 was used as cathode. After reduction, change in size and porosity of NiO-NiFe2O4 were less than 6% and 39%, respectively.
Figure 1 shows power generation property of the obtained Ni-Fe supported YSZ cell at 973 K. The open circuit potential was closed to the theoretical value of 1.03 V and reasonable power density of 340mW/cm2 was achieved at 973K. Slightly lower OCV may be results of Fe diffusion into YSZ cell and so, functional inter layer to prevent elemental diffusion was also investigated in this study. This study reveals that metal support YSZ can be obtained by WIP method.
Acknowledgement; This study was financially supported by New Energy and Industrial Technology Development Organization (NEDO,JPNP20003), Japan

Ju, Y‐W., S. Ida, and T. Ishihara. Fuel Cells6 (2012): 1064-1069.

Figure 1 Power generation curves of metal support SOFC using YSZ film prepared with WIP method.

Figure 1