bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Impact of Selectively Plasticized Poly (ethylene oxide) (PEO) Block in Nanostructured Polystyrene−PEO−Polystyrene Triblock Copolymer Electrolytes
Authors: Yang Guang , Cao Pengfei , Chen Xi Chelsea , Self Ethan Craig , Zhao Sheng , Ge Sirui , Zhu Chenhui , Lehmann Michelle , Saito Tomonori , Delnick Frank M. , Nanda Jagjit 
Published: February 2020

All polymer electrolytes, including block polymer (BP) electrolytes exhibit low ionic conductivity compared to liquid electrolytes. For homopolymer electrolytes, the ionic conductivity can be increased by incorporating plasticizer into the polymer network. However, the subsequent weakened mechanical structure of the network precludes its use in many practical applications. In this work, we selectively plasticize the PEO block in a polystyrene PS-PEO-PS triblock copolymer electrolyte using a PEO-like plasticizer: tetraethylene glycol dimethyl ether (TEGDME). Unlike its homopolymer (PEO) electrolyte counterpart, the mechanical properties of the PS-PEO-PS triblock copolymer electrolyte are not drastically degraded by this plasticizer because it is immiscible in the nonpolar PS block domains.
Polymer electrolyte membranes were cast from lithium trifluoromethanesulfonate (LiTFS) solutions with the corresponding polymers. The molar ratio of ethylene oxide to Li+ is 16 for all electrolytes (nEO:nLi = 16:1). The ionic conductivity of the PS-PEO-PS electrolyte at 80 °C is about one order of magnitude lower than that of the homopolymer (PEO) counterpart at the same temperature. However, the shear modulus (G’) of the PS-PEO-PS electrolyte is about three orders of magnitude higher than the homopolymer, indicating the mechanical properties of the copolymer electrolyte is primarily dominated by the PS phase. The addition of TEGDME plasticizer to the PEO homopolymer electrolyte resulted in a ~10% increase in conductivity. The addition of same amount of TEGDME to the PS-PEO-PS electrolyte resulted in ~100% increase in conductivity. Compared to the dry electrolyte counterpart, the low isothermal frequency (ω = 0.1 rad/s) elastic modulus, G’ of the TEGDME plastized PS-PEO-PS was reduced to half at 80 °C (on the order of 106 Pa). Surprisingly, G’ of the plastized membrane surpassed its dry PS-PEO-PS counterpart at higher frequency values (17 < ω < 100 rad/s).
This counter intuitive result is further explored using: 1) Fourier-transform infrared spectroscopy (FTIR) to elucidate the salt solvation and coordination to ether oxygens, and 2) small angle X-ray scattering (SAXS) to decipher the domain spacing of the adjacent copolymer blocks.
Acknowledgment
This work is supported by Dr. Imre Gyuk, Manager, Energy Storage Program, Office of Electricity Delivery and Reliability, Department of Energy. CC acknowldge partial financial support by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division.
Mitigating Li-Loss during Processing of Thin-Film Li6.22Al0.26La3Zr2O12 Solid Electrolytes
Authors: Parejiya Anand , Li Jianlin , Wood David L. 
Published: February 2020

LLZO (Li7La3Zr2O12) garnets are one of the most promising solid electrolytes for All Solid-State Batteries (ASSBs) owing to their high Li-ion conductivity and electrochemical stability against Lithium metal anode[1]. Processability is the greatest challenge with these electrolytes since it requires very thin and highly dense solid electrolytes for better performance of Li-ion batteries. ASSBs will require less than a 20-μm electrolyte to match the cycle rate performance of conventional Li-ion batteries [2]. Currently, most of the research is being carried out on compressed LLZO pellets, which are sintered in dry air at elevated temperatures to achieve higher bulk ionic conductivity. Since lithium is volatile at such high temperatures, Li-loss adversely affects performance of LLZO. Addition of 10 wt% excess lithium while synthesis of LLZO powders and covering the compressed pellets with mother-powder is often adopted to compensate Li-loss [3].
This work has resulted in the development of strategies for processing very thin film electrolytes via slurry processing. Green films as thin as 20 μm were prepared with optimized composition of binder-solvent-plasticizer system to achieve homogeneous coating. It was seen that the Li-loss is significant in thin-green-film sintering compared to compressed pellets. This phenomenon was attributed to higher surface to volume ration compared to compressed pellets, which are generally 1 mm thick. We have taken an approach of non-mother-powder based sintering for ease of post processing, which has never been reported for thin film electrolyte processing. As shown in the left figure, 75 wt% excess Li was required to compensate for Li-loss while sintering 50 μm green film. Excess Li percentages were optimized to get a pure cubic phase of LALZO after sintering green film thicknesses ranging from 20 to 100 μm. Atomic ratios of all the elements were analyzed with inductively coupled plasma - optical emission spectrometry (ICP-OES), and a compound stoichiometry of Li6.22Al0.26La3Zr2O12 was measured after sintering. The results from this work will provide a wealth of information for the first step in development of high performance inorganic solid-state electrolytes.
References:
[1] Yizhou Z,; Xingfeng H.; Yifei M.; First Principles Study on Electrochemical and Chemical Stability of Solid Electrolyte-electrode Interfaces in All-solid-state Li-ion Batteries. J. Mater. Chem. A, 2016, 4, 3253, DOI: 10.1039/C5TA08574H
[2] Advanced Research Projects Agency-Energy (ARPA-E), U.S. Department of Energy. DE-FOA-0001478. Integration and optimization of novel ion conducting solids (IONICS). 2016, (https://arpa-e-foa.energy.gov/)
[3] Inada, R.; Yasuda, S.; Tojo, M.; Tsuritani, K.; Tojo, T.; Sakurai, Y. Development of Lithium-Stuffed Garnet-Type Oxide Solid Electrolytes with High Ionic Conductivity for Application to All-Solid-State Batteries. Front. Energy Res. 2016, DOI: 10.3389/fenrg.2016.00028.

Figure 1
(Invited) Beyond Dendrites, Cycling Li-Metal across Garnet at High Current Densities
Authors: Wachsman Eric D. 
Published: February 2020

Solid-state Li-batteries (SSLiBs) have the potential to be a transformational and intrinsically safe energy storage solution. However, their progress has been limited by high solid-solid interfacial impedance and numerous reports of Li-dendrites and a corresponding “critical current density”. By first modifying the garnet surface to enable Li-metal to wet it and then fabricating garnet-electrolytes into tailored tri-layer microstructuresto form electrode supported dense thin-film (~10μm) solid-state electrolytes we have been able to overcome these limitations. The microstrucurally tailored porous garnet scaffold support increases electrode/electrolyte interfacial area, overcoming the high impedance typical of planar geometry SSLiBs resulting in an area specific resistance (ASR) of only ~2 to 7 Ωcm-2at room temperature. The unique garnet scaffold/electrolyte/scaffold structure further allows for charge/discharge of the Li-metal anode and cathode scaffolds by pore-filling, thus providing high depth of discharge ability without mechanical cycling fatigue seen with typical electrodes. Moreover, these scalable multilayer ceramic fabrication techniques, without need for dry rooms or vacuum equipment, provide for dramatically reduced manufacturing cost.
The fabrication of supported dense thin-film garnet electrolytes, their ability to cycle Li-metal at high current densities with no dendrite formation, and results for Li-metal anode/garnet-electrolyte based batteries with a number of different cathode chemistries will be presented.
(Invited) Near-Field Optical Microscopy and Spectroscopy of Nanocarbon Hybrid Materials
Authors: Ignatova Tetyana , Rotkin Slava V. 
Published: February 2020

Plasmonic properties of novel low-dimensional materials (LDMs) are promising for a range of biosensing and information technology applications. Since optical properties of LDMs can be modulated at the ultimate scale of (a few) nanometers, the characterization of these materials requires a similar spatial resolution, not available with regular tools.
Scattering-type scanning near-field optical microscope (sSNOM) allowed us to reveal such plasmonic properties of LDMs. For example, both single-wavelength and hyperspectral sSNOM imaging of graphene enables study of phonon-plasmon polariton coupling in this atomically thin layer of carbon.
Here we cover several hybrid structures based on nanocarbon materials, such as graphene and single-wall nanotubes.
SVR acknowledges help of Mr. M. Blades (Lehigh University) and Dr. T. Gokus (Neaspec). This research was partially supported by the UNCG Faculty First Award, the NSF ECCS-1509786, and Penn State Quantum Characterization Infrastructure initiative.
Optical Rectenna Arrays Using Carbon Nanotubes: From Fundamental Understanding to Next Generation Devices
Authors: Anderson Erik C. 
Published: February 2020

Optical rectennas have emerged as promising devices for high frequency optoelectronic applications such as infrared and optical sensing and energy conversion. We achieve optical rectification using vertical multiwall carbon nanotube (CNT) arrays. The CNT nanoantennas absorb electromagnetic waves and ultrafast metal-insulator-metal tunnel diodes fabricated at the CNT tips convert the resulting terahertz AC current into DC electricity.
Since the first demonstration in 2015, considerable progress to CNT optical rectennas has been made. The latest generation of CNT rectenna uses an innovative multi-insulator structure to provide exceptional diode properties and enable air stable materials. We applied photon-assisted tunneling theory to model our device’s optical-frequency behavior. Comparing the rectenna model to our optical experiments through a range of wavelengths (404–1064 nm) has yielded a better fundamental understanding that will guide future device design. The model provides strong evidence that the CNT antennas behave as dipole antennas and implicates a 780 THz diode cutoff frequency that reveals room for performance improvement.
We report ongoing research developing a novel flexible CNT rectenna device structure. We use polydimethylsiloxane (PDMS) to infiltrate the CNT array and create a mechanically flexible substrate and planarized diode surface. This structure enables transparent, conductive top electrodes with PEDOT:PSS. Our recent efforts greatly enhance the commercial development of efficient, low cost, and application tunable CNT rectennas.
Pyrolytic Carbon Films with Tunable Electronic Structure and Surface Functionality: A Planar Stand-in for Electroanalysis of Energy-Relevant Reactions
Authors: Chervin Christopher N. , Long Jeffrey W. , Sassin Megan B. , Parker Joseph F. , So Christopher R , Jeon Seokmin , Rolison Debra R. 
Published: February 2020

Nanostructured carbons are critical components within many of the electrodes used for energy-storage and –conversion systems, where they can provide pathways for electron conduction to enable high-rate operation, act as supports for other active materials (e.g., electrocatalytic metals and oxides), and contribute to the mechanical properties of the electrode. Yet often overlooked when selecting a particular carbon is the nature of electronic/chemical/physical interactions at the junction of carbon with nanoscale phases that impart desired storage or electrocatalytic functionality. Our own research with otherwise high-performing carbon-based electrode architectures suggests that sub-optimal interface design ultimately hinders energy and power capability. In order to address fundamental questions regarding interfacial processes, we step back from the complex structure of practical carbon-containing electrodes to a planar electrode configuration designed to mimic those same interfaces. For example, pyrolytic carbon (pyC) films prepared by chemical vapor deposition are planar analogs of the disordered carbon blacks used in many battery and fuel-cell electrodes, and thus serve as an electroanalytical substrate on which we deposit charge-storing metal oxides (e.g., MnO2), electroactive polymers, and metal colloids [1]. We use classical electroanalytical methods to determine fundamental properties such as electron-transfer rate constants and impedance-derived response times, absent the complexities imposed by 3D electrodes. By moving to 2D model surfaces we are also able to interrogate interfacial processes by scanning probe microscopy, including in situ monitoring of conductivity and surface morphology under potential/current control. Lessons learned from these model 2D interfaces are readily applied to the redesign of practical 3D electrode structures to improve next-generation electrochemical capacitors and batteries.
[1] J. F. Parker, G. E. Kamm, A. D. McGovern, P. A. DeSario, D. R. Rolison, and J. W. Long, Languir, 33 (2017) 9415–9425.
Corrosion Susceptibility of Austenitic Stainless Steels in Direct Carbon Fuel Cell
Authors: Mathan Bobby , Islam Monirul , Glenn Michael , Beyad Yaser , Allen Jessica A , Donne Scott W 
Published: February 2020

The direct carbon fuel cell (DCFC) is a future energy technology which is an efficient process for electrical energy generation from carbon-based sources. This technology has an extremely high theoretical efficiency due to favourable thermodynamics of the electro-oxidation reactions in the process. However, several technical challenges exist which must be addressed before the technology can be commercialized. One of the challenges is the corrosion of metal parts in the cell which limits the service life of the unit. In recent year, research on the development of new alloys and surface engineering have been done to address the corrosion issues in molten carbonate fuel cells. However, the literature on the corrosion behaviour of metals in a slurry system (coal + carbonate) is limited.
Austenitic stainless steels are known for their high temperature corrosion resistance and excellent mechanical properties. In this work, the corrosion susceptibility of two types of austenitic stainless steels, i.e. 316L (16 wt.% Cr and 10wt. % Ni) and 235 MA (21 wt.% Cr and 11 wt.% Ni) were compared for fuel cell tank body application. The corrosion behaviour of the two stainless steels were evaluated in a slurry, which contained 20 wt% coal and 80 wt% ternary-eutectic (Li2CO3: 43.5 mol%, Na2CO3: 31.5 mol%, and K2CO3: 25.0 mol%), with nitrogen as a sweep gas at 800⁰C was examined for a 30-day period. The results indicate that the weight gain (due to corrosion product build-up) for both the stainless steels was marginal after 7 day exposure, i.e., 0.4% and 0.5% for 316L and 253 MA, respectively. However, after 30 days exposure, the weight gain increased to 0.98% for 316L, whereas for 253MA the weight gain remained at ~ 0.5%. Thus, the study suggest that 235 MA stainless steel is superior to 316L stainless steel in the coal-carbonate slurry environment. The corrosion mechanisms of the stainless steels will be discussed in the presentation.
Inhibition of Hydrogen Entry into Pure Iron By Formation of Nitrogen Solid Solution Layer in the Surface
Authors: Sugawara Yu , Sawai Takuya , Hayashi Tomoki , Muto Izumi 
Published: February 2020

Hydrogen embrittlement is a serious problem for steels such as high strength steels. In order to prevent hydrogen embrittlement, the inhibition of hydrogen entry into the steel matrix is one of important subjects. The formation of surface layers with low hydrogen diffusivity is thought to be effective in inhibiting the hydrogen entry into the steel matrix. In this study, we formed nitrogen solid solution layers containing iron-nitrogen martensite and retained austenite phases on the surface of pure iron specimens by plasma-nitriding and subsequent quenching, and investigated the hydrogen permeation behavior.
Pure iron sheets of 1 mm in thickness were used as the specimens. Prior to the nitriding treatment, the specimen surfaces were polished using a diamond past down to 1 μm. The plasma nitriding treatments were carried out in a nitrogen-hydrogen atmosphere at 370 Pa for 600 s. The temperature of the specimen surface was kept at 873 K by controlling the supplied DC voltage. After the plasma nitriding, the specimens were quenched from 1073 or 1273 K for 180 s. In the case of the quenching from 1273 K, an iron-nitrogen martensite phase was formed in the surface. The thickness of the surface layer was over 100 µm. Iron-nitrogen martensite and retained austenite phases were formed in the surface of the specimen quenched from 1073 K. The thickness was ca. 50 µm.
To investigate the effect of the nitrogen solid solution layers on the hydrogen permeation behavior through the specimens, a hydrogen permeation test using a conventional Devanathan-Stachurski cell was carried out for 3.6 ks. The nitrided surface was arranged in the hydrogen entry side. Pd of 200 nm in thickness was deposited on the specimen in the hydrogen detection side. The hydrogen detection side was polarized at 0.2 V vs. SHE in 0.1 M NaOH fully deaerated by pure Ar gas. The specimen in the hydrogen entry side was polarized at −0.8 V vs. SHE in 0.1 M H2SO4. The hydrogen permeation tests reveal that the permeation current of the specimen quenched from 1273 K was smaller than that of as-polished one. The surface martensite phase seems to suppress the hydrogen permeation. In addition, no permeation current of the specimen quenched at 1073 K was detected. This is because the hydrogen diffusivity in the austenite phase is much lower than the ferrite phase due to high solubility limit in the austenite phase. The surface layer containing the austenite phase is found to be effective in inhibiting the hydrogen entry into the matrix.
Localized Corrosion Analysis Using Complex Potential Distribution Ratio as a New Transfer Function
Authors: Furukawa Noriyuki , Hoshi Yoshinao , Shitanda Isao , Itagaki Masayuki 
Published: February 2020

An electrochemical impedance spectroscopy (EIS) is powerful technique that has been used for the understanding of the corrosion mechanisms. In order to investigate the surface heterogeneities attributed to the localized corrosion, Lillard et al.1) have developed a local electrochemical impedance spectroscopy (LEIS). Because the potential differences related to the iR drop in vertical direction to the working electrode (WE) can be measured with dual microprobes in this method, the local impedance on WE can be calculated.
In the present study, our group developed a Complex Potential Distribution Ratio (CPDR) as a new transfer function to investigate the potential distributions in parallel direction to the WE. Assuming that the surface is composed of the dissolution site and oxide film site, namely, an interfacial impedance at dissolution site is lower than that at oxide film site, the current density of each site is different. In this case, the potential differences were observed in parallel direction to the WE near these sites, indicating that the iR drop of each site is different. The CPDR, Ξ, is expressed by the following equation.
Ξ = ΔV
p / ΔV
applied (1)
In this equation, the ΔV
p is the ac-potential differences between the potentials above the dissolution site, V
1, and oxide film site, V
2, in parallel direction to WE and the ΔV
applied is the ac-potential differences between WE and reference electrode in the bulk solution. In this case, the dual probes are set above the dissolution site and oxide film site to measure the ΔV
p. The impedance (Z) is expressed by the following equation.

Z = ΔV
applied / ΔI
CE (2)
In this equation, the ΔI
CE is the ac-current flowing into CE from WE.
In the present study, the Ξ and Z simulations were performed by using the equivalent circuit based on the concept. The interpretation of calculated spectra was discussed, and we applied the proposed method to the dissolution of metals.
.
Reference:
1) R. S. Lillard, P. J. Moran, H. S. Isaacs, J. Electrochem. Soc., 139 (1992) 1007-1012.
(Invited) Application of High Throughput Experimentation to Machine Learning Algorithms for the Development of Lithium Ion Battery Materials
Authors: Strand Dee , Bailey Mark 
Published: February 2020

Electrolytes for lithium ion batteries are complex formulations of solvents, salts, and additives. The formulation components affect properties of both the bulk solution and the solid electrolyte interphases on the cathode and the anode. Bulk properties, such as ionic conductivity and viscosity, are typically dominated by solvents and salts and can be predicted by models, such as the Advanced Electrolyte Model developed by Idaho National Lab. However, contributions to electrolyte performance due to additives are much more difficult to predict.
Systematic studies of electrolyte additives require evaluation of those additives in combination with a variety of solvents, salts, and other additives. The additive performance will also depend upon the active materials in the cell as well as the potentials at the anode and cathode. This presentation summarizes a practical approach to effective data gathering in such systems for use in establishing machine learning algorithms to predict performance of new formulations.
(Invited) Progress Toward Large-Format Solid-State Cells Using Sulfide Solid Electrolytes
Authors: Buettner-Garrett Josh , Becker Collin , Huang Haitao , Francisco Brian , Roberts Jason , Kelly Brandon 
Published: February 2020

Solid-state batteries are widely considered the most promising candidate to begin displacing conventional lithium ion batteries for electric vehicles and consumer electronics in the next decade, but several challenges remain. High energy density and long cycle must still be demonstrated in large automotive-relevant cells. Low cost and scalable production also need to be proven. Solid Power is working to meet these challenges by combining a sulfide-based solid electrolyte, a nickel-rich NMC cathode, and a lithium metal anode in cells that surpass conventional lithium ion in energy density and safety.
Solid Power and its collaborators have developed a suite of solid electrolytes, cathode materials, Nb-free surface treatments and production processes that deliver excellent energy density and cycle life in laboratory-scale cells. The attached figure shows early cycling performance for a recent 2 cm2 laboratory type lithium metal cell at 70°C and C/10 rate with a 4.3V charge voltage. This cell delivers 193 mAh/g based on surface-treated LiNi0.6Mn0.2Co0.2O2 (NMC622) mass and retains 191 mAh/g after 80 cycles at 100% depth-of-discharge. The excellent cycling stability of this composite cathode comes from improved electrochemical stability at the cathode-electrolyte interfaces as well as the ability to accommodate the volume changes of the NMC during cycling.
Now focus is on scaling of both cell capacity and production throughput. Cells are currently produced up to 250 mAh, and larger cells up to 20 Ah in capacity with improved performance are planned for the next year as Solid Power’s pilot scale production line is completed in early 2019. This production line is built on low-cost processes and equipment that mirror lithium ion production and will be capable of producing up to 1 MWh per month when fully operational. Remaining challenges for Solid Power include demonstrating long life with lithium metal anodes in full-scale cells and working toward low-temperature operation.

Figure 1