bluuebunny/crossref_metadata_2025_split huggingface dataset:
EBSD Study of 55 Wt.% Al-Zn Coating and Corrosion Behavior Effected by Austenitization Heat Treatment
Authors: Chang Jun-Kai , Yang Tzu-Chin , Lin Chao-Sung 
Published: February 2020

Reduction of CO2 emission and enhancement of fuel efficiency are an important environmental issue and the design trend of vehicle structures. Hot stamping process has been employed to for advanced high-strength steel (AHSS) parts for the automobile components. Several coating systems, such Al-Si, Zn, and Zn-Al, on the AHSS for the hot stamping process have been reported. The microstructural evolution during austenitization differs in the type of the coating, which is mainly characterized using the SEM and TEM, as well as the EDS.
Electron back-scattering diffraction (EBSD) is a kind of the crystal identification technologies. Due to the difference in the crystal orientation of phases, the phase mapping is power for detailing large-scale microstructural evolution. In this study, the EBSD was employed to identify the phase evolution of a 55 wt.% Al-Zn coated steel during different heat treatments. The result showed that the Fe2Al5 was the major phase formed at 800℃ for 5 min and no Fe-Zn IMCs was found in the coating. As the temperature of the heat treatment was increased to 900℃, the FeAl phase formed on the top of the coating and gradually became the major constituent of the coating. Moreover, the Zn did not react with the FeAl phase and gathered on the top of the coating to form the Zn-oxide. The result of pole figure indicates that the texture orientation of the FeAl phase had changed; however, the orientation change of the Fe2Al5 phase was not obvious and showed preferred orientation. Finally, the chemical stripping results show that the potential of the coating was active than the steel substrate and the potential gap between the coating and steel substrate was approximately 500 mV, which is closed to the result of Zn-coated steel without heat treatment.
Key words: 55 wt.%Al-Zn coating, EBSD, austenitization heat treatment, Fe-Al IMCs, chemical stripping

Figure 1
Electrodeposition of Adherent MnO2 Films with Optimized Current Collector Interface for 3D Li-Ion Electrodes
Authors: Vereecken Philippe M. , Timmermans Marina Y. , Mattelaer Felix , Labyedh Nouha , Zankowski Stanislaw Piotr , Detavernier Christophe 
Published: February 2020

Three-dimensional (3D) architectures for high-performance energy storage devices has been the subject of ongoing investigations targeting their integration in autonomous microelectronic systems. In this paper we present a route toward the realization of high capacity LiMn2O4 (LMO) cathode films for 3D thin-film lithium-ion batteries. One of the critical steps in the process is the electrodeposition of MnO2 coatings also known as electrolytic manganese dioxide (EMD) films. The main challenges of depositing thick enough EMD films directly on the current collector often lay in achieving a good film adhesion and preventing oxidation of non-noble current collectors such as TiN and Ni. Indeed, whereas EMD is typically used as powder for primary MnO2 based batteries and thus delamination from the current collector is desired, well adherent films are required for 3D thin-film batteries. To improve the adhesion of the EMD films we modify the surface of the current collector by means of nanometer thin seed layer coatings, which also prevent the oxidation of the underlying current collector substrate during the anodic deposition process. As a result, submicron to micron thick EMD films with good adhesion were deposited on various current collectors. The acidity of the electrolyte solutions was adjusted depending on the type of the surface coating or current collector used. The mechanism of the EMD film growth and morphology on different substrates will be discussed. Compatibility of the proposed current collector interface modification for the electrodeposition of conformal thick EMD films on high-aspect ratio microstructures was demonstrated. Finally, conversion of the EMD to LMO films is shown at low enough temperatures to be compatible with the underlying substrates. The functionality and high rate performance of the 3D LMO electrodes in Li-ion cell is demonstrated.
Figure: Electrolytic manganese dioxide (EMD) films coated conformally on high aspect ratio pillar arrays for 3D thin-film batteries.

Figure 1
(Invited) Thin Film Processing for Innovative Solid State Lithium Batteries
Authors: Oukassi Sami , Porthault Hélène , Martin Steve , Bedjaoui Messaoud , Salot Raphaël 
Published: February 2020

With the emergence of novel multifunctional internet of things and wearable electronic devices, the development of high performance energy storage devices is becoming increasingly important. Thin film solid state lithium batteries (TFBs) are known to be one of the most promising candidates to meet these applications’ demands.
In this context, it is expected that conformal deposition of additively patterned TFB layers would provide opportunities to enhance the device performance and widen the scope of possible form factor and integration schemes. Several options have been explored by our group, including key enabling technologies such as electrochemical deposition, vapor and atomic layer deposition as well as a combination thereof. Here we will discuss our efforts to develop advanced TFB architectures based on these approaches.
Surface Morphology of Copper Pulse Deposition in a Controlled Environment Using Microfluidic Device
Authors: Kawazoe Ryoma , Yamauchi Akira , Hayase Masanori 
Published: February 2020

Pulse electrodeposited copper is known for its unique characteristics. Improvement of surface roughness [1] can be expected, since the deposit consists of finer sized grain compared to that made by using direct current [2] and the edge bead due to concentration distribution of plating solution can be suppressed. These advantages are available when nearly limiting current is applied, and it is difficult to make such optimal experimental condition steadily.
In this study, we used a micro fluidic device to control the concentration of cupric ion over the electrode. Pt electrode of 100 µm in diameter was used for the working electrode, and copper for the counter and reference electrode. We use transparent glass and photoresist for the micro channel, thereby, it is possible to observe the plating process with optical microscope, externally. Flow through micro channel forcibly becomes a laminar flow, so by controlling the flow velocity and ion concentration, we can calculate the ion distribution around the electrode. From the calculation and the pulse on-time, off-time, current density, we made a simulation to figure out the experimental condition that the cupric ion depletes at the vicinity of the electrode surface (Fig.1). Applying this, we can expect a fine nucleation, depositing randomly on the electrode every time the periodic current is applied, thus we can expect a smoother deposition surface compared to that obtained by direct current plating, since the surface roughness is suppressed. SEM (JEOL Carry Scope JCM-5100) was used to observe the surface morphology of the plating. Results indicates that pulse plating suppress the hump at the edge of the plating.
References
[1]M.J.Kim, T.Lim, K.J.Park, S.K.Cho, S.Kim, and J.J.Kim, J. Electrochem. Soc., 159(9) D538-D534 (2012)
[2]J.B.Marro, T.Darroudi, C.A.Okora, Y.S.Obeng, K.C.Richardson, Thin Solid Films 621 91-97 (2017)

Figure 1
(Invited) Rational Design of Nanomaterials for Electrochemical Energy Conversion and Storage
Authors: Sun Shuhui 
Published: February 2020

PEM fuel cells are expected to play dominant role in future clean energy solutions for various applications. Developing highly efficient low-Pt and Pt-free catalysts are the key solutions for the wide-spread commercialization of PEMFCs. Through green chemistry and/or ALD techniques, we fabricated various novel Pt nanostructures, including nanowires, nanotubes, and single atoms. Compared to the conventional Pt nanoparticle/C commercial catalyst, these novel Pt nanostructures exhibited much enhanced activity (up to 10 times) and stability (up to 6 times) for fuel cells [1-7]. On the other hand, we recently developed novel Fe/N/C catalysts which exhibited higher activity in alkaline media and equivalent activity in acidic electrolyte compared to Pt. [8] Moreover, we systematically studied the decay mechanism of the MOF-based Fe/N/C catalyst, which is of significant important to improve the durability of Fe/N/C catalysts [9].
Both lithium-ion (LIB) and sodium-ion batteries (SIB) are promising technologies for energy storage. We developed a facile, inexpensive and scalable wet-chemical strategy to fabricate the Fe3O4/graphene composites and porous carbon spheres. The nanocomposite shows dramatically enhanced electrochemical properties including excellent reversible capacity, cyclability and rate performance in LIBs and SIBs [10,11].

References:

Sun, et al., Angew.
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16, 829 (2010). (Inside Cover).

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Fu, et al., J. Mater. Chem. A,
3, 13807 (2015).

Y. Fu, et al.,
RSC Advance. 6, 84149 (2016).
(Invited) Flexible Tactile Sensors for Wearable Healthcare Monitoring Devices
Authors: Ko Hyunhyub 
Published: February 2020

Flexible tactile sensors with high force sensitivities have gained great attentions in the fields of wearable devices, robotic skins, and biomedical diagnostics. In human fingertip skins, fingerprint patterns and interlocked epidermal-dermal microridges have critical roles in amplifying and transferring tactile signals to various mechanoreceptors, enabling spatio-temporal perception of various static and dynamic tactile signals. Here, mimicking the structures and functions of fingertip skin, we introduce highly-sensitive, multifunctional, and stretchable electronic skins.
Inspired by the interlocked microstructures found in epidermal-dermal ridges in human skin, piezoresistive interlocked microdomes are employed for the demonstration of stress-direction-sensitive, stretchable electronic skins. We show that interlocked microdome arrays possess highly direction-sensitive detection capability of various mechanical stimuli including normal, shear, stretching, bending, and twisting forces. We also demonstrate that ferroelectric skins with fingerprint-like patterns and interlocked microstructures can detect and discriminate multiple spatio-temporal tactile stimuli including static and dynamic pressure, vibration, and temperature with high sensitivities. For applications, we demonstrate that stretchable electronic skins attached on the human skin can be used as wearable healthcare monitoring devices, which are able to distinguish various mechanical stimuli applied in different directions, selectively monitor different intensities and directions of air flows and vibrations, and sensitively monitor human breathing flows and voice vibrations. In addition, dynamic touch sensing ability is employed for the precise detection of acoustic sounds, and discrimination of various surface textures. Finally, for multifunctional wearable and skin-attachable devices, we show smart adhesive pads with temperature-responsive adhesion properties and force-dependent color changing touch screens based on mechanochromic surface coatings.
Oxygen Evolution Reaction Investigation on Pt(111) and Ir(111) Using Dynamic Electrochemical Impedance Spectroscopy in Acidic Medium
Authors: Scohy Marion , Dubau Laetitia , Maillard Frederic , Sibert Eric , Sunde Svein 
Published: February 2020

Polymer electrolyte membrane water electrolyzers (PEMWE) are promising devices for energy conversion from electricity to chemistry. They are able to deal with important and fast changes in energy production. At the cathode compartment, the hydrogen evolution reaction occurs without kinetic limitation and practically reversibly. Nonetheless, the oxygen evolution reaction (OER) which is the anodic reaction remains a scientific challenge due to kinetic limitations and stability issues. Iridium is currently the best compromise between activity and stability [1]. However, it still undergoes degradation in the harsh oxidative and acidic operating conditions of a PEMWE [2].
The development of optimized OER catalysts is an essential step to practically implement PEMWE. A better understanding of structural effects on the catalysts activity and stability is needed. This study focuses on well-defined electrocatalysts at an atomic scale. The Ir(111) surface was characterized before and after electrooxidation and OER thanks to different electrochemical methods. A Pt(111) single-crystal, widely studied in the literature [3-4], was characterized in the same way and used as a reference. Above 1.4 vs. RHE and 1.3V vs. RHE, respectively for Pt(111) and Ir(111), the initial clean surface undergoes irreversible strucutral changes, related to the formation of defects and leading to an improvement of the oxygen evolution activity. Although classical electrochemical impedance spectroscopy (EIS) is a valuable technique when applied to stable and reversible systems, it fails with irreversible ones. Therefore, we used dynamic electrochemical impedance spectroscopy (DEIS). One can see (fig. 1) that the two methods give the same result in the reversible hydrogen adsorption area (fig.1a) while they differ for oxide formation (fig.1b) and OER (fig.1c). By analyzing the whole set of DEIS spectra, we are able to provide details on mechanism parameters for oxide formation and OER.

References

[1] Aricò, A. S., et al. (2012). "Polymer electrolyte membrane water electrolysis: status of technologies and potential applications in combination with renewable power sources." Journal of Applied Electrochemistry 43(2): 107-118.
[2] Cherevko, S., et al. (2014). "Dissolution of Noble Metals during Oxygen Evolution in Acidic Media." ChemCatChem 6(8): 2219-2223.
[3] CONWAY, B. E. (1995). "ELECTROCHEMICAL OXIDE FILM FORMATION AT NOBLE METALS AS A SURFACE-CHEMICAL PROCESS." Progress in Surface Science 49(4): 331-452.
[4] Drnec, J., et al. (2017). "Initial stages of Pt(111) electrooxidation: dynamic and structural studies by surface X-ray diffraction." Electrochimica Acta 224: 220-227.

Figure 1
Understanding and Tailoring the Performance of Transition Metal Oxides for the Oxygen Evolution Reaction
Authors: Tripkovic Vladimir , Hansen Heine A. , Vegge Tejs 
Published: February 2020

The oxygen evolution reaction (OER) is the bottleneck in direct solar and electrocatalytic water splitting cells, and rechargeable aqueous metal-air batteries. Improving the cost-efficiency of these devices requires development of efficient and cheap oxygen evolving catalysts. A good catalyst material should fulfil several important criteria: the composition and structure should be stable at conditions of interest, it should be able to conduct electrons from the active site, and it should be sufficiently active to catalyze water oxidation to oxygen.
We explore three different oxide classes comprising 1st row transition metals 1) pristine and doped Co and Ni oxyhydroxides (ox-hy), 2) pristine and doped perovskite oxides ABO3 (A is the earth-alkali or lanthanide metal and B the 1st row transition metal) and 3) pristine and doped αMnO2 as catalysts for the oxygen evolution reaction in neutral to alkaline pH. The emphasis in the analyses is placed on the three most important performance parameters: structural stability, catalytic activity and electronic conductivity.

For the ox-hy class we systematically investigate the influence of the nano-scale structure going from 3D catalysts to 2D nanosheets; we examine different edge and terrace terminations, as well as the effect of all stable metal dopants on the performance at pertinent potentials. We identify Fe doped Co, and V, Fe, Ru, Ir and Rh doped Ni ox-hys, as the best catalyst materials, out of which Rh doped Ni ox-hys exhibits the highest activity. Furthermore, we find that the electronic conductivity changes with the nature and valence of the dopant atom, which in turn depends on potential.

For the perovskite oxides, we identify Fe4+, Co3+(IS), Ni3+ and Mn3+/Mn4+ pairs as electronically conductive species and distinguish among three different conduction types: intrinsic conductance (Fe4+, Co3+(IS) and Ni3+), electron polaron hoping in Mn compounds with mixed valences and conduction via oxygen 2p and metal 3d holes in the valence band.

We investigate whether the performance of αMnO2, which according to many studies is the most active MnO2 polymorph, can be further improved by means of doping. Through a systematic approach we identify Pd doped αMnO2 to be a stable and highly active catalyst for the oxygen evolution reaction.

This work was supported by the Horizon 2020 framework, grant number 646186.
Magnesium-Ion Cathode Materials Based on the Barite Structure
Authors: Hawthorne Krista L , Liao Chen , Lau Ka-Cheong , Proffit Danielle L. , Vaughey John T. 
Published: February 2020

Lithium-ion batteries have been a mainstay of the consumer electronics industries for nearly 25 years. Unlike many older energy storage systems, lithium-ion does not describe a specific chemistry but a family of chemistries and a mechanism of operation. As a result numerous types of materials are under the umbrella of lithium-ion batteries that can be modified and developed to meet a variety of end-user goals. Looking beyond-lithium ion, the landscape is less understood and explored.
One promising area of Beyond-Lithium-Ion research has been magnesium-based systems. In this presentation we will explore the relationship between materials structure, electrolyte, and synthesis. Specific examples will be drawn from the multivalent work done by JCESR, an Energy Innovation Hub under the Department of Energy’s Office of Science. Insertion cathode materials including layered molybdates, vanadates, and related materials will be compared and contrasted to other potential host frameworks to assess limits in electrochemical performance that are driven by interfacial structure and electrolyte interactions1-5.
Figure 1. Characterization of the as made Ca ion-exchanged NaxCoO2 samples with different calcium contents. The figure shows the normalized Ca XANES, indicated by solid lines, showing the sensitivity of this method to the concentration of calcium in the layered cobaltate. CaCO3 (orange, short dash) is included for comparison since Ca0.6CoO2 is expected to have CaCO3 impurities. Ca(PF6)2 (pink, long dash) is included to show that the discriminating features are well placed as compared to the CaxCoO2 spectrum. Each spectrum is offset by an additional -0.5 on the y axis, with the exception of CaCO3 and Ca(PF6)2. Composition was measured by EDS. (from ref 5).
References

Bucur, C.B., Gregory, T, A. G. Oliver, Muldoon, J., Phys. Chem. Lett.
6, 3578−3591 (2015).

Amatucci, G., Badway, F., Singhal, A., Beaudoin, B., Skandan, G., Bowmer, T., Plitz, I., Pereira, N., Chapman, T., Jaworski, R., Journal of the Electrochemical Society, 148 A940-A950 (2001).

Ling,C., Chen, J., Mizuno, F., Phys. Chem. C, 117, 21158−21165 (2013).

Mohtadi, R., Mizuno, F., Beilstein J. Nanotechnol.
5
, 1291–1311(2014).

Proffit, D. L., Fister, T.T., Kim, S., Pan, B., Liao, C., Vaughey J., Journal of the Electrochemical Society, 163 (13) A2508-A2514 (2016).

Figure 1
Local Variation in Microstructure Causes Heterogeneity in the Conductivity of Commercial Lithium-Ion Cathode Films
Authors: Vogel John E , Hardy Emilee E , Crawford Sean , Mazzeo Brian A , Wheeler Dean R. 
Published: February 2020

Lithium-Ion battery success can be defined by a series of measureable characteristics. Two important characteristics that have been difficult to fully explore are the ionic [1] and electronic tortuosity. Micro-N-line probes were previously developed [2][3] in order to accurately measure electronic thin-film conductivity on a micro-scale.
Multiple iterations of the probe have been produced, tested and verified. In order to meet the final goal of a probe that could be implemented in any laboratory or production line, changes to the substrate, probe, and sizing were necessary. The final design also required substantial changes to methodology as well as the conductivity inversion calculations. The new probe is produced on a flexible substrate for a fraction of the original production cost and a fraction of the original production time.
Here we show that the new probe has been used to test battery films and measure battery film heterogeneity on a mm scale (See Figure 1). COMSOL modeling of the battery under testing conditions shows minimal influence by the battery current collector on measurements; this allows for non-destructive measurements of standard battery films.
The probe shows key advances in robustness and flexibility which allows for implementation on a rolling production line. New affordable stages have been developed to produce reliable measurements. High and low conductivity locations are still able to be found which is consistent with previous results.

Acknowledgements

This research is supported by the US Department of Energy through the Advanced Battery Material Research (BMR) Program.

References

[1] S.W. Peterson and D.R. Wheeler, "Direct Measurements of effective electronic transport in porous li-ion electrodes", Journal of the Electrochemical Society, vol. 161, no. 14, A2175-A2181, 2014
[2] B.J. Lanterman, A.A. Riet, N.S. Gates, J.D. Flygare, A.D. Cutler, J.E. Vogel, D.R. Wheeler, and B.A. Mazzeo, "Micro-four-line probe to measure electronic conductivity and contact resistance of thin-film battery electrodes", Journal of the Electrochemical Society, vol. 162, no. 10, A2145-A2151, 2015
[3] M.M. Forouzan, C.-W. Chao, D. Bustamante, B.A. Mazzeo, and D.R. Wheeler, "Experiment and simulation of the fabrication process of lithium-ion battery cathodes for determining microstructure and mechanical properties", Journal of Power Sources, vol. 312, pp. 172-183, 2016

Figure 1: Figure (a) showing the new probe, (b) the COMSOL model of the new probe, and (c) the results of a simple electrode conductivity mapping experiment run on a standard NMC TODA523 electrode.

Figure 1