bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure of the Oxide Films Formed on Hydrogen-Charged and Uncharged 316L Stainless Steels in Oxygenated High Temperature Water
Authors: Cui Tongming , Zhang Kun , Ma Jiarong , Jia Yibo , Ning Fei , Lu Zhanpeng 
Published: February 2020

Austenitic stainless steels (SSs) are commonly used in pressurized water reactors (PWRs) nuclear power systems as key structural materials. The corrosion resistance are closely related to the passive film formed on the surfaces of austenitic alloys in high-temperature aqueous environments. It has been reported that hydrogen can affect corrosion, localized corrosion as well as stress corrosion cracking of materials in aqueous solutions. It is necessary to investigate the influence of hydrogen on the corrosion behavior of stainless steels material in high temperature water environments. In the present study, the oxide films formed on 316L SS with uncharged (316L) and hydrogen-charged (316L-H) in oxygenated simulated PWR primary water at 300℃were investigated. Oxygen was added in high temperature water to simulated occlude region condition or faulted water chemistry. The aim of this work is to clarify the effect of hydrogen in stainless steel on the corrosion behavior.
The surface morphologies of the oxide films formed on 316L (uncharged) and 316L-H (charged) specimens after exposure to oxygenated PWR primary water at 300 oC for168 h were observed. The regular and irregular oxides particles homogeneous distributed on the outer surface of 316L specimen, and compact filamentary oxides in the sub-surface. On 316L-H specimen, large oxides dispersed and inhomogeneous distributed on the outer surface, and compact minor polyhedral oxide particles packed on the sub-surface. The number of the large oxides on the outermost surface of 316L specimen was more than that on the 316L-H sample. The cross-section of the oxide films formed on 316L specimens after exposed to oxygenated PWR primary water was analyzed by FIB-TEM. The interface front between the inner oxide layer and the base metal was wavy-shaped. There were compact Cr-rich oxides in the inner layer, and filamentary (Fe, Ni)-rich oxides in the outer layer. There was slightly Ni-enrichment near the inner oxides/matrix interface and Fe-enrichment beneath the inner oxides/matrix interface from EDS line scan profile.
Some discontinuous cellular oxides distributed on the inner oxides/matrix interface on 316L-H after the exposure test, which was Fe-rich oxides identified by EDS maps and line scan. Similar to the 316L specimen, the inner layer oxide was compact and Cr-edriched, showing a slightly Fe-enriched beneath the inner oxides/matrix interface, but no Ni-enrichment close to the interface of inner oxides/matrix was observed.

Figure 1
(Invited) Recent Advances in SiC CMP
Authors: Rhoades Robert L. 
Published: February 2020

The need for high-quality single crystal SiC substrates continues to grow as the demand for SiC-based power and RF devices increases. The physical properties of SiC result in better thermal conductivity, higher breakdown voltage, faster switching performance and lower resistivity when compared to similar devices based on silicon. Even with the performance advantages, the adoption rate of SiC is slowed by high cost and inherent difficulty of processing the material. Conventional processing of SiC substrates involves double-sided batch lapping followed by batch diamond polishing then final polishing with a non-diamond slurry to achieve an epi-ready surface. This process flow involves multiple process tools and is fraught with issues including the need for wafer sorting to group wafers by thickness, manual loading and unloading of wafers, low yields, and unacceptable risk of batch loss (an entire batch of wafers may be scrapped if even one wafer cracks or breaks during process).
This paper presents an improved process for single-wafer CMP during SiC substrate manufacturing or backside thinning. In contrast to batch polishing, key improvements include individual wafer processing, fully-automated handling, and elimination of the need for wafer sorting and grouping by thickness. Recent development efforts have achieved removal rates for the 4H Si face up to 2.5 µm/hour for the first step CMP. Removal rates for the C-face can be as much as 3-4x higher consistent with other findings in the industry. Fig 1 shows surface finish after the polishing sequence is complete which is consistently at or below 1 Å Ra as measured by AFM. The combination of an optimized grind followed by an optimized CMP process provides a viable path to both improving wafer yield and reducing costs for SiC wafer manufacturing or backside thinning process sequences.

Figure 1
Capacitive Deionization Using Activate Carbon Electrodes Obtained from Different Precursors
Authors: Barcelos Kamilla Malverdi , Zornitta Rafael Linzmeyer , Ruotolo Luis Augusto Martins 
Published: February 2020

Capacitive deionization (CDI) is a promising technique for brackish water desalination and water softening. It has been recognized that its performance is strongly dependent of the electrode properties such as specific surface area, pore volume, pore size distribution, and surface functional groups. Carbon is main material that fits all these requirements, allied to its lo high capacitance, conductivity, and low cost. Here, we present a comparison of the different activated carbons (AC) prepared in the Laboratory of Environmental Technologies using sugarcane bagasse fly ash (BFA)1,2, polyaniline activated carbon (PAC)3,4, and lignin activated carbon (LAC)5. Electrodes prepared with these materials were used in symmetric (SY) and asymmetric configurations (ASY)4,5, and in membrane CDI (MCDI)4 as well. The best result was achieved using PAC electrodes prepared applying 500 oC as carbonization temperature. In this case, maximum adsorption capacity was 22.2 mg of NaCl removed per g of electrode, which is among the highest values reported in literature.
References:

Lado et al. (2016) J. Appl. Pyrolysis 120, 389.

Lado et al. (2017) J. Appl. Pyrolysis 126, 143.

Zornitta et al. (2017) Carbon 123, 318.

Zornitta and Ruotolo (2018) Chem. Eng. J. 332, 33.

Zornitta et al. (2018) ChemSusChem 11, 2101.
Electrodeposition of Aluminum Using Chloroaluminate Ionic Liquids Under Dry Air Conditions
Authors: Miyake Masao , Hirata Mizuki , Hirato Tetsuji 
Published: February 2020

Electrodeposition of Al at near room temperature using chloroaluminate ionic liquids, represented by the 1-ethyl-3-methylimidazolium chloride−AlCl3 system, has been extensively investigated as a technique for the fabrication of Al coatings. Such coatings have many potential applications, e.g., as corrosion-protective and decorative coatings. The electrodeposition of Al is usually performed under an inert gas atmosphere such as nitrogen and argon in a closed system using a glove box to protect the bath from absorbing moisture. Exposure of chloroaluminate ionic liquids to ambient air readily causes hydrolysis, which makes Al electrodeposition impossible. However, operation in a closed system reduces the productivity and increases the cost of the electrodeposition process, making it unsuitable for a large-scale production in industry.
In this study, the feasibility of the electrodeposition of Al using chloroaluminate ionic liquids under dry air conditions was examined. Such dry air conditions can be maintained in a system that is half-open to ambient air using a dehumidifier. As the electrodeposition process in dry air does not require the use of a glove box, it should be much more productive than in inert atmosphere.
Four kinds of chloroaluminate ionic liquids composed of different organic cations ([cation]Cl−AlCl3) with a molar ratio of [cation]Cl:AlCl3 = 1:2 were employed as the bath for Al electrodeposition. The cations employed were 1-ethyl-3-methylimidazolium, 1-butylpyridinium, 1-butyl-1-methylpyrrolidinium, and trimethylphenylammonium. Electrochemical behavior of Al in these baths in dry air was examined by cyclic voltammetry. Galvanostatic electrodeposition was performed and deposits from these baths in dry air were inspected by X-ray diffraction, scanning electron microscopy, and elemental analysis. The current efficiency was also assessed. These experiments clarified the baths that can produce Al films in dry air with as good quality as the ones obtained in an inert atmosphere. The reactivity between the organic cation and superoxide ion generated by the cathodic reduction of dissolved oxygen seemed to be responsible for the difference in the quality of the Al films electrodeposited from these baths in dry air. The reactions of dissolved oxygen in these baths are discussed.
Modeling the Effect of Layer-on-Layer Cathodes in Lithium-Sulfur Batteries
Authors: Shebert George Leonard , Zhang Rui , Joo Yong Lak , Zamani Somayeh 
Published: February 2020

Lithium sulfur (Li-S) batteries are promising candidates for next-generation energy storage due to their high theoretical energy density and environmentally abundant chemical inputs. However, well-known challenges such as polysulfide crossover, large volume changes during cycling, and deposition of insulating lithium sulfide limit the capacity and capacity retention of Li-S batteries. A popular approach to address these issues is to control the structure and properties of the carbon cathode in order to influence the transport of polysulfides, surface area for reaction, and lithium sulfide deposition.
Towards this direction, we developed a layer-on-layer cathode structure with sulfur-impregnated activated carbon alternating with graphene. The layered structure exhibits improved capacity over the control at low rates but the benefits diminish at high rates and high graphene loadings. To explain this behavior, we use a 1-dimension + time numerical continuum model for the Li-S full cell which is validated against experimental data. The model includes the electrochemical reactions and precipitation of sulfur and intermediate polysulfide species, transport of species through the battery, lithium sulfide nucleation and growth, and adsorption of polysulfides. Experiments and simulations suggest that a combination mass-transfer limitations and surface passivation effects is crucial in describing the performance of the cells, and the effect of cathode properties is further investigated using the model.
In-Situ Electrochemical Formation of Na1+XCu3-XO2 for Cathodes in Sodium Ion Batteries.
Authors: Juarez-Yescas Carlos , Ramos-Sánchez Guadalupe , González I 
Published: February 2020

In recent years, there has been increasing interest in developing high capacity Na intercalation batteries1-3, mainly because of their similar chemical behavior as Li-ion batteries, low cost of raw materials and abundance of sodium in the earth’s crust. A material of interest for Na-ion batteries is Na2CuO2 with a high theoretical capacity (379 mAh/g and 189 mAh/g, corresponding to 2 and 1 Na ions intercalated). Na2CuO2 has been hypothesized to exist, analogous to the already reported lithium cuprate4 (Li2CuO2); however, it has never been reported. In this work, the NaCuO2 phase is first synthesized through a solid state reaction, with the aim of carrying out further in-situ electrochemical modifications to obtain the Na2CuO2 phase. Preliminary results have shown reversible electrochemical properties of the NaCuO2 phase, upon electrochemical reduction the Na1+xCu3-xO2 (0<x≤1) phase is most likely formed around 1.5 V (vs Na0/Na+ ), Figure 1. A. During galvanostatic cycling, in a voltage window of 1.5-4 V, reversible capacities of 15 mAh/g are achieved, Figure 1. B; however, in a wider potential range (0.7 V to 4.2 V) the first charge cycle reaches capacities of 120 mAh/g, unfortunately fading in subsequent cycles. The capacity fade is partly attributed to the presence of impurities formed during the synthesis of the NaCuO2 phase (primarily CuO and NaOH). Several strategies are carried out to increase the purity of NaCuO2, for instance, improving reactant contact and determining the ideal reaction temperature; on the other hand, further structural characterization is performed to determine the species formed during the reduction of NaCuO2 (e.g. XRD in-situ).
This project has been performed with the financial support from Conacyt PN2016 Project 2551 and SECITI SECITI/080/2017 and C. Juarez-Yescas acknowledges the Postgraduate grant from Conacyt.
Figure 1. A) typical voltammograms (v=0.01 mV/s) and B) charge – discharge curves obtained for 𝑁𝑎0 | 1𝑀 𝑁𝑎𝑃𝐹6 (𝐸𝐶:𝐷𝐶) | 𝑁𝑎𝐶𝑢𝑂2:𝐶𝑆𝑃:𝑃𝑉𝐷𝐹. The charge – discharge curves were obtained at 0.1 C.

References

Vaalma, C., Buchholz, D., Weil, M. & Passerini, S. Nat.
Rev. Mater.
3, (2018).

Kim, H., Kim, H., Ding, Z., Lee, M. H. & Lim, K. Adv. Energy Mater. 1–38 (2016).

Hwang, J.-Y., Myung, S.-T. & Sun, Y.-K. Chem. Soc.
Rev.
46, 3529–3614 (2017).

G. Ramos-Sanchez, I. Romero-Ibarra, J. Vazquez-Arenas, C. Tapia, N. Aguilar-Eseiza, I. Gonzalez,.
Solid State Ionics
303, 89–96 (2017).

Figure 1
Room-Temperature Nonaqueous Polyvalent Metal - Sulfur Batteries
Authors: Yu Xingwen , Manthiram Arumugam 
Published: February 2020

Electrochemical energy storage with a room-temperature lithium-sulfur (Li-S) chemistry is gaining overwhelming attention as a promising next-generation rechargeable battery technology for a broad range of applications.1 Beyond Li, sulfur batteries with other anode chemistries, such as sodium, potassium, magnesium, calcium, and aluminum are recently receiving considerable attraction as well.2 In comparison to lithium anode, Ca, Mg, and Al particularly offer multiple advantageous features in terms of safety, materials cost, and abundance. Therefore, rechargeable battery systems with Mg-S, Ca-S, and Al-S chemistries are promising low-cost options for the development of safe, large-scale electrical energy storage technologies. However, the research on these battery chemistries/technologies is still in its infancy and is currently hampered by many critical challenges.
Based on our research into the Li-S, Na-S, K-S, Mg-S, Ca-S, and Al-S batteries,3-8 this presentation will first compare the similarities and differences between the above six battery chemistries. Then, key efforts and significant endeavors toward the success in operating the Mg-S, Ca-S, and Al-S batteries will be particularly presented. Electrolytes play the most important role toward the reversible operation of these polyvalent metal – sulfur batteries. Next, multiple strategies to enhance the cycling performances of Mg-S, Ca-S, and Al-S batteries will be discussed. Specially, advanced cathode matrix materials and unique cathode structures will be detailed in this presentation. Finally, the critical challenges and future research and development directions for developing polyvalent metal – sulfur batteries will be prospected.

References

A. Manthiram, Y. Z. Fu, S. H. Chung, C. X. Zu and Y. S. Su, Chem Rev, 2014, 114, 11751-11787.

X. W. Yu and A. Manthiram, Small Methods, 2017, 1, 1700217.

A. Manthiram and X. W. Yu, Small, 2015, 11, 2108-2114.

X. W. Yu and A. Manthiram, Energy Storage Mater, 2018, 15, 368-373.

X. W. Yu and A. Manthiram, Acs Energy Letters, 2016, 1, 431-437.

X. Yu and A. Manthiram, Chem-Us, 2018, 4, 1200-1202.

X. Y. A. Manthiram, Adv Energy Mater, 2017, 7, 1700561.

X. W. Yu, M. J. Boyer, G. S. Hwang and A. Manthiram, Chem-Us, 2018, 4, 586-598.
Improving the Performance of All-Solid-State Microbatteries By Conformal Electrodeposition of Polymer Electrolyte into Self-Organized TiO2 Nanotubes
Authors: Sugiawati Vinsensia Ade , Vacandio Florence , Djenizian Thierry 
Published: February 2020

To date, microbatteries are in demand as small power sources to satisfy the market requirements with fast development of microelectronic devices. As more energy is required, a shift to all-solid-state 3D architectures has been proposed as a promising approach to tackle the challenge and achieve both high energy and power densities [1]. Hence, various types of microbatteries have been developed and are under investigation. It has been reported that self-organized TiO2 nanotubes (TiO2nts) can be utilized as anode material for Li-ion microbatteries [2]. The improved electrochemical performance of TiO2nts electrode has been mainly attributed to the larger surface area offered by 3D nanoarchitectured electrodes which is responsible for high reversible capacity, excellent rate capability and long cycle life [3]. To fabricate an all-solid-state Li-ion microbatteries, conventional liquid electrolytes need to be replaced by the solid electrolytes such as polymer electrolyte. We have reported that the electrodeposition of the polymer electrolyte into TiO2nts electrodes through cyclic voltammetry technique leads to the filling of the nanotubes by the thin polymer film [3].
In this work, we report the influence of the conformal electrodeposition on the full microbattery utilizing TiO2nts as anode, LiFePO4 as cathode and a drop-casted layer of methyl ether methacrylate-polyethylene glycol (MA-PEG) acting as electrolyte and separator. Clearly, the polymer-coated TiO2nts vs. LiFePO4 microbattery reaches higher capacity of ~98 mA h g-1 (~48 μAh cm-2 μm-1) compared to the bare TiO2nts vs. LiFePO4 microbattery (~12.5 mA h g-1 , ~6 μAh cm-2 μm-1) over 100 charge-discharge cycles. Galvanostatic charge-discharge profiles revealed the positive influence of electrochemical deposition of the polymer electrolyte into self-organized TiO2nts, as shown in Figure 1(a) and (b). In this communication, we will discuss the fabrication and characterization of all-solid-state microbatteries, as well as the influence of polymer-coated TiO2nts on their electrochemical performance.

References

[1] S. Ferrari, M. Loveridge, S.D. Beattie, M.Jahn, R.J. Dashwood, R. Bhagat, Latest advances in the manufacturing of 3D rechargeable lithium microbatteries, J. Power Sources. 2015, 28, 25-46.
[2] G.F. Ortiz, I. Hanzu, T. Djenizian, P. Lavela, J.L. Tirado and P. Knauth. Alternative Li-Ion Battery Electrode Based on Self-Organized Titania Nanotubes, Chem. Mater. 2009, 21 (1), pp 63–67.
[3] N. Plylahan, M. Letiche, M.K. Samy Barr, B. Ellis, S. Maria, T.N.T. Phan, E. Bloch, P. Knauth, T. Djenizian, High energy and power density TiO2 nanotube electrodes for single and complete lithium-ion batteries, J. Power Sources. 2015, 273, 1182–1188
[4] N. Plylahan, M. Letiche, M. K. S. Barr, T. Djenizian, All-solid-state lithium-ion batteries based on self-supported titania nanotubes, Electrochem. Commun. 2014, 4, 1388-2481.

Figure 1
Structure Engineering and Structure-Property Study of TiNb2O7 Nanofibers As Anode for Safer Lithium Ion Batteries
Authors: Ardoin Sydney , LaCoste Jed , Guo Hui , He Zizhou , Fei Ling 
Published: February 2020

Lithium ion batteries (LIBs) have been the dominant energy storage technology for a wide range of applications including portable electronic, electrical vehicles, and grid-scale energy storage. Recently with safety and performance in mind, TiNb2O7 (TNO) has been studied as a promising anode material. It offers a theoretical capacity of 387.6 mA h g-1, which is comparable to that of graphite (372 mA h g-1) and two times that of Li4Ti5O12 (175 mA h g-1). TNO also exhibits an operational voltage larger than 1.0 V (vs Li+/Li0), which helps to avoid formation of dendritic lithium and ensure safe operation. TNO with various morphology and size has been studied intensely since its discovery by Goodenough et. al. in 2011 including mesoporous microspheres, solid or porous nanoparticles, and solid or hollow 1D fibers. However, no comprehensive study which studies the structure-property-aspect of TNO has been completed.
Here, we are trying to prepare TNO with various morphology, size, and porosity as well as to study the correlation of TNO properties with electrochemical performance. Electrospinning technology is used to synthesize target materials, which are formulated from using poly(lactic acid) as a carrier polymer in various solvents (dimethylformamide, acetone, and dichloromethane) and adding titanium and niobium precursors. Parameters that affect the morphology of spun fibers are concentration, flow rate, applied voltage, collector plate distance, viscosity, and surface tension. Those parameters, especially solution chemistry, are carefully tuned to control the resulting fiber morphology and other properties. For example, solid, hollow, and porous (surface porous, inner porous, or highly porous) TNO fibers can be obtained by careful solvent selection as solvents have been proven to strongly affect evaporation and phase separation processes. All prepared TNO are further tested as anode materials in lithium ion battery and the property-performance correlation is carefully analyzed.
Improving Rate Capability and Coulombic Efficiency Via Crosslinking Sulfonated Chitosan Protective Coating on Natural Graphite Anode in Lithium Ion Batteries
Authors: Lu Chia-Yang , Chao Chi-Yang , Wu Nae-Lih 
Published: February 2020

Graphite is the mostly used anode material for commercial lithium-ion batteries (LIBs) because of several advantages including low operating potential and low cost. However, the formation of thick solid-electrode interphase (SEI) passivating layer due to solvent and electrolyte decomposition at the graphite surface would be harmful to both Coulombic efficiency (CE) and cell performance at high C-rate. In this work, we successfully develop a multifunctional polymeric artificial SEI (A-SEI) protective layer with thickness in nanometers on active natural graphite (NG) particles in the anode to concurrently promote the rate capability and the CE of the lithium-ion batteries.
The protective layer is composed of crosslinking sulfonated chitosan (X-SCS) containing sulfonated chitosan (SCS) with high degree of sulfonation as main polymer matrix and glutaraldehyde (GA) as the crosslinker. Different ratio of SCS and GA and a variety of curing conditions are applied to optimize the performance. The existence of sulfonic acid groups in X-SCS should allow lithium ions to be feasibly transferred between the electrolytes and the graphite as the pristine X-SCS membrane showed a good ion conductivity > 10-4 S cm-1 at room temperature upon only ~ 20 wt% liquid electrolyte uptake. X-SCS layer should also provide sufficient mechanical strength to protect graphite from exfoliation as a high than 1 GPa Young’s modulus was observed for the pristine X-SCS membrane. The complete coverage of X-SCS on NG was confirmed by testing the battery employing liquid electrolyte (LE) containing 40 wt% PC, which would cause serious exfoliation of NG and lead to unusual high discharge capacity and low CE in the first lithiation process. Normal discharge curves and a much improved CE are observed for X-SCS coated NG in addition to stable cycling performance up to 40 cycles, suggesting the coverage of X-SCS is complete and stable to effectively prevent the direct contact of LE with NG. X-SCS coated NG provided the corresponding half cell an average CE over 99.5% and capacity > 99.5% when operating at 0.3C and room temperature for 100 cycles. In contrary, the average CE for un-coated NG was only 98.7%. Using the charging (de-lithiation) capacity at 0.1 C as reference, an over 98% capacity retention was observed for X-SCS coated NG cell at 5 C while the capacity retention of the bare NG cell was only 90%.