bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of Electrodeposited Cu Interfaces Via Shell-Isolated Nanoparticle Enhanced Raman Spectroscopy
Authors: Raciti David , Moffat Thomas , Hight Walker Angela R. 
Published: December 2020

The advent of SERS created a new avenue for investigating interfacial phenomena by coupling the localized surface plasmon resonance (LSPR) of metal nanostructures to the inelastic scattering properties of molecules. Seeing a 104-fold enhancement in Raman signals, SERS scattering events were used to identify adsorbed molecules and substrate-surface structural conformations. But, even with the advent of SERs, Raman spectroscopy was still confined to LSPR active materials with roughened surfaces. However, recent technical modifications to SERS, such as shell-isolation and localized probe modes, have shown potential for the operando investigation of flat non-plasmon active single-crystal surfaces. Shell-isolated Nanoparticle Enhanced Raman Spectroscopy(SHINERS) provides two parallel paths for electric field enhancement of non-plasmon active surfaces while minimizing chemical perturbations by encasing reporters in a chemically inert shell (Figure 1). This technique can be used to perform measurements before, during, and after electrodeposition to gain an understanding for changes at metal-solution interfaces under an applied bias. SHINERS serves as a great utility to not only understand surface adsorbates, but to also characterize how dynamic surfaces respond to surface adsorbates. The precarious nature of metastable surfaces (e.g. metallic Cu) make capturing surface information challenging, preventing accurate structure-activity assignments necessary to fully understand the system. The lack of techniques (operando, especially) capable of evaluating functional interfaces, vs model systems, has further inhibited understanding of surface phenomena. Breaking these limits, will enable novel findings that afford new understanding and strategies to develop refined interfaces and processes. Herein, we report the synthesis of Au@SiO2 core-shell nanoparticles and their application to track the state of interfacial phenomena on electrodeposited Cu surfaces (Figure 1).
Figure 1. Electron microscopy images of Au-SiO2 nanoparticles (a) dispersed on Cu Trenches (b) for shell-isolated nanoparticle enhanced Raman spectroscopy (c) measurements to probe for surface adsorbates, which shows enhancement relative to the bare Cu surface (d).

Figure 1
Conductivity Enhancement of Aerosol Jet Printed Components By Electrodeposition
Authors: Tsui Lok-kun , Kayser Ste-ven Chase , Lavin Judith Maria 
Published: December 2020

Additive manufacturing (AM) is an attractive technique in the production of electronic components at lower cost compared to traditional circuit fabrication techniques. Aerosol jet printing (AJP), a direct write technique (Figure 1(a)), uses an atomized mist of gas directed through a nozzle to achieve high resolution (< 10 μm) linewidth prints.[1] A wide variety of inks can be printed including conducting, magnetic, and insulating materials. The standoff distance of 1-5 mm allows for both planar and conformal printing with the aerosol jet. However, the films produced by aerosol jet printing are less conductive than bulk films due to the necessity to sinter nanoparticle inks. Building thick layers to achieve the necessary conductivity is possible, but it is both time consuming and reduces the achievable resolution of the printed part. An alternative approach is to use the aerosol jet printed structure as a seed layer for the deposition of a high conductivity film by electrodeposition.
Aerosol jet printed components were made by printing 20 vol% UTDots Ag40X nanoparticle ink in 60 vol% xylenes and 20 vol% terpineol. Samples were modified by electrodeposition in a Microfab SC Cu bath (17 g/L Cu2+) with a Cu anode. Plating was performed in a 2-electrode configuration. Voltages between -0.4 and -0.5V were applied to the cell. Components modified included a transformer coil (Figure 1(b)) printed on a cylindrical ceramic bobbin. Here, modification of a 1.8 m long conductive coil reduced the resistance from 1.4 kΩ to 10 Ω. Similarly, Cu deposited on Ag traces over a 500 μm step decreased the resistance from 20-400 Ω to < 1 Ω. This technique represents a novel method to achieve both the high conductivity afforded by electrodeposition and the high resolution, low cost patterning of aerosol jet printing.

References: [1] N.J. Wilkinson, M.A.A. Smith, R.W. Kay, R.A. Harris, Int. J. Adv. Manuf. Technol. (2019), 11, 4599-4619. https://doi.org/10.1007/s00170-019-03438-2
Figure 1. (a) Simplified schematic of an aerosol jet printer. (b) Optical microscopy of transformer windings modified by electrodeposition of Cu.

SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525.
SAND2020-3906 A

Figure 1
Mechanism and Kinetics for the Electrochemical Hydrogenation and Hydrogenolysis of Furfural in Acidic Media over Copper
Authors: May Andrew , Biddinger Elizabeth 
Published: December 2020

The use of electrochemical methods provides opportunities for processes that are more sustainable then their non-electrochemical counterparts. Electrochemical processes can operate in modular format and be used to store intermittent energy in the form of produced liquid fuel. One example of a process that can be done electrochemically is the hydrogenation and hydrogenolysis (ECH) of furfural. Furfural is derived from biomass, and through hydrogenation and hydrogenolysis it can be transformed to furfuryl alcohol and 2-methylfuran which are used as a binder and a fuel, respectively. In order for processes such as furfural ECH to move towards use outside of lab research, the kinetics and mechanism must be understood to allow for efficient design of new catalysts and ECH reactors. In this work we provide insights into the kinetics of the process in acidic media and proposed potential mechanisms.
This kinetic analysis was done in acidic media of pH 0 (0.5M H2SO4) over copper flags. The kinetics of the ECH of furfural was investigated by varying the substrate concentration between 10 and 120 mM and potential between -500 and -800 mV vs RHE. The temperature was varied between 15°C to 45°C to develop Arrhenius plots and extract the activation energies of the parallel reactions.
Three mechanisms were derived and compared to the data for the ECH of furfural: non-competitive Langmuir-Hinshelwood, competitive Langmuir-Hinshelwood, and Eley-Rideal, all with the assumption that furfuryl alcohol is not an intermediate species in the formation of 2-methylfuran.
A Tutorial on the Use of Indirect Impedance to Measure Corrosion Activity in Reinforced Structural Components
Authors: Alexander Christopher Lewis 
Published: December 2020

Traditional methods capable of measuring the corrosion rate of reinforcing steel in concrete require electrical contact to the steel and are therefore destructive in cases where contact is only accessible through drilled holes into the concrete cover. Studies have shown that the application of an electric field to the surface of an electrolytic medium can indirectly polarize a metal within the solution.1 Based on this concept, an indirect impedance measurement may be used to assess the properties of steel reinforcement within concrete without an electrical contact.2,3 A four-electrode array is placed on the concrete surface and the perturbation signal is applied between the outer two electrodes while the response is measured between the inner two electrodes. As shown in the figure provided, the electrode configuration results in a nonuniform current distribution in which a portion of the injected current goes through the concrete and another portion goes through the steel. The result is an impedance response that while capable of sensing corrosion properties of the steel, is also confounded by the properties of the concrete. Therefore, challenges arise in relating the measured impedance of the system to the impedance of the steel-concrete interface. One of the challenges is establishing the sensing location and polarized surface area of the steel. Another challenge lies in determining the appropriate contribution of the concrete to the measured impedance.
This tutorial will provide a detailed description of the indirect impedance method including experimental design considerations, measurement approaches, analysis methods, and potential complications. A calibration method will be presented to relate the apparent polarization resistance to the actual polarization resistance and therefore circumvent the challenge of quantifying the steel sensing area. The necessary assumptions of the calibration procedure will be described.

C. Andrade, I. Martinez, and M. Castellote. "Feasibility of determining corrosion rates by means of stray current-induced polarisation." Journal of applied electrochemistry 38, no. 10 (2008): 1467-1476.

J. Monteiro, H. Morrison, Non-destructive method of determining the position and condition of reinforcing steel in concrete, 1999. US Patent 5,855,721.

M Keddam, X. R. Novoa, V. Vivier, “The concept of floating electrode for contact-less electrochemical measurements: Application to reinforcing steel-bar corrosion in concrete,” Corrosion Science, 51 (2009) pg. 1795-1801.

Figure 1
Lithium Plating Detection Methods in Lithium-Ion Batteries
Authors: Viswanathan Umamaheswari , Garrick Taylor R. , Fortier Mary E 
Published: December 2020

Lithium-ion batteries provide a low-cost, long cycle-life and high energy density solution to the expediting energy requirement of the automotive industry. There is a growing need of fast charging batteries for commercial application. However, large charging currents may cause Lithium plating which describes the deposition of metallic Lithium at the anode surface. It takes place at conditions of high currents and/or low temperatures because of kinetic limitations. The main reason behind plating is the slow solid-state diffusion of Lithium ions inside the active material. If the anode surface potential falls below 0 V versus Li/Li+, the formation of metallic Lithium is thermodynamically feasible. To avoid or reduce the amount Lithium plating, it is essential to detect its onset during a charging event.
Determination of accurate Lithium plating curve is crucial in estimating the boundary conditions for battery operation without compromising life and safety. There are various data analysis methods involved in deriving the Lithium plating curve: anode potential using a three-electrode cell, variation of relaxation voltage after charging (dV/dt), variation of accumulated charge with voltage (dQ/dV) and coulombic efficiency of charge/discharge with %SOC (state of charge) are more commonly employed techniques. In addition to these methods, estimation of its occurrence is typically underpinned by electrochemical models where the negative (anode) electrode potential is expressed by a set of partial differential equations based on the electrochemical and physical properties of the battery components such as the electrodes and electrolyte. The present paper reviews the common test methods and analysis that are currently utilized in Lithium plating determination. Knowledge gaps are identified, and recommendations are made for the future development in the determination and verification of Lithium plating curve in terms of modelling and analysis.
Understanding the Lithiation Pathways of Tetrel Clathrates with Synchrotron X-Ray Characterization
Authors: Dopilka Andrew , Childs Amanda , Ovchinnikov Alexander , Bobev Svilen , Chan Candace K. 
Published: December 2020

Tetrel clathrates are materials composed of cage-like frameworks of covalently bonded Group IV (Si, Ge, Sn) elements containing guest atoms in the center of each cage. Our group has been investigating the electrochemical properties of Si and Ge clathrates for potential applications as Li-ion battery anodes. Our studies have found that in some cases the Li-alloying pathways are distinctly different in clathrates compared to those seen in the diamond cubic analogs. For example, the Ba8Al16Si30 Type I clathrate does not undergo a Li-alloying reaction [1] while the Ba8Ge43 clathrate does [2]. In the case of Ba8Ge43, the reaction pathway appears to follow an amorphous phase transformation, in contrast to diamond cubic Ge, which undergoes several phase transformations to form crystalline Li-Ge phases [3].
In this work, we employ synchrotron X-ray pair-distribution function (PDF) analysis, X-ray diffraction (XRD), and in
situ heating experiments to elucidate the electrochemically induced structural changes in Ge and Sn clathrates and how they differ from those in the elemental analogs. The Type I Ba8Ge43
and Type VIII Ba8Ga16Sn30 clathrates are chosen and compared to diamond cubic Ge and beta-Sn. The PDF method allows us to probe the local structure of the amorphous phases that form after lithiation, while in situ heating experiments enable us to observe structural changes to the amorphous phases upon moderate heating. The insights learned from the structural characterizations are then used to explain the differences in the electrochemistry between the Tetrel clathrates and their elemental analogs.
The results suggest that the amorphous phases that are part of the final lithiated state of Ba8Ge43 have local structures similar to the Li-Ge crystalline phases. We conclude that the Ba atoms prevent the bulk nucleation of Li-Ge crystalline phases and restrict the Li-Ge ordering to the scale of 10-15 Å, resulting in a solid solution mechanism and a lower reaction voltage compared to cubic-Ge. Similar analysis of the Type VIII Ga-Sn clathrate (Ba8Ga16Sn30) results in a similar lithiation path showing a solely amorphous phase transformation. These results give insight to the fundamentals of how the initial structure of group IV materials affect their Li-alloying properties and structures.

Figure 1 (a) Unit cell of Ba8Ge43, purple atoms are Ge and green atoms are Ba. (b) PDFs of the lithiation of Ba8Ge43 at different states of lithiation. (c) PDFs of cubic-Ge at different states of lithiation.
[1] R. Zhao. ACS Appl. Mater. Interfaces. 9 (2017) 41246–41257.
[2] A. Dopilka. ACS Appl. Mater. Interfaces. 10 (2018) 37981–37993.
[3] H. Jung. Chem. Mater. 27 (2015) 1031–1041.

Figure 1
Zinc and Nickel Based Oxides Anchored Onto Nitrogen-Doped Carbon Nanotubes As Bifunctional Catalysts for Zinc-Air Batteries
Authors: McDougall Alexandra , Assen Drew , Ivey Douglas G 
Published: December 2020

Rechargeable zinc-air batteries are a promising battery technology as they are safe, environmentally friendly, low cost, and have a high theoretical energy density. However, there are several challenges with zinc-air batteries which occur mainly at the air electrode. The main challenge is the slow reaction kinetics for the oxygen evolution and reduction reactions (OER/ORR). To improve the OER and ORR precious metal catalysts have typically been added to the air electrode. However, using precious metals as catalyst materials inhibits large scale applications due to the high material cost and material scarcity. Transition metal oxides are an effective lower cost alternative. Combining transition metal oxides with nanocarbon structures can further increase OER and ORR rates and improve electrochemical stability. [1], [2]
In this study, a combination of nitrogen-doped nanotubes (N-CNTs) and transition metal oxides is impregnated into a gas diffusion layer (GDL) made from porous carbon paper. This synthesis process ensures that the catalyst is present throughout the GDL, improving the reaction kinetics [2]. Zinc- and nickel-based tri-metallic and tetra-metallic oxides are investigated. Nickel-based oxides have demonstrated potential for high electrochemical activity but have not been fully studied [3]. Zinc is chosen, in part, because it appears to be incorporated into the transition metal oxide catalysts during battery cycling, so its effect on battery behavior is worth further study. The metal oxide combinations are determined from previous bi-metallic and initial tri-metallic oxide results. For each combination, different ratios are tested, since the amount of each transition metal affects the OER and ORR kinetics. Each combination is examined through various electrochemical and microstructural characterization techniques; e.g., linear sweep voltammetry, electrochemical impedance spectroscopy, electron microscopy and energy-dispersive X-ray spectroscopy. A Design of Experiments approach is used to determine the best metal ratios for each combination. The overall goal of this work is to find a catalyst that increases the efficiency, lowers the voltage gap, and improves the cyclability of zinc-air batteries.
[1] N. Xu et al., “Self-Assembly formation of Bi-functional Co 3 O 4 /MnO 2-CNTs hybrid catalysts for achieving both high energy/power density and cyclic ability of rechargeable zinc-Air battery,” Sci. Rep., vol. 6, no. September, pp. 1–10, 2016.
[2] D. Aasen, M. Clark, and D. G. Ivey, “ A Gas Diffusion Layer Impregnated with Mn 3 O 4 ‐Decorated N‐Doped Carbon Nanotubes for the Oxygen Reduction Reaction in Zinc‐Air Batteries ,” Batter. Supercaps, vol. 2, no. 10, pp. 882–893, 2019.
[3] J. Yi et al., “Non-noble Iron Group (Fe, Co, Ni)-Based Oxide Electrocatalysts for Aqueous Zinc-Air Batteries: Recent Progress, Challenges, and Perspectives,” Organometallics, vol. 38, no. 6, pp. 1186–1199, 2019.
Ambient Na-S Discharge Mechanisms in Glyme Electrolytes Identified with in-Situ Optical Microscopy
Authors: Carter Rachel E. , NewRingeisen Addison , Reed Daniel , Sassin Megan B. , Mukherjee Partha P. , Love Corey T. 
Published: December 2020

Ambient Na-S systems have regained attention as global abundance of materials becomes a concern for Li-ion batteries.1 The fundamental Na-S system consists of a sulfur cathode, liquid electrolyte and a sodium anode, and it can be informed by discoveries in Li-S and Li metal battery research. Early Li-S research identified the propensity for various Li-S discharge products to solubilize in the electrolyte. This behavior proved crucial to performance. Because the analogous solubilized Na-S discharge products have distinct colors in the visible spectrum, we employ a specially designed in-situ electrochemical cell, developed at the Naval Research Laboratory,2 to track electrolyte color during discharge. This optical tracking allows the identification of the chronology of solubilized discharge products and assess the efficacy of promising electrolytes. The discharge products (Na2Sn, 8<n<1) and relative quantities are determined via their distinct colors, and UV-vis calibration, respectively. Since these behaviors prove strongly dependent on electrolyte solvent and salt concentration, the study is valuable to selection of the optimal composition for anode stability and cathode performance.
1.Carter, R.; Oakes, L.; Douglas, A.; Muralidharan, N.; Cohn, A. P.; Pint, C. L., A Sugar-DerivedRoom-Temperature Sodium Sulfur Battery with Long Term Cycling Stability. Nano Letters 2017, 17 (3),1863-1869.
2.Love, C. T.; Baturina, O. A.; Swider-Lyons, K. E., Observation of Lithium Dendrites at AmbientTemperature and Below. Ecs Electrochem Lett 2015, 4 (2), A24-A27.
Phase Transformation in Germanium-on-Insulator (GeOI) Films Using Raman Spectroscopy and Nanoindentation
Authors: Mohammed Yousuf , Zhang Kai , Heissler Stefan , Baumgart Helmut - , Elmustafa Abdelmageed 
Published: December 2020

Germanium-on-insulator (GeOI) films fabricated using the SMART CUT wafer bonding and film exfoliation technology were investigated for the mechanical properties and induced phase transformations by using nanoindentation and Raman spectroscopy experiments. The hardness and modulus results of the GeOI films are significantly different from the published SOI literature and bulk germanium results obtained by Liu et al., 2020 [1] and SOI films results obtained by Miller et al., 2007 [2]. From our measured hardness results of 8 to 10 GPa for very thin single crystal Ge(100) films compared to 13.1 GPa for Bulk Ge (100), one can conclude that the thinning of crystalline Ge films leads to a considerable softening of the crystalline Ge resulting in less brittle robust films. Similarly, our measured modulus of 130 to 140 GPa for thin Ge (100) films compared to the reported bulk Ge (100) value of 157 GPa corroborates these research findings. The GeOI films are softer and more flexible as compared to bulk Ge hardness and stiffness properties. The Raman spectroscopy of the spherical indents indicate bands of metastable Ge phases @ 220 cm-1, 195 cm-1 and 184 cm-1 wavenumbers. Our results demonstrate that a spherical indenter impacted a wider area of contact and produced GeOI indented surfaces free of cracks and fracture. The spherical indenter tip kept the Ge top layer intact when compared to the Berkovich indenter tip during penetration. In contrast, the Berkovich indenter tip developed excessive fracture that resulted in displacing the Ge top layer sideways and exposed the Si substrate underneath revealing Raman spectra bands of metastable Si phases @ 350 cm-1, 399 cm-1 and 430 cm-1.
Apart from the well documented electrical advantages of GeOI, the reported research on the nanomechanical properties reveals considerable softening and flexibility of the very thin exfoliated single crystal Ge films that promise added benefits and further implications for enhancing potential device application of GeOI wafers for process integration.
1.] N. Liu, X-J Yang, Z. Yu, and L. Zhao, Trans. Nonferrous Met. Soc. China, 30, 181 (2020).
2.] N. Miller, K. Tapily, H. Baumgart, G.K. Celler, F. Brunier, and A.A. Elmustafa, Mater. Res. Soc. Symp. Proc. Vol. 1021 © 2007 Materials Research Society, 1021-HH05-24. Boston, Massachusetts. (2007).