bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Corrosion Behavior and Hydrogen Permeation of Steel Materials Under Wet-Dry Cyclic Environment
Authors: Katayama Hideki , Katsumura Toshiki , Akashi Takaya 
Published: December 2020

Higher strength steels have been required from the viewpoint of safety and energy saving in the fields of transportation equipment and infrastructure. However, it is known that the higher the strength of steels, the higher the risk of hydrogen embrittlement. It has been reported that hydrogen embrittlement occurs even in atmospheric corrosive environment, and solving the problem of hydrogen embrittlement will be the key to the future hydrogen energy society. For that purpose, it is necessary to clarify the hydrogen embrittlement behavior due to atmospheric corrosion. We focused on surface potential measurement as a technique to visualize permeated hydrogen. The purpose of this study is to clarify the hydrogen permeation behavior of steel materials under atmospheric corrosive environment.
A 50 x 50 x 0.5t mm of pure iron plate was used as the sample. After grinding both surfaces of samples and degreasing with ethanol, nickel plating was applied to the hydrogen detective side of the sample. Hydrogen penetration was accelerated by a wet-dry cyclic corrosion test using a droplet of 0.5 M NaCl solution. The distilled water was added after second cycles to avoid the accumulation of NaCl. The potential of the hydrogen detective surface was measured with time in the drying process by surface potential device. The surface potential probe is set on the XY stage and the surface potential distribution can be obtained by scanning the probe. In this study, the surface potential of the copper plate in contact with the sample was adjusted at 0V as the reference potential.
Although the corrosion occurred on the surface in the drying process after dropping the NaCl solution, no surface potential change was observed on the hydrogen detective side of the sample in that process. The surface potential started to change in a part of the surface of the sample immediately after the droplet was completely dried, and after 1hour, the size and shape of the potential changed area became almost the same as those of the corrosion products. No corrosion occurred on the hydrogen detective side of samples during the surface potential measurement, indicating that the surface potential change is attributed to the atomic hydrogen penetrated through the samples. The surface potential changed area gradually disappeared, and almost no potential change was observed on the surface after 72 hours. The change in surface potential after the second cycle of wet and dry cyclic corrosion test showed the same tendency as in the first cycle, and a potential distribution close to the shape of corrosion products was observed.
Evaluation of Corrosion Resistance of Steel Materials By Hyperspectral Analysis of Corrosion Products
Authors: Kobayashi Ryo , Katayama Hideki , Akashi Takaya 
Published: December 2020

Direct visual inspection at short range and hammering test every five years are obligatory for inspection and evaluation of bridges in Japan. However, simple and quantitative inspection techniques are required due to issues such as a shortage of bridge inspectors and a lack of inspection cost. We focused on the spectrum analysis by a hyperspectral camera as a new tool to evaluate corrosion resistance. The purpose of this study is to investigate the feasibility of evaluating the corrosion resistance of steel materials by hyperspectral analysis of corrosion products.
α-FeOOH, β-FeOOH, γ-FeOOH and Fe3O4 were used as the samples of standard iron corrosion products. These corrosion products were set on the sample holder, and the spectra were taken by a hyperspectral camera using halogen lamps as a source of irradiation light. The average spectrum obtained at almost the center of the sample was analyzed.
The reflection spectra were observed at 595 nm and 770 nm for α-FeOOH, 745 nm for β-FeOOH, and 790 nm for γ-FeOOH, respectively, and Fe3O4 showed a low reflection spectrum. This means that different corrosion products can be identified from the reflection spectrum. In addition, the spectrum analysis was conducted for the corrosion products formed on the sample exposed in coastal area for six months. The peaks in the spectrum were correspondent with them observed in the spectra of the standard iron corrosion products. The spectrum analysis by a hyperspectral camera can be powerful tool to evaluate the corrosion performance of steel materials.
Modeling, Validation, and Application of Finite Element Models for the Galvanic Corrosion of Aluminum Alloy 6061-T6 Coupled to Non-Passivating and Passivating Alloys
Authors: Wohner Natalie , Smith Cody Troy , Hihara Lloyd H. 
Published: December 2020

Galvanic corrosion of aluminum alloys coupled to non-passivating and passivating alloys exposed in corrosive environments can cause severe corrosion damage in marine structures. The aim of this study is the development of a finite element model using COMSOL Multiphysics to predict the galvanic interaction of aluminum alloy AA6061-T6 coupled to noble materials.
The numerical model is based on anodic dissolution kinetics of AA6061 and cathodic kinetics of Ti6Al4V, 316 stainless steel, and copper determined with potentiodynamic polarization. The model predicts that the cathodic material and the geometry of the galvanic couple both influence the corrosion rate of AA6061, and that the solution composition locally changes over time.
In order to account for the time-dependent change in solution chemistry a thorough experimental investigation of the effect of pH and chloride ion (Cl-) concentration on the corrosion kinetics of AA6061 is presented using potentiodynamic polarization. Corrosion kinetics were obtained in sodium sulfate and sodium chloride solutions as a function of pH and chloride ion concentration and implemented in the numerical model.
The validation of the model is in progress and will be compared to data of actual galvanic couples exposed in the laboratory and in different atmospheric environments.

Acknowledgement:

This material is based on research sponsored by the USAFA and University of Hawaii under agreement number FA7000-18-2-0004. The U.S. Government is authorized to reproduce and distribute reprints for Governmental purposes notwithstanding any copyright notation thereon.
Corrosion Behavior of Rusted Carbon Steel Coated with Reactive Paint Under Wet and Dry Cyclic Condition
Authors: Takahashi Masamitsu , Tsuchiya Hiroaki , Hanaki Koushu , Yamashita Masato , Fujimoto Shinji 
Published: December 2020

Degradation of steel infrastructure built in 20th century is seriously progressing. This deterioration is mainly caused by corrosion of steel in atmospheric environments that contain O2 and H2O. To ensure long-term reliable service of steel infrastructures, some measures to retard the atmospheric corrosion of steel structures must be applied.
Among several measures, paint coating is widely employed for corrosion protection of steel infrastructures. However, paint coating layers applied over steel infrastructures are subjected to degradation, and therefore need to be repaired by reapplication of the paint coating. Even after the reapplication, steel substrate under the coating is prone to corrode, accompanied with formation of rust layer which accelerates corrosion even under the coating since rust layer acts as an oxidant. Therefore, simple reapplication of a conventional paint coating over the rusted steel is insufficient. It is desired to reduce the corrosion acceleration effect of rust, and moreover to increase the protectiveness of rust layer underneath the coating.
In the atmospheric corrosion environment, four types of crystalline rusts can be produced; alpha-FeOOH, beta-FeOOH, gamma-FeOOH, and Fe3O4. The composition of the rust layer is acknowledged to exert a significant influence on corrosion resistance of steels. Thus, it is an interesting challenge to enhance corrosion protectiveness of the rust layer by reapplication of a sophisticated paint coating to the rusted steel structure. In this study, corrosion protection performance of the reactive paint coating, which is designed so as to modify the protectiveness of rust layer, applied over a rusted carbon steel is discussed.
It was found that the reactive paint coating worked well to reduce corrosion damage of the rusted carbon steel. After 4,320 h cyclic corrosion test according to JIS K5600-7-9, a large amount of rust flow and swelling of the paint coating layer around the crosscut damage made in advance in the coated surface were detected for the conventional heavy-duty coating specimen. In contrast, very small flow of rust or swelling around the crosscut damage was detectable for the reactive paint coating specimen, implying that corrosion propagation from the residual rust on the steel surface was effectively suppressed by the reactive paint.
Electrochemical analyses revealed that the reactive paint coating applied over the rusted carbon steel greatly reduced corrosion current density of the steel, compared to the conventional heavy-duty coating. This low corrosion rate of the rusted steel covered with the reactive paint is found to be attributed to the modification of rust structure.
(Battery Division Technology Award Address) Exploring Stable Manganese-Based Oxides As Cathodes for Na-Ion Batteries
Authors: Yang Yong , Zuo Wenhua , Liu Xiangsi 
Published: December 2020

Sodium ion batteries (SIBs) promise the potential for large-scale grid storage, due to the high abundance and wide distribution of Na sources as compared to their lithium counterparts.1-3 Among various sodium storage cathodes, layered sodium transition metal oxides (NaxMnO2) have gained significant attention owing to their great variety of compositions, ease of scalable preparation and high reversible specific capacity.
In the last several years, we have utilized different strategies such as alivovalent doping, ALD coating and controlled thermal treatments to synthesize several series of P2-type Mn-based cathodes materials and obtained promising results for future development[2-5]. For example, we propose an effective and synergetic strategy in combination of liquid N2 quenching and aliovalent doping to get new layered cathode materials [5]. As evidenced by X-ray diffraction, neutron diffraction and solid-state 23Na nuclear magnetic resonance techniques, the results reveal the significance of manipulating transition metal ions vacancies and valences to the electrochemical performance of P2-type Mn-based materials. Our results demonstrate that such a new structure significantly enhances the deliverable capacity, Na+ mobility and electronic conductivity of the materials. Furthermore, the effects of aliovalent doping elements and cooling approach on the long-range structure, local environment and electrochemical performance are comprehensively studied by comparing 15 sets of Na0.67MxMn1-xO2 materials (M = Al, Fe, Mg, Li ). The optimized Na0.67Al0.1Fe0.05Mn0.85O2 material exhibits a remarkably high initial capacity of 202 mAh g-1 among ever reported P2-type layered oxides within 2-4 V, a stable capacity retention of 81% after 600 cycles and outstanding rate capability of the specific capacity up to 122 mAh g-1 at 1200 mA g-1. In addition, some work about the air-stability of these oxides materials will be also presented.
References:

N. Yabuuchi, K. Kubota; M. Dahbi, S. Komaba, Chemical Reviews
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114 (23), 11636-11682

X.H.Wu, Y. Yang et al; J Power Sources, 2015，281，18-26

X.S. Liu, W. H. Zuo, Y. Yang, et al, Angrew Chemie.; 2019，58，18086

W.H. Zuo, J.Q. Qiu, Y. Yang, et al; Energy Storage Materials; 2020，26，503-512

Xiangsi Liu, et al; submitted
Plasmonic Ag/N-doped Graphene Nanoflakes as Electrocatalyst for Oxygen Reduction Reaction Enhanced by Solar Energy
Authors: Wang Zhihuan , Chen Yingjie , Gong Chong , Sui Lina , Yu Liyan , Dong Lifeng 
Published: December 2020

Oxygen reduction reaction (ORR) is a crucial cathodic reaction for fuel cells. Due to its sluggish kinetics, various ORR electrocatalysts have been designed and extensively investigated. Traditionally, Pt-based materials serve as efficient ORR catalysts. However, Pt’s low abundance, high cost and poor durability have compelled people to explore other materials. For example, silver (Ag) is comparatively well-stocked and low-cost, which has drawn great attention. Although Ag shows exceptional anti-poisoning property, it is not good as Pt. Recently, enhanced electrochemical behavior of plasmonic nanostructures under illumination has been examined through both theoretical modeling and experimental investigations. As a green and sustainable energy source, solar energy can be efficiently introduced into fuel cells and metal-air batteries. Plasmonic Ag nanoparticles have strong spectral absorption in the ultraviolet and visible light bands due to unique localized surface plasmon resonance effects. Meanwhile, nitrogen-doped graphene (NG) incorporates nitrogen (N) atoms into graphene skeleton through a hydrothermal process, thereby providing active ORR sites. Also, the vacancies and defects generated by the N-doping allow silver nanoparticles to be better dispersed on the graphene as well as maintain silver nanoparticles during the reaction.
Herein, plasmonic Ag nanoparticles decorated N-doped graphene (Ag/NG) were synthesized and utilized as ORR catalysts. The ORR performance of Ag/NG greatly exceeded that of pure Ag nanoparticles and NG. For instance, the half-wave potential was 0.86 V, exceeding that of commercial Pt/C (20 wt. %). Under the AM1.5G simulated sunlight, Ag/NG demonstrated photo-enhanced electrocatalytic performance with right shifting of onset potential and enhanced current density. Therefore, the Ag/NG composite provides a potential strategy for the development of solar-enhanced electrocatalysts for fuel cells and metal-air batteries.
Capacitance Measurement of Cerium Oxide Thin Film Capacitors
Authors: Kusafuka Kazuki , Kakushima Kuniyuki 
Published: December 2020

Introduction
Cerium oxide (CeOx) is an attractive material for large volume on-chip decoupling capacitors, owing to its high dielectric constant (k) of 28. Commonly, a definite frequency dispersion in the small-signal capacitance measurement is observed in the frequency sweep, and larger capacitance values can be obtained at low frequency in the kHz range. The dielectric relaxation is reported to originate from the interface polarization between the polycrystalline grains in the films. In this work, the thickness-dependent polarization and the capacitance measurement under a DC voltage application are characterized.
Fabrication process
CeOx films with thicknesses from 8 to 20 nm were deposited by e-beam evaporation on an n+Si substrate with a W layer atop. Another W layer was deposited on CeOx layers and patterned to form electrodes. After the Al back contact formation, the samples are annealed at 420oC.
Results
Fig. 1 shows the frequency dispersion of the capacitors with different CeOx thicknesses measured at 0 V. The dielectric relaxation frequency shifts to higher frequency while thinning the thickness, which is useful for capacitor application. The transient current upon 1 V application is shown in fig. 2. After a high charge current, one can observe a decay in the transient current, indicating the delay in the polarization. The capacitance of the samples can be obtained by taking the integral of the charge current and is shown in fig. 3. Comparable capacitance values were obtained with the small-signal measurements. 2 to 3 times higher capacitance values can be achieved with respect to the ionic polarization.
Conclusion
High capacitance values measured in the small-signal setup were confirmed by direct current measurement by DC voltage application. An even higher capacitance can be obtained with the thinner film.
(Invited) Composition and Interfacial Engineering of Lithium Iron Orthosilicate Cathodes with Superior Intercalation Properties
Authors: Demopoulos George P. , Zeng Yan , Rasool Majid , Zaghib Karim 
Published: December 2020

The quest for Li-ion batteries (LIBs) delivering higher energy density while being safer and sustainable has intensified recently. This work presents our advances towards improving the intercalation properties of an important cathode material, Li2FeSiO4(LFS), in order to take advantage of its attractive properties in terms of sustainability and safety. LFS theoretically has 330 mAh g-1capacity (2 Li+ per formula unit), however, inherently it exhibits relatively poor Li-ion intercalation kinetics, interfacial reactivity and complex phase transitions resulting in lower than one Li+ storage and poor capacity retention.In this work, we apply a multi-prong strategy to overcome these obstacles making use of compositional engineering to tune the electronic and crystal structures of LFS in concert withmechanochemical processing and polymer coating to provide a stabilizing interphase. We take advantage of the versatility of hydrothermal synthesis [1a] and mechanochemical activation and synthesize various cation-substituted and non-stoichiometric LFS nanomaterials with annealed orthorhombic Pmn21structure. Firstly, mechanochemical annealing leads to activation of Li-ion diffusion (DLi) by one order of magnitude enhancement [2a,b]. Secondly, partial substituting Co for Fe is found to allow faster phase transformation from pristine Pmn21to inverse Pmn21with important positive ramifications in its cycling performance [1b]. Thirdly, we boost the capacity of LFS, bydesigning Fe-rich (and not Li-rich!) LFS materials that deliver higher capacity within a reasonable voltage window [1c]. Lastly, PEDOT coating and near the surface composition alteration allows for stable cycling performance with >1.2 Li capacity [2c].
Acknowledgments:This research was supported by a NSERC grant and the McGill Sustainability Systems Initiative (MSSI).
References:
[1] Yan Zeng et al., (a) Hydrothermal Crystallization of Pmn21Li2FeSiO4Hollow Mesocrystals for Li-Ion Cathode Application,Chem. Eng. J., 359 (2019), 1592-1602; (b) Unveiling the mechanism of improved capacity retention in Pmn21Li2FeSiO4 cathode by cobalt substitution, J. Materials Chem. A2019, 7, 25399 – 25414; (c) Defect Engineering of Fe-Rich Orthosilicate Cathode Materials with Enhanced Li-Ion Intercalation Capacity and Kinetics, ACS Applied Energy Materials, 2020, 3, 675−686
[2] Majid Rasool et al., (a) Mechanochemically-tuned structural annealing: a new pathway to enhancing Li-ion intercalation activity in nanosized βIILi2FeSiO4
, J Mater. Chem. A 2019, 7, 13705 – 13713; (b) Unusual Li-ion intercalation activation with stepwise capacity increase in orthosilicates, J. Phys. Chem. C;DOI: 10.1021/acs.jpcc.9b11896; (c) PEDOT encapsulated and mechanochemically engineered silicate nanocrystals for high energy density cathodes, Advanced Materials Interfaces, 2020, 2000226; DOI: 10.1002/admi.202000226
Thermodynamics and Kinetics of LiCoO2/Graphite Commercial Battery
Authors: Mao Jing , Liu Xin 
Published: December 2020

With the energy density increase of lithium-ion batteries in electric vehicles, people pay more and more attention to safety issues. The heat generation is the main factor affecting the safety. When the lithium-ion battery is overcharged, the so-called thermal runaway will occur in the battery system. In the process of thermal runaway, the temperature of battery increases due to exothermic reaction. In turn, the increased temperature accelerates these degradation reactions and makes the system unstable.
In this paper, we use LiCoO2/graphite commercial battery with assumed uniform heating to study the relationship between the kinetics and thermodynamics of electrode reaction and the function of magnification and temperature by means of electrochemical test. The results are used to estimate the heat production rate, which is related to the ohmic resistance of the LCO electrode, the charge transfer and transfer limitation of SEI film, and the entropy of the electrode reaction. After that, the kinetic and thermodynamic characteristics of the electrode are given. Then, the dependence of different heat sources on magnification and temperature are shown. Finally, the total heating rate of LCO electrode is calculated, and the importance of different individual contributions is discussed.
The results show that all the individual heat sources contribute significantly to the total heat in the electrode. The heat source is a function of magnification, temperature and lithium concentration in the active material. Compared with IR drop, the heat generated due to transfer restriction has a greater impact on irreversible heat. When the concentration of lithium ion is small, the irreversible heat accounts for the main part of the total heat. When the concentration of lithium ion is large, the reversible heat accounts for a large proportion of the total heat, but the difference between the reversible heat and the irreversible heat is not significant.
Study of Cu Replacement in Na2Ti1-XTMXO3 Na-Rich Cathode Material for High Capacity and Superior Stability
Authors: Ganesan Bala Krishnan , Balasubramaniam Ramkumar , DongWook Kim , Moorthy Megala , Seol Jaechang , Lee Seon Yeong , Lee Yun-Sung 
Published: December 2020

Sodium ion batteries are considered as a cost effective and promising alternative to lithium ion batteries for next generation large scale energy storage applications. However, the sluggish intercalation kinetics and poor stability plagues the efficient applications.[1] Recently sodium rich cathode materials are emerging as a promising system to retain high specific energy with improved durability. Benefiting from the stabilizing property of other transition metal [TM = Cu, Cr] , the same is used as a substitute in Ti site and improved stability have been achieved. [2] In this work, we developed a high performing doped cathode of Sodium Titanium Oxide (Na2TiO3) as a battery positive electrode. The highly favorable architecture in both the electrodes showed an enhanced capability towards ion storage. A high energy retention at high power condition along with high stability have been achieved.

References:

[1] J. R. Miller, P. Simon, Science
2008, 321, 651.
[2] R. Thangavel, B. Moorthy, D. K. Kim, Y. S. Lee, Adv. Energy Mater. 2017, 1602654
Keywords : Sodium Ion Capacitors; Graphene; Energy Density; Stability; Ragone Plot