bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Stray Light Suppression Using Carbon Nanotube Based Black Coating
Authors: Wang Dan , Hall Timothy D , Radhakrishnan Rajeswaran , Inman Maria , Taylor E. J. , Skinn Brian , Snyder Stephen 
Published: February 2020

Space-borne instruments, such as exo-atmospheric optical sensors and seeker telescopes, require low reflectivity surfaces to minimize stray and reflected light across the visible and infrared wavebands. Black surface coating treatments have been demonstrated as effective approaches to obtain low reflective surfaces. The surface features and intrinsic properties of the coating materials play an important role for scattering, absorbing, or trapping light. The excellent optical absorption performance, light weight, and large surface areas of carbon nanotubes (CNTs) make them as ideal coating materials for obtaining low reflectivity surfaces.
Within this context, Faraday Technology Inc. is developing an electrophoretic deposition process to deposit dense, multi-walled carbon nanotubes onto test substrates. Specifically, we are evaluating the effect of bath formulation and pulsed electric field deposition parameters then characterizing the deposited CNT coatings by reflectance spectra. The bath formulation was controlled by modifying the surface charge of the carbon nanotubes by polymer dispersants or bound functional groups, next these functionalized materials were electrophoretically deposited onto the substrates under an applied pulsed electric field. As shown in Figure 1, it is possible to achieve a uniform CNT coating on a stainless steel substrate (Figure 1 Inset) that achieves a diffuse reflectance of 0.8% ~ 1.2% over the visible range. Currently, we are working to optimize the pulsed electric field conditions to achieve lower reflectivity CNT coating formation.
If successful this program will demonstrate a scalable technique for producing CNT black coatings can not only be used for minimizing stray and reflected light for space-borne instruments, but also offer potential applications in other optical related devices which request low reflective surfaces, such as solar cells.

Acknowledgements: The financial support of NASA Contract No. 80NNSC18P2062 is acknowledged.

Figure 1
Development of a New Copper Corrosion Screening Methodology for Application in Microelectronics
Authors: Alptekin John , Salunke Ashish Shivaji , Asokan Muthappan , Issac Goutham , Caperton Joshua , Chyan Oliver 
Published: February 2020

Due to the constant miniaturization of microelectronics, the aim of the semiconductor industry has been to increase the packaging density of devices. Wire bonds form the primary interconnects between the integrated circuit chip and the metal lead frame in semiconductor packaging. Gold (Au) wire has been used for wire bonding in the electronics industry because of its mechanical and electrical properties, high reliability, and ease of assembly. However, due to the increasingly high cost of Au, alternative wire bonding materials have been considered. Copper (Cu) is gradually replacing Au because it exhibits not only a high resistance to electromigration, but also has excellent electrical conductivity and a low resistivity. The benefit of copper’s conductivity is that it reduces heat generated by joule heating, thus reducing RC delay. However, copper also has its drawbacks; tiny amounts of contaminant can corrode Cu interconnects, leading to the failure of entire microelectronic devices. On-chip corrosion within Cu interconnect microstructures can result in increased defectiveness, which causes serious reliability issues and decreases production yield. Copper is susceptible to corrode in acidic and strong alkaline solutions in the presence of oxygen and other oxidants. Effective corrosion monitoring is critical as an early alert before the onset of corrosion-related failure.
In this study, we report a new method for monitoring the corrosion of copper relevant to the microelectronics industry through the combination of electrical resistance measurement changes of Cu wire and microscopic time-lapse imaging. Industry-grade 99.99% Cu bonding wire (diameter = 25μm) was exposed to the harsh, oxidizing conditions of ammonium persulfate, and its change in resistance was monitored. As the corrosion of Cu bonding wire took place, the cross-sectional area of the wire decreased, causing an increase in its resistance (via R= ρ•l/A). During the resistance monitoring, the simultaneous microscope time-lapse imaging enabled Cu corrosion to be observed in real time. Due to the combined quantitative and qualitative nature of this metrology, it provides detail on the corrosion process that might not be obtained by traditional corrosion tests. While ammonium persulfate will almost never be encountered by an IC device during normal use, it provides a rapid screening environment that can quickly distinguish between corrosion inhibition and no protection at all. This metrology was used to test both bare Cu bonding wire and corrosion-inhibitor coated bonding wire, and showed a drastic difference in their corrosion rate and behavior. This work ultimately aids with inhibitor selection and inhibitor coating design that will help ensure long term reliability of electronics used in industrial applications.

Figure 1
Dynamical Measurements of Surface Transformations By Galvanic Replacement Reactions on Metal Electrode Interfaces
Authors: Schichtl Zebulon , Mehrabi Hamed , Coridan Robert 
Published: February 2020

There are a number of possible structural and compositional outcomes for galvanic replacement reactions of noble metal ions on transition metal substrates. Some
combinations nucleate separate layers and eventually cover an entire electrode, while others form complex alloy phases. The chemical mechanism of galvanic replacement is well studied but little is known about the resulting solid-state transformations. Here, we use in situ electrochemical methods to monitor the energetics of galvanic replacement reactions at metal electrode interfaces. We show that open circuit potential and cyclic voltammetry measurements can be used to follow the progress of the reactions and rates of cathodic and anodic half reactions. Tracking the dynamics of the open circuit potential over time allows us to observe the effects galvanic replacement has on the electrode/electrolyte interface, and through cyclic voltammetry, we are able to investigate reaction kinetics of template metal dissolution and metal deposition at any point during the replacement process. Finally, we will discuss how these monitoring strategies can be useful for fabricating hierarchically structured surfaces for selective electrocatalytic reactions.
Fibrous Organosulfur Compounds As Cathode Materials for High-Performance Lithium-Sulfur Batteries
Authors: Weret Misganaw Adigo , Hwang Bing-Joe , Jeffrey Kuo Chung-Feng , Su Wei-Nien 
Published: February 2020

Rechargeable lithium-sulfur (Li-S) batteries consist of lithium metal having high theoretical specific capacity (3860 mAh g-1) as an anode [1] and sulfur with a theoretical capacity (1672 mAh g-1) as a cathode [2] are considered as the most promising candidates for next generation energy storage technologies. Organosulfur compound cathode materials deliver high specific capacity, have low cost, suppress the polysulfide dissolution and decipher issues related to shuttling effect. Though, these cathode materials have promising advantages, inherent problems such as low sulfur loading and poor rate capability hinder practical applications.
Here, we prepare a fibrous organosulfur compounds using an electrospinning method followed by the heat treatment. The nanofiber organosulfur compounds prepared have a high surface area, high porosity, and a unique nanonetwork structure which are important for high electrochemical performance Li-S batteries. As a result, the prepared nanofiber organosulfur compounds offer high lithium storage capacity >1000 mAh g-1 with stable cycle life over 100 cycles at 0.1C, high rate capability, and hold high active material contents (52 wt%).
Current-Dependent Growth Mechanisms of Sodium Metal Anode in Diglyme-Based Electrolytes
Authors: Ma Bingyuan , Bai Peng 
Published: February 2020

Sodium-ion batteries are economical substitute for lithium-ion batteries due to the earth abundance of sodium element [1, 2]. Similar to lithium metal anodes, while sodium metal anodes hold the promise to improve the energy density of next-generation sodium-ion batteries, the nonuniform electrodeposition of sodium metal that can lead to internal shorts remains a major obstacle toward its practical applications [3]. Here, we systematically investigated the electrodeposition of sodium in diglyme-based electrolytes in our unique capillary cells and realistic split cells. While a similar transition of electrodeposition mode to dendritic growth at Sand’s time was observed for sodium [4], only the smooth surface growths were observed at under-limiting current densities, suggesting a possible much higher cycling efficiency due to much less surface areas to be covered by the solid electrolyte interphase (SEI) layers. By examining the limiting current and Sand’s time obtained from operando experiments with the capillary cells, the diffusion coefficient (1.13×10-6 cm2 s-1) and transference number (0.45) of sodium ions in 1M NaClO4 in diglyme were accurately extracted, which were further verified by post-mortem analyses of linear sweep voltammetry experiments with split cells. The unique two current plateaus, shown in Figure 1, surprisingly can be explained by a single limiting current density in a self-consistent manner. At such plateaus, deposits of sodium metal were discovered to grow along the surface, rather than through the pores, of the ceramic-coated separator and form equiaxed and columnar dendrites with orthogonal branches similar to that found in solidification [5].Our work provides a platform to not only evaluate the current-dependent growth mechanisms of sodium, but also reveal the roles of separators toward designing safe sodium metal batteries.

References

[1] D. Larcher and J. M. Tarascon. Towards greener and more sustainable batteries for electrical energy storage. Nature Chemistry. 2015; 7(1): 19-29.
[2] M. D. Slater, D. Kim, E. Lee and C. S. Johnson. Sodium-Ion Batteries. Advanced Functional Materials. 2013; 23(8): 947-958.
[3] C. L. Zhao, Y. X. Lu, J. M. Yue, D. Pan, Y. R. Qi, Y. S. Hu, et al. Advanced Na metal anodes. Journal of Energy Chemistry. 2018; 27(6): 1584-1596.
[4] P. Bai, J. Li, F. R. Brushett and M. Z. Bazant. Transition of lithium growth mechanisms in liquid electrolytes. Energy & Environmental Science. 2016; 9(10): 3221-3229.
[5] L. Granasy, L. Ratkai, A. Szallas, B. Korbuly, G. I. Toth, L. Kornyei, et al. Phase-Field Modeling of Polycrystalline Solidification: From Needle Crystals to Spherulites-A Review. Metallurgical and Materials Transactions a-Physical Metallurgy and Materials Science. 2014; 45A(4): 1694-1719.

Figure 1 Linear sweep voltammetry curve of the sodium symmetric split cell with twelve layers of ceramic coated separators with the ex-situ photos at different stages of the electrodeposition.

Figure 1
Hybrid Polymer Electrolytes for Lithium Metal Batteries
Authors: Wu Haiping , Liu Bin , Li Qiuyan , Zhang Linchao , Zhang Ji-Guang , Xu Wu 
Published: February 2020

The use of lithium (Li) metal as anode in rechargeable batteries has been revived recently because Li metal has the potential to double the specific energy density of the state-of-the-art Li ion batteries. However, Li dendrite growth and low Coulombic efficiency still hinder the application of Li metal batteries. The urgent and most important thing is to develop an electrolyte which can enable Li metal to be used as anode with high safety and good stability. Solid polymer electrolytes (SPEs) have attracted much attention due to their outstanding advantages over conventional liquid electrolytes, including no leakage of electrolytes, good flexibility, low flammability, high safety and stable contact with the electrodes. As the most widely studied polymer in SPEs, polyethylene oxide (PEO) still faces some challenges, including the low ionic conductivity (σ < 10-5 S cm-1) at room temperature (RT) and instability when charged to above 4 V vs. Li/Li+.
In this work, we developed a hybrid polymer electrolyte (HPE) which exhibits high oxidation voltage and high ionic conductivity. The HPE shows an oxidation stability above 4.5 V vs. Li/Li+ when platinum was used as the working electrode in a three-electrode cell. The pure HPE has an ionic conductivity of 0.46 mS cm-1 and 2.8 mS cm-1 at 30 °C and 60 °C, respectively. The increased electrochemical window and the high conductivity of the HPE enable the Li||LiNi1/3Mn1/3Co1/3O2 cells (with an areal capacity loading of 2 mAh cm-2) to show a stable cycling in the voltage range of 3.0 – 4.2 V, having a high capacity retention of 84.2% after 170 cycles under charge rate of C/5 and discharge rate of C/3 at 60 °C. More details will be reported during the presentation at the meeting.

Acknowledgement

This work was supported by the Assistant Secretary for Energy Efficiency and Renewable Energy, Office of Vehicle Technologies, the Advanced Battery Materials Research (BMR) Program of the U.S. Department of Energy (DOE) under contract no. DE-AC02-05CH11231.
Dual-Crosslinked Polyacrylamide Binders with Various Polysaccharides and Their Application to High Capacity Anodes
Authors: Gendensuren Bolormaa , Kim Jinyoung , Oh Eun-Suok 
Published: February 2020

Over the last 20 years, much attention has been devoted to developing new electrode materials with high energy and power densities for lithium ion batteries (LIBs). However, a binder material providing an integrity in a composite electrode seems to have an attention recently due to its great influence on the long-term cyclic stability, rate capability, and irreversible capacity loss of the electrodes. High capacity anodes experiencing large volume change such as silicon is strongly dependent on proper choice of polymeric binder. Polyvinyledene difluoride (PVdF) is the most common binder in commercial LIBs. However, the Si electrode fabricated with PVdF binder showed rapid capacity fades for the first tens of cycles caused by the poor adhesion strength of PVdF on current collector. Moreover, it dissolves only in toxic and expensive organic solvent, m-methyl-2-pyrrolidone, leading to environmental issues for the electrode manufacturing process.
To replace the organic solvent, environmental-friendly water soluble polymers such as, polyacrylic acid (PAA), polyvinyl alcohol (PVA), carboxymethyl cellulose, and sodium-alginate (SA) began to be applied to high capacity Si-based anodes and showed excellent binder performance, when compared to conventional PVdF binder due to their robust adhesion to active material and current collector and low electrolyte swelling to maintain the mechanical properties of binder. In spite of these endeavors, further improvement in the binder materials is still required, especially for the use high capacity anodes to have sufficiently stable cyclic performance for commercial application.
In this presentation, water-treated dual-crosslinked binder systems will be introduced for a high capacity silicon/graphite electrode. A polysaccharide is first grafted with polyacrylamide (PAAm), and ionic and chemical crosslinkings are subsequently performed to complete dual-crosslinking in the grafted polymer. Three types of polysaccharides, sodium-alginate, sodium-carboxymethyl cellulose, and pectin, will be employed and compared for their performance as a binder material for high-capacity anodes. A variety of characterization tools will used to examine the electrochemical performance of the electrodes containing the dual-crosslinking binder systems.
Solid-State Li-O2 Battery Using a Perovskite Type Solid Electrolyte with an Improved Interfacial Property
Authors: Khan Tamal T. , Park Chan-Jin 
Published: February 2020

Theoretically Li–O2 batteries can release an energy density of 11 680 W h kg-1 comparable to that of gasoline (13 000 W h kg-1) by integrating the metal lithium with readily available ambient oxygen as an active material for cathode. Even based on the entire battery system, the capacity of ~1000 W h kg-1 is still several times higher than that of Li-ion batteries. Thus, Li–O2 batteries have attracted significant attention as a possible green alternative to current lithium-ion batteries for electric vehicles. Though Li-O2 batteries have promising performance, several issues still exist in its practical operation. One major issue is the use of liquid electrolytes, which causes several problems including evaporation, leakage, flammability, low oxygen solubility and diffusion, and chemical and/or electrochemical instabilities. The use of a solid-state electrolyte can be alleviated this issue. In addition, the solid-state electrolyte can significantly improve the stability of Li–O2 batteries for long-term operation by shielding the Li anode from oxygen, CO2, and moisture in the air. The solid-state electrolyte can also protect short circuiting caused by Li dendrites during long term operation.
In our study, we propose and fabricate a novel solid-state Li-O2 cell composed of a Li metal as an anode, Al2O3 as an interlayer, a perovskite-structured Al-doped Li-La-Ti-O (A-LLTO) as solid electrolyte, and a solid electrolyte integrated cathode frame covered with a carbon layer and CoO nanoparticles as catalysts for the cyclic oxygen evolution reaction and oxygen reduction reaction. In our research, we used ALD of Al2O3 as an interlayer due to its ability to prevent the direct contact between Li and A-LLTO solid electrolyte to enhance the stability of solid electrolyte against Li anode, and to form a thermodynamically stable Li ion conducting LiAlOx solid electrolyte by reacting with Li that will enhance the Li ion migration. This work demonstrates the importance of interface coupling between Li anode and solid electrolyte on the development of high performance Li−O2 batteries.
Fabrication of a Spinose Structure LiFePO4 Cathode Via Surface Etching to Improve the Rate Capability and Cycling Stability of Li-Ion Batteries
Authors: Kim Jiyong , Lim Taehoon , Martinez-Morales Alfredo A. 
Published: February 2020

Lithium iron phosphate (LiFePO4, LFP) has been demonstrated as a suitable cathode material for Li-ion batteries due to its relatively high theoretical capacity (170 mAh·g-1), cost effectiveness, long cycle life, good thermal stability, and environmental friendliness, However, key limitations of LFP are its low intrinsic electronic conductivity (10-9-10-10 S·cm-1) and limited lithium ion diffusion channel (one-dimensional path along the b-axis of the olivine structure), leading to poor rate capabilities and cycling stability in LFP batteries. To improve the rate capability of LFP cathode, the low electronic conductivity can be resolved by conductive material coating, heteroatomic doping, and downsizing of active materials.
To improve the rate capability and cycling stability of LFP battery, we propose the surface treatment of LFP cathode material to increase the surface area. The surface area of LFP is controlled by the concentration of etching agents (0.5 M to 2.0 M), etching time (10 min to 360 min), and reaction temperatures (25 °C to 80 °C). The morphology of the etched LFP surface is characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The specific surface area and crystal structure of surface etched LFP are characterized by Brunauer-Emmett-Teller (BET) and X-ray diffraction (XRD), respectively. To determine battery performance, coin-cells are assembled with cathodes containing various surface areas. Cycling testing is performed using an Arbin tester to measure the rate capability at different C-rates and cycling stability at same C-rate.
Insights into the Phase Transformation and Degradation Mechanisms of Al and Al-Alloys for Lithium-Ion Battery Anodes
Authors: Tahmasebi Mohammad Hossein , Kramer Dominik , Zheng Tianye , Mönig Reiner , Boles Steven T. 
Published: February 2020

Despite the tremendous progress made towards understanding the alloying and dealloying mechanisms in new lithium-ion battery anode materials like silicon and tin, the large volumetric changes that are intrinsic to these materials seem difficult to overcome in the absence of additional coating or nano-structuring methods that inherently increase cost and decrease capacity. Thus, the most likely candidate to replace graphite in the future may not be that which has the absolute highest capacity, but one that has an optimal balance between cost, capacity and processing complexity. Aluminum has significant advantages over other alloy anodes because of its low cost, high abundance, and wide variety of film and foil processing options. If the high theoretical capacity of aluminum (ca. 1 Ah/g or 2.7 Ah/cm3) can be even partially realized, it would be a significant improvement over conventional carbon-based anode materials. Despite the great promise of aluminum as an anode material in lithium-ion batteries, it typically suffers from fast capacity fading upon cycling. Unfortunately, the depth of knowledge concerning the degradation mechanisms of aluminum-based anode electrodes is still scarce.
In this work, aluminum and aluminum-based alloys are used to investigate the lithiation, delithiation, and degradation mechanisms in this industrially-friendly materials system. Various in situ and ex situ microscopy methods are employed, along with conventional electrochemical cycling and characterization techniques, to investigate the phase transformations associated with the Al-Li system, in particular from the α-phase (Al) to the β-phase (AlLi), during charging and discharging. Furthermore, substrate curvature methods are used which allow for quantitative insights into the mechanical properties of the film as a function of lithium content. Scanning electron microscopy investigations of the surface morphological evolution of the aluminum-based thin-film electrodes indicate that irreversible damage depends more on the depth of discharge than on the volume contraction during delithiation [1]. These results suggest that aluminum-based anodes may be highly suitable for future lithium-ion battery anodes and implications for commercially available aluminum foils as anode materials will be discussed.
[1] M. H. Tahmasebi, D. Kramer, R. Mönig, and S. T. Boles, “Insights into Phase Transformations and Degradation Mechanisms in Aluminum Anodes for Lithium-Ion Batteries,” J. Electrochem. Soc., vol. 166, no. 3, pp. A5001–A5007, 2019.