bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optical Studies of Reactively Co-Sputtered Bcn Thin Films
Authors: Prakash Adithya , Sundaram Kalpathy B 
Published: February 2020

The motivation behind the boron carbon nitride (BCN) ternary compounds is their similarities in the structure and difference in properties between graphite and hexagonal boron nitride (h-BN). Both theoretical calculations and experimental studies show that BCN compounds exhibit excellent mechanical, optical and electrical properties [1], [2]. In particular, the possibility to control the band gap (EG
) by atomic composition and structure makes them good candidates for the application in electronic and photonic devices [3], [4].
The optical characteristic like transmittance is improved with initial incorporation of nitrogen into the film composition and has a stable trend with further increase in nitrogen concentration. Also the optical band gap of BCN (2.2eV-3eV) increased with incorporation of nitrogen and said to follow a linear trend between B4C (2eV) and BN (4eV) [5]. The co-sputtering helps in creation of films with graded indexes of refraction as well. It gives more freedom to vary the composition as when compared to single target sputtering. Thickness uniformity and the film quality are better when using co-sputtering.
Dual target approach will be conducted to prepare BCN tin films. In this work we are depositing BCN thin films on quartz substrates using two targets namely B4C and BN using RF power and DC power respectively at different N2/Ar gas flow ratios. Also the input power for B4C and BN are varied to achieve different composition of the BCN thin films to control the optical properties. The optical properties like transmission and reflectance are studied using the UV-visible spectrophotometer. The optical absorption is studied by Tauc plot which is instrumental in finding the optical band gap of the material and the refractive index.
REFERENCES
[1] I. Caretti, J.M. Albella, I. Jiménez, Diamond Relat. Mater., 16 (2007), p. 1445
[2] A. Perrone, A.P. Caricato, A. Luches, M. Dinescu, C. Ghica, V. Sandu, A.Andrei , Appl. Surf. Sci., 133 (1998), p. 239
[3] M.O. Watanabe, S. Itoh, K. Mizushima, T. Sasaki, J. Appl. Phys., 78 (1995), p. 2880
[4] P.R. Fitzpatrick, J.G. Ekerdt, J. Vac, Sci. Technol. A, 26 (2008), p. 1397
[5] Optical characterization of BCN films deposited at various N2/Ar gas flow ratios by RF magnetron sputtering
.
Investigation of Electroless-Electrolytic Ni-Mo Binder-Free Electrode for Ultracapacitor Applications
Authors: Stephens Jamal Frederon , Kalu Egwu Eric , Gomez Jamie , Weatherspoon Mark H , Zheng Jim P 
Published: February 2020

This paper provides results of a thin film binder-free Ni-Mo electrode ultracapacitor that was fabricated by using electroless-electrolytic (EE) technique with a glass fiber separator and 0.5M Na2SO4electrolyte solution.
Galvanic cycles were performed to characterize the charge/discharge curves of the Ni-Mo ultracapacitor at different currents as shown in figures 1 & 2. The capacitance was then analyzed by using equation (1).
where C is the capacitance normalized by the geometric area of the electrode, I is the current set to the cell and Ais the geometric area.
Figure 3 illustrates the capacitance relationship between 0.1 and 0.5 mA. From the plot it seems that at 0.1 mA the capacitance is more consistent and larger than at 0.5 mA. This can be because looking at the galvanic cycles for 0.5 mA we see a bend in the curve which can occur from the internal resistance being large. [1]

We will explore options and approaches to smoothing the curves to not only get a better capacitance values but obtained more consistent capacitance over different current rates.
References

Steven Risser, Elvin Beach, Megan Moore and Olga Koper, “Application of Metal Oxide Supercapacitor for Naval Applications”, ASNE Proceedings (2012)
Characterization of Reaction Products on the Surface of Li/Air Battery Electrodes
Authors: Lee Chan Kyu , Park Yong Joon 
Published: February 2020

Recently, the Li/air batteries have received a lot of attention as an alternative of lithium ion batteries (LIB), since they provide higher energy density than LIB. The Li/air batteries are composed of air electrode, separator, electrolyte, and anode electrode. Among them air electrode plays a key role because the capacity and cycle life of the Li/air batteries are highly dependent on the air electrode. Therefore many studies have focused on the development of air electrode with enhanced electrochemical performances. During the discharge, lithium ions and oxygen dissolved in electrolyte have a reaction on the surface of air electrode and forms reaction products like Li2O2. Interestingly, it has been reported that the morphology of the reaction products can affect the electrochemical property of the Li/air cell such as cyclic performance and overpotential [1, 2]. Our study gives importance to characterize the morphology of reaction products. To achieve the image of morphologies on the surface of air electrode, we have composed the air electrode on the nickel grid for TEM and manufactured cell. After test of cell using the grid, we could take the TEM images of reaction products. In addition, it is observed that morphologies have difference according to several conditions like the presence of a catalyst or the rate of discharge/charge. It is expected that observation of morphologies in our approach could signpost for development of enhanced air electrode for Li/air batteries.
Reference
[1] Y. Shao-Horn, B. M. Gallant, R. R. Mitchell, D. G. Kwabi, J. Zhou, L.Zuin, C. V. Thompson, J.Phys. Chem. C 2012, 116, 20800-20805
[2] Y. shao-Horn, B. M. Gallant, D. G. Kwabi, R. R. Mitchell, J. Zhou, C. V. Thompson, Energy Environ. Sci. DOI: 10.1039/c3ee40998h
Doped Carbonate Alkaline Battery Cathodes
Authors: Hertzberg Benjamin Joseph , Sviridov Lev , Stach Eric A. , Mehra Aashna , Steingart Daniel A. 
Published: February 2020

There is a need for reliable, low-cost energy storage for electric vehicle applications. While advanced Li-ion batteries may possess sufficient power and energy density to be useful for electric vehicles, their high manufacturing and materials costs make them unsuitable outside of a relatively small market niche. Alkaline batteries, one of the most common modern forms of primary battery, are potentially ideal for electric vehicles. These cells depend on a reaction between zinc (Zn) and manganese dioxide (MnO2) to generate energy. This reaction gives alkaline batteries a relatively high energy density and a low cost per kilowatt-hour, but phase transformations occurring during deep discharge prevent recharge. In a typical alkaline battery, useful rechargeability with minimal capacity losses can only be achieved if no more than 10% of the cells capacity is used. [1]
We have developed a new family of electrode materials, new to the literature, which consist of aragonite- or calcite-type carbonates with extensive substitution of manganese atoms on carbon sites. These materials are produced by a simple one-step hydrothermal process, which transforms the surface of a carbon precursor material into an manganese-doped carbonate. Permanganate salts used in the synthesis process result in extensive substitution of manganese atoms into the crystal structure without significant changes in long-range order. These materials have superior capacity, rate capability and cyclability compared to gamma MnO2, with comparable cost. In this presentation, we will describe these materials as we have characterized them via electroanalytical, X-ray and electron microscopy techniques.
References:
1. Shen, Yuwei, and Karl Kordesch. "The mechanism of capacity fade of rechargeable alkaline manganese dioxide zinc cells." Journal of power sources 87.1 (2000): 162-166
Acknowledgements:
This work was performed with financial support from the National Science Foundation CMMI 1402872, Department of Energy ARPA-E RANGE DE-AR0000400, and the Laboratory Directed Research and Development Program of Brookhaven National Laboratory (LDRD-BNL) under Contract No. DE-AC02-98CH 10866 with the U.S. Department of Energy. Use of the National Synchrotron Light Source, Brookhaven National Laboratory, was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-98CH10886.
Image Captions:
Fig. 1: Structure of manganese-doped barium carbonate (witherite). Barium is represented as green, oxygen as red, manganese as magenta, and carbon as black.
Stability Investigation of Inorganic Li Conductors As Protective Layers for Li-Air Batteries
Authors: Fung Kuan-Zong , Ni Chung-Ta , Tsai Shu-Yi , Chen Mei-Han 
Published: February 2020

The development of Li-air battery has received great attention recently. However, using metallic lithium directly as an anode has been challenging due to the high reactivity of Li. Protective coatings with ionic conduction on metallic Li has be proposed to overcome this problem.Inorganic Li ion conductors may be suitable for being used as the protection layer.
NASCION-type LiTi2(PO4)3 and perovsikte-La0.50Li0.50TiO3 are known to be inorganic solid electrolytes with adequate conductivity in a range of 10-3 S/cm after required modification. However, Li tends to react with La0.56Li0.33TiO3 due to the incorporation of the released electrons with Ti+4 ions. Simultaneously, Li+ ions will migrate into the vacant sites in the cation sublattice. As a result, La0.50Li0.50TiO3 perovsikte becomes a mixed ionic/electronic conductor after reacting with Li. On the other hand, limited reaction was observed on the Li1+xAlxTi2-x(PO4)3 electrolyte when the metallic Li was used as the anode.
In order to improve the stability of Li1+xAlxTi2-x (PO4)3, a concept of composite electrolyte based on NASCION-type LiTi2(PO4)3 and perovsikte-La0.50Li0.50TiO3 is proposed. With proper mixing and distribution of these two electrolytes, a better stability from the composite electrolyte is expected.
Thus, the objective of this work is (1) to develop a composite electrolyte based on the mixture of Li1+xAlxTi2-x (PO4)3, and La0.50Li0.50TiO3, (2) to analyze the interface reaction between two components of composite cathode, (3) to investigate the electrical conduction/stability of composite as a function of volume fraction, grain size, and thickness, (4) to evaluate the feasibility of using composite electrolyte for Li-Air battery. The stability of composite electrolyte will be determined based on the measurement of the induced electronic conductivity and the open circuit voltage after a Li-air cell is assembled.
NaCrO2-Based Batteries: Effects of Processing
Authors: Sawicki Monica , Shaw Leon 
Published: February 2020

Na-ion batteries (NIBs) have attracted substantial attention lately as an alternative electrochemical energy storage technology. In this study, we report the effects of processing conditions on the electrochemical properties of Na-ion batteries made of the NaCrO2 cathode. NaCrO2 is synthesized via solid state reactions. The as-synthesized powder is then subjected to high-energy ball milling under different conditions. The CR2032 coin cells made using the as-synthesized NaCrO2 powder exhibit a specific capacity of 110 mAh/g in the first discharge at 0.3C rate. The specific capacity decreases gradually in the subsequent charge/discharge cycles. The observed electrochemical properties are similar to those reported previously [1,2].
High-energy ball milling has reduced the particle size drastically. However, after subjecting to high-energy ball milling the specific capacity for NaCrO2 degrades significantly. X-ray diffraction reveals that the lattice distortion has taken place during high-energy ball milling, likely forcing some Cr ions into the tetrahedral site and thus blocking the pathway for Na intercalation and de-intercalation. This study shows that a balance between reducing the particle size and maintaining the layered structure is essential to obtain high specific capacity for the NaCrO2 cathode.
References:

S. Komaba, C. Takei, T. Nakayama, A. Ogata and N. Yabuuchi, “Electrochemical intercalation activity of layered NaCrO2 vs. LiCrO2,” Electrochem. Commun., 12, 355-358 (2010).

S. Komaba, T. Nakayama, A. Ogata, T. Shimizu, C. Takei, S. Takada, A. Hokura and I. Nakai, “Electrochemically reversible sodium intercalation of layered NaNi0.5Mn0.5O2 and NaCrO2,” ECS Transactions, 16, 42, 43-55 (2009).
A New Approach to the Lithium-Oxygen Cell Via the Utilisation of Redox Shuttles
Authors: Frith James T , Garcia-Araez Nuria , Owen John R. 
Published: February 2020

Lithium-O2 cells, with a theoretical specific energy of around 5 times higher than lithium-ion cells have the potential to become the technology powering tomorrow’s electric vehicles. However, since they were first reported by Abraham and Jiang[1] they have faced problems and setbacks. The principal problem was of instability of organic non-aqueous electrolytes to the superoxide ion formed as an intermediate discharge product [2]. Ionic liquids are a promising alternative to traditional carbonate based electrolytes, and indeed recent works have shown that Pyr14TFSI is relatively stable to superoxide [3–5]. Having identified a stable electrolyte we have then looked at the problem of electrode passivation by the insoluble and insulating discharge product lithium peroxide [6], which produces a significant reduction on the practical capacity.
This work continues our previous study on the use of ethylviologen triflate as a mediator/redox shuttle for the discharge reaction [7], with a study of mediator action by the shuttle molecule to achieve a 2-electron reduction of oxygen to form lithium peroxide away from the electrode surface. This eliminates electrode passivation as shown in Fig. 1. We will also present an in-depth study into the mechanism of oxygen reduction by ethylviologen triflate and other candidate mediators.
The need for mediators for the charge reaction has also been stated by Bruce et
al.,[8] who found TTF to be a redox mediator in DMSO. Our own studies of TTF have found it to be unsuitable for use in in Pyr14TFSI due to its lower oxidation potential, so we have focused on the use of other compounds to carry electrons back to the electrode while the charge reaction converts the lithium peroxide back to oxygen.
[1] K.M. Abraham, Z. Jiang, J. Electrochem. Soc.143 (1996) 1–5.
[2] F. Mizuno, S. Nakanishi, Y. Kotani, S. Yokoishi, H. Iba, Electrochemistry. 78 (2010) 403–405.
[3] J.T. Frith, N. Garcia-araez, A.E. Russell, J.R. Owen, Prep.(n.d.).
[4] I.M. AlNashef, M. a. Hashim, F.S. Mjalli, M.Q.A. Ali, M. Hayyan, Tetrahedron Lett.51 (2010) 1976–1978.
[5] S. Randström, G.B. Appetecchi, C. Lagergren, A. Moreno, S. Passerini, Electrochim. Acta. 53 (2007) 1837–1842.
[6] V. Viswanathan, K.S. Thygesen, J.S. Hummelshøj, J.K. Nørskov, G. Girishkumar, B.D. McCloskey, et al., J. Chem. Phys.135 (2011) 214704.
[7] M.J. Lacey, J.T. Frith, J.R. Owen, Electrochem. Commun.26 (2013) 74–76.
[8] Y. Chen, S.A. Freunberger, Z. Peng, O. Fontaine, P.G. Bruce, Nat. Chem. 5 (2013) 489–94.
Characterization of Polymerized Sulfur Cathodes upon Cycling
Authors: Schaefer Jennifer L. , Kim Jenny , Oleshko Vladimir P. , Char Kookheon , Pyun Jeffrey , Soles Christopher L. 
Published: February 2020

Rechargeable Li-S batteries offer an unprecedented opportunity for energy storage technology. Sulfur is a very cheap material with remarkably high energy storage density when used as a cathode. Sulfur cathodes have historically suffered from a myriad of problems, including low active material utilization due to low electronic conductivity and significant capacity fade upon cycling due to polysulfide dissolution and cracking of the cathode. The main approach for improving active material utilization and maintaining capacity has been to sequester sulfur within various forms of electronically conductive, nanostructured carbons.
Recently, researchers have developed a copolymer with a very high sulfur content via a process termed inverse vulcanization.1 The sulfur-containing polymer is inexpensive to produce, and full Li-S cells utilizing this copolymer in the cathode achieve capacities of 635 mAhr/g after 500 cycles at a rate of C/10.2

This talk will focus on results of characterization studies to determine the morphology and composition of the sulfur copolymer cathode and electrolyte solution during the cycling process. Microscopy studies show that the sulfur copolymer cathode maintains greater uniformity and shows less cracking upon cycling than an elemental sulfur cathode. We will also report on results of in-situ Raman and XPS studies to identify the products present in the cathode and in the electrolyte at various potentials during cycling.
1. J. Pyun et. al., Nature Chemistry, 5:518-524, 2013.
2. J. Pyun, et. al., ACS Macro Letters, 3:229-232, 2014.
Sn-Polyacrylate Composite Electrode for Advanced Na-Ion Batteries
Authors: Fukunishi Mika , Yabuuchi Naoaki , Kuze Satoru , Son Jin-Young , Cui Yi-Tao , Oji Hiroshi , Komaba Shinichi 
Published: February 2020

Na-ion batteries are attractive rechargeable batteries as Li-free batteries. Sodium resources are abundant, inexpensive elements and unlimited everywhere, unlike lithium availability. Additionally, relatively low redox potential of sodium is slightly higher, 0.3 V, than that of Li/Li+. Therefore, many researchers extensively study about Na-ion batteries nowadays and the electrode performance is significantly improved, which is being competitive for Li-ion batteries. We have demonstrated approximately 300 mAh/g discharge capacity after 50 cycles by using hard-carbon electrodes in Na cells.[1] In order to achieve higher energy battery, electrode materials with high reversible capacity is needed. Thus we have examined group 14 elements (C, Si, Ge, Sn, and Pb) as the potential negative electrodes materials for Na-ion batteries.[2] In our previous report, we demonstrated acceptable electrode performance with tin, approximately 500 mAh/g of reversible capacity after 30 cycles.[2] However, reversible capacity was lower than that of expected capacity (847 mAh/g based on the formation of Na15Sn4).[3]In this study, the factors affecting electrode performance of tin electrochemically alloying with Na are described; slurry conditions, cut-off voltages and so on. After the optimization of tin composite electrodes, finally, we have demonstrated more than 650 mAh/g of reversible capacity with good capacity retention.
Nanosized tin powder (<150 nm, Sigma-Aldrich Co., Ltd), graphite, and sodium polyacrylate (PANa) were mixed with 80:10:10 (wt%) to prepare slurry with deionized water mixed with or without methanol (5 vol%) and were cast onto Al foil to make composite electrodes. The electrode was tested in aprotic Na cell with NaPF6PC solution with FEC (2 vol%) additive. As shown in Fig.1, the higher reversible capacity (approximately 700 mAh/g) is obtained by addition of 5% methanol to the slurry. Approximately 200 mAh/g discharge capacity is increased compared with the slurry prepared without the addition of methanol. Change in the electrode morphology prepared with or without methanol in the slurry was observed by SEM (Fig. 2). SEM observation reveals that the uniform morphology and better dispersion of the active materials for the composite electrode prepared with methanol-added dispersant. It indicates that methanol additive is effective to improve the dispersion of tin and carbon materials in the aqueous slurry, resulting in better electrochemical properties in Na cells. Based upon these results, we will discuss the effects of cut-off voltages in relation to the changes in the surface of tin electrodes characterized by secondary ion mass spectroscopy and photoelectron spectroscopy in synchrotron facility.

References
:

[1] M. Dahbi, N. Yabuuchi, K. Kubota, K. Tokiwa, S. Komaba, submitted.
[2] S. Komaba et al., Electrochem. Commun., 21, 65 (2012).
[3] L. D. Ellis et al., J.

Electrochem.Soc., 159, A1801 (2012).
Advanced 3D Imaging and Analysis of SOFC Electrodes
Authors: Tariq Farid , Yufit Vladimir , Kishimoto Masashi , Cui Guansen , Somalu Mahendra , Brandon Nigel P. 
Published: February 2020

Meeting increasing energy demands, storage demands and energy portability in a clean efficient manner will be expedited through an ability to directly image solid oxide fuel cell (SOFC). Tomographic techniques allow for the 3D imaging and chracterisation of complex microstructures down towards tens of nanometers; which are inadequately described in 2D. The performance of the SOFCs is dependent on nano/micro-structure as the electrochemical reactions and transport phenomena are strongly affected by the complex porous microstructure, where important reactions occur. Furthermore, during processing or operation microstructural evolution may degrade electrochemical performance
Here we use tomographic techniques to probe the 3D electrode structure at micro-nanometer length scales. Subsequently, micro/nano structural changes are followed to facilitate understanding the differences which occur with shape, structures and morphology at high resolution. Additionally the quantification of electronic, ionic and gas interfaces are also correlated with observed differences in electrode behaviour. When coupled with electrochemical and thermo-mechanical computational models, the results show nano/microstructural and compositional variations can significantly affect performance of SOFC electrodes. Altogether this provides important insights for electrode design and understanding sources of performance degradation.
Effect of Heat Treatment on Thermal Sprayed Protective Oxides for SOFC Metallic Interconnects
Authors: Fung Kuan-Zong , Tsai Shu-Yi , Ni Chung-Ta , Ho Hsin-Chia 
Published: February 2020

For the stack design of solid oxide fuel cells (SOFC), metallic interconnects such as Crofer 22H is widely used to replace ceramic interconnects. Most metallic interconnects use chromium-containing alloy that form chromia scales to suppress further oxidation at high temperatures. Since chromia may react with cathode and cause degradation, a protective oxide may be used to suppress the growth of chromia. Although several techniques have been adopted to deposit oxides on metallic interconnects, the thermal spray is found to be an appropriate technique. Thermal spray coating process has been widely used to produce a high quality coating by a combination of high temperature, high energy heat source, a spraying gas medium, such as argon, and high particle velocities. This process allows the spraying of various types of metallic or ceramic coatings on to a wide range of substrate materials. As a result, uniform coating layer with excellent bond strength to substrate is obtained without noticeable distortion.
For metallic interconnects used for SOFC applications, several oxides such as LaMnO3 and LaCrO3-based perovskite oxides and (Mn,Co)3O4, (MCO), with spinel structure have been used to form protective layer for metallic interconnects. However, the temperature during thermal spraying may be high enough to change the crystal structure and conductivity of protective oxides. The heat treatment is believed to be an appropriate method to obtain adequate properties for protective oxide. Thus, the after-spray treatment will play an important role for metallic interconnects to obtain desired electrical properties. In this study, the high-temperature ferritic stainless steel Crofer 22H and nickel-chromium alloy Inconel 625 were first thermally sprayed with oxides with perovskite and spinel structures.
The objective of this work is to investigate the effect of after-spray treatment on the crystal structure and conductivity of the sprayed oxide. The crystal structure, morphology and electrical conduction of interconnect with sprayed oxide films will be examined by using XRD, FESEM and resistance measurement.