bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microvia Filling By Using Insoluble Anodes in an Acidic Copper Planting Bath with a Novel Accelerator
Authors: Liu Chu-Chi , Dow Wei-Ping 
Published: February 2020

To develop copper plating formula for high-speed via filling, a more stable insoluble anode, namely dimensionally stable anode (DSA), was used at high current density. We choose a novel accelerator, 3-(N,N-dimethylthiocarbamoyl)-thio propanesulfonic acid (DPS), which has better acceleration performance on copper superfilling than Bis(3-sulfopropyl) disulfide (SPS) in the DSA plating system. This work investigates the influence of experimental conditions on filling performance and also use numerical simulation method to quantify the filling performance.
According to the results, DPS can exhibit excellent acceleration on copper deposition in the DSA plating system only. NMR result shows that DPS is oxidized by the DSA to be more active products which bears -SH and -SO3
- groups, which can accelerate on copper deposition. Putting the DSA in a filter bag can block oxygen which was produced by water electrolysis at the anodes to enter the plating solution and reduce DPS oxidation on the surface of the DSA. As a result, via bottom and top deposition rate was different from that without the filter bag.
From the results of microvia filling and numerical simulation method, the inhibition of complex inhibitor (PEG-Cl-) and the filling performance was positive in correlation with convection in the blind via. In a plating system with a strong forced convection and a low temperature exhibited better filling performance. On the other hand, the filling performance was Cu(II) mass-transfer controlled in the weakly forced convection system, so that the filling performance is not good.
The Properties of a Three-Dimensional Porous Electrode Made from Cu Nanowires
Authors: Wiley Benjamin J. , Kim Myung Jun 
Published: February 2020

The high surface area per unit volume and large mass-transfer rates offered by three-dimensional porous electrodes have resulted in their use in a wide variety of electrochemical processes, including organic electrosynthesis, water electrolysis, water treatment, fuel cells, and redox flow batteries.1-4 Many types of porous electrodes are commercially available, including carbon paper, graphite felt, reticulated vitreous carbon (RVC), metal mesh, and metal foam. Metal foam offers relatively high conductivity (1.5x10-5 ohm m) but low surface area (<4x104 m-1),5 whereas carbon paper has one of the highest surface areas (up to 1.6x105 m-1) but lower conductivity (4.7x10-5 ohm m).6

This presentation will describe the characteristics of a copper nanowire electrode (Fig. 1) that has 15 times more surface area (2.4x106 m­-1) and is 33 times more conductive (1.6x10-6ohm m) than carbon paper. The improvement in surface area is due to the small diameter of the nanowires relative to carbon fibers in carbon paper, whereas the high conductivity is due to intrinsically higher conductivity of Cu, and the fact that the metal nanowires can be sintered together, forming highly conductive inter-nanowire contacts. The porosity of the nanowire electrode is 0.94, and its permeability was only 4 times lower than carbon paper. This presentation will report the electrochemical performance of the Cu nanowire electrode relative to carbon paper for the reduction of Cu ions in a flow-through geometry. The high-conductivity, high surface area, and high porosity that can be achieved with Cu nanowire electrodes creates new opportunities for improving the performance of electrochemical systems for energy storage, hydrogen production, water treatment and the production of fine chemicals.
References:
1. J. Newman, and W. Tiedemann, AIche J., 21, 25 (1975).
2. R. Alkire, and P.K. Ng, J. Electrochem. Soc., 124, 1220 (1977).
3. J.M. Friedrich, C. Ponce-De-Leon, G.W. Reade, and F.C. Walsh, J. Electroanal. Chem., 561, 203 (2004).
4. S. Porada, L. Weinstein, R. Dash, A. van der Wal, M. Bryjak, Y. Gogotsi, and P. M. Biesheuvel, ACS Appl. Mater. Interfaces, 4, 1194 (2012).
5. S. Langlois, and F. Coeuret, J. Appl. Electrochem., 19, 43 (1989).
6. S.C. Barton, Y. Sun, B. Chandra, S. White, and J. Hone, Electrochem. Solid-State Lett., 10, B96 (2007).

Figure. 1.(A) Image of a porous Cu nanowire electrode. (B) SEM image of the nanowires in the electrode.

Figure 1
Fabrication of High-Stability Solid-State Receiver Electrodes in Exploration System for Detecting High-Resistive Gas Hydrates
Authors: Kuo Chu-Shan , Peng Hao-Ting , Lin Jeng-Yu 
Published: February 2020

Generally, gas hydrate is nearly a prefect isolator with electrical resistivity of ca. 20,000 Ω·m. Therefore, the resistivity of seafloor sediments with brine-filled pores typically ranges from 0.5 – 1.0 Ω·m, whereas sediments containing hydrate within the pores can have resistivity of ca. 10 Ω·m. As for massive blocks of hydrate, it can have resistivity of 100 Ω·m or more. Up to date, electromagnetic (EM) and direct current resistivity (DCR) techniques are generally employed to explore gas hydrate by measuring electrical resistivity. Nevertheless, both of methods still require high-stability receiver electrodes for monitoring the variance of potential difference.
In this study, the solid-state silver/silver chloride (Ag/AgCl) electrodes were successfully developed for using at high-pressure environment of deep sea. To evaluate the potential of solid-state Ag/AgCl electrodes as the receiver electrodes in EM and DCR systems, the effects of temperature, composition and flowing velocity of simulated seawater solution on the stability of the solid-state Ag/AgCl electrodes were investigated systemically. The solid state electrodes showed potential variance of ± 0.35mV at environment of room temperature or 5 ℃. Moreover, it revealed that the potential variance within ± 0.4mV when the simulated seawater solution containing 0.009 wt% bromide or 0.5wt% sulfate ion. Furthermore, it presented the potential variance within ± 0.45mV at flow rate of water in 1.5 m/s or vibration frequency at 100 Hz. Therefore, the fabricated solid-state Ag/AgCl electrode could be a promising receiver electrode candidate in EM or DCR exploration system for detecting the high resistive target, gas hydrate, under the shallow sea bead.
Innovative Separation Technology for Lithium-6 Enrichment Using Electrodialysis with Lithium Ionic Superconductor
Authors: Hoshino Tsuyoshi 
Published: February 2020

Tritium needed as a fuel for fusion reactors is produced via neutron capture by lithium-6 (6Li). However, natural Li contains only about 7.8% 6Li, and enrichment of 6Li up to 90% is required for adequate tritium breeding in fusion reactors. The mercury amalgam method is superior to some of the lithium isotope enrichment methods. In Japan, lithium isotope enrichment methods have been developed to avoid the environmental hazards of using mercury. However, the isotope separation coefficient and efficiency is too low to meet the practical need of large mass production of 6Li.
Therefore, new Li isotope separation technique using a Li ionic superconductor functioning as a Li isotope separation membrane (LISM) have been developed [1]. Li ions move by electrodialysis through LISM between the cathode and the anode in lithium solutions. Because the mobility of 6Li ions is higher than that of 7Li ions, 6Li can be enriched on the cathode side of a cell.
It has been reported that the difference in the mobility between 6Li and 7Li become large in ionic superconductor. The isotope effect in ionic superconductor is expected to be applicable to isotope separation membrane. In this research, we numerically investigated the ionic mobility of Li isotopes in ionic superconductor. Combing the first principle and the kinetics Monte Calro simulation, we calculate the diffusion constant of 6Li and 7Li. I show the two important effects for the difference in the mobility between isotope of Li. The first is the quantum effect, which decrease the diffusion barrier for Li ion and increase the ratio of the diffusion constant of Li isotopes. The second is the correlation effect between 6Li, 7Li and vacancy.
Using Li0.29La0.57TiO3 (LLTO) as the Li ionic superconductor was prepared, and the relationship between the 6Li separation coefficient and the electrodialysis time was investigated. After electrodialysis, we obtained a maximum of 1.04 for the 6Li isotope separation coefficient. This result showed that the 6Li isotope separation coefficient of this method is the same as that of the amalgamation process using mercury (1.06). Thus, this method has the potential to be a superior 6Li enrichment method to produce 90% enriched tritium breeder for fusion reactors.

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(Invited) Assessing Impacts of Material Chemistry and Operation Strategies on Capacitive Deionization Energy Consumption and Cost
Authors: Hand Steven M , Cusick Roland D 
Published: February 2020

Based on the ability to couple energy storage with ion adsorption, capacitive deionization (CDI) systems have received increased attention as an alternative to reverse osmosis (RO) desalination. Preliminary modeling indicates that CDI must operate at a charge efficiency of 0.8 or greater to compete favorably with RO. In this presentation we will highlight how critical charge efficiency can be reached by incorporating complementary fixed charge groups or faradaic materials into the electrode to enhance both selectivity and capacitance. By replacing commonly employed hydrophobic polyvinylidene fluoride (PVDF) bound electrode ionically charged structural polysaccharides, chitosan (CS) and carboxymethyl cellulose (CMC) as composite electrodes binders, we observed charge efficiency values greater than 0.9 and salt adsorption increased by a factor of three. By incorporating MnO2 onto an aerogel through electroless deposition, we improved charge efficiency to 0.8 while also increasing sodium adsorption capacity by greater than one order of magnitude. These results indicate that model informed design of CDI electrodes could enable cost effective desalination with energy storage materials.
Kinetic Modeling of Bio-Oil Conversion By Electrocatalytic Hydrogenation and Deoxygenation
Authors: Das Sabyasachi , Saffron Christopher M. 
Published: February 2020

Using renewable electricity, electrocatalytic hydrogenation can be used to stabilize biomass-derived pyrolysis oil. Stabilization occurs by electrochemically reducing highly reactive functional groups in bio-oil, such as aldehydes, ketones and aromatics, to more stable alcohols and cycloalkanes. This study develops a comprehensive kinetic model for the electrocatalytic hydrogenation of representative bio-oil compounds. The system under investigation is a two-compartment divided cell with a ruthenium impregnated activated carbon cloth cathode and a platinum anode using a Nafion membrane to separate the electrode compartments. The model, programmed in Matlab, includes mechanisms for all transient phenomena occurring in the electrolytic cell, such as bulk diffusion, intra-particle diffusion, adsorption, charge transfer reactions and surface reactions. The objective is to use this model to find rate constants and other model parameters, determine the rate-limiting steps, and identify the most sensitive variables to better understand the process and improve its performance. The development of this kinetic model is a crucial step towards scale-up of electrocatalytic hydrogenation as a keystone of novel pyrolysis-based bioenergy systems.
Electrochemical and Spectroscopic Studies of Oxidation of Biomass Mimics By Cobalt Complexes
Authors: Servedio Luke T. , Foister Shane , Zawodzinski Thomas A. 
Published: February 2020

The reactivity of cobalt(II) complexes with molecular oxygen has long been a known and is a much-studied chemical mechanism. These interactions result in the formation of metal-dioxygen adducts that are responsible for numerous cobalt-catalyzed oxidations. In the case of 4-coordinate cobalt salen [Co(salen)] complexes, the formation of catalytically active, mononuclear, superoxo adducts in the presence of a secondary, N-donor ligands has been demonstrated [Co(salen)pyr-O2]. In batch reactions, these adducts are known to readily oxidize para-substituted phenolic compounds resulting in benzoquinone in high yield. Para-phenolic model compounds have been used to demonstrate the potential use of cobalt Schiff base complexes in the oxidation of lignin biomass.
This work investigates the redox behavior of the Co(salen)pyr-O2­­ adduct as a potential recyclable electrocatalyst. Using traditional electrochemical techniques, the activity of the Co(salen)pyr-O2 adduct is evaluated as it applies to the oxidation of the substrate syringyl alcohol (4-(hydroxymethyl)-2,6-dimethoxy-phenol) in acetonitrile. Typical EC’ electrochemical behavior is reported showing a near linear relationship between substrate concentration and peak current density (Jp) up to 200 mV s-1. Electrochemical titration of catalytic amounts of Co(salen) with pyridine in the presence of excess oxygen and substrate indicate that the one-electron oxidation of Co(salen)pyr-O2H is reversible up to 2:1 pyridine to cobalt. However, both FTIR and EPR characterization of electrolysis experiments with Co(salen)pyr-O2 in the presence of excess substrate show evidence for the deactivation and/or degradation of the catalyst system after the two-hour mark indicating possible poor ligand stability under reaction conditions.

Acknowledgements

We gratefully acknowledge the NSF EPSCoR program, TN-SCORE, for support of this work.
Understanding the Economic Feasibility of Valorizing Lignocellulosic Biomass through Electrochemical Hydrogenation
Authors: Orella Michael Julian , Brown Steven Michael , Roman Yuriy , Brushett Fikile R. 
Published: February 2020

Lignocellulosic biomass presents a promising source of renewable carbon that can enable the sustainable generation of fuels, chemicals, and consumer goods that power our modern economy.1,2 While the feasibility of processing the cellulose and hemicellulose fractions of native biomass has been demonstrated, economical utilization of the lignin-containing fraction is more challenging3 due to it's chemical complexity, source-dependent structural variability, and recalcitrant nature.4,5 However, recent advances in reductive catalytic fractionation (RCF) processes have enabled clean separation of a small set of lignin monomers from the cellulose and hemicellulose fractions of native biomass, which, in turn, simplifies downstream approaches to converting these reaction products into more valuable chemicals.6,7

In this work, we investigate the potential economic feasibility of using electrocatalytic reactors, as compared to traditional thermochemical reactors, to upgrade lignin monomers to cycloalkyl and aromatic species, specifically targeting benzene, toluene, and xylene (BTX). To this end, we developed a process-based techno-economic model to quantify the viability of electrochemical upgrading, to benchmark materials and reactor performance requirements, and to identify potential technical hurdles. Furthermore, we investigate the model sensitivity to critical process parameters and key assumptions. This analysis enables a direct comparison between traditional thermochemical hydrogenation processes and proposed electrochemical hydrogenation processes across multiple installation scales as well as potentially favorable combinations of the two approaches. We hope that the results presented here inspire further research into electrochemical approaches to enable biomass upgrading.
References:
(1) Werpy, T.; Petersen, G. Top Value Added Chemicals from Biomass Volume I—Results of Screening for Potential Candidates from Sugars and Synthesis Gas; Department of Energy, 2004.
(2) Holladay, J. E.; Bozell, J. J.; White, J. F.; Johnson, D. Top value-added chemicals from biomass; Department of Energy: Pacific Northwest National Labs, 2007.
(3) Rinaldi, R.; Schüth, F. Energy Environ. Sci. 2009, 2 (6), 610.
(4) Vassilev, S. V.; Baxter, D.; Andersen, L. K.; Vassileva, C. G. Fuel 2010, 89 (5), 913.
(5) Zakzeski, J.; Bruijnincx, P. C. A.; Jongerius, A. L.; Weckhuysen, B. M. Chem. Rev. 2010, 110 (6), 3552.
(6) Bosch, S. V. den; Schutyser, W.; Vanholme, R.; Driessen, T.; Koelewijn, S.-F.; Renders, T.; Meester, B. D.; Huijgen, W. J. J.; Dehaen, W.; Courtin, C. M.; Lagrain, B.; Boerjan, W.; Sels, B. F. Energy Environ. Sci. 2015, 8 (6), 1748.
(7) Anderson, E. M.; Katahira, R.; Reed, M.; Resch, M. G.; Karp, E. M.; Beckham, G. T.; Román-Leshkov, Y. ACS Sustain. Chem. Eng. 2016, 4 (12), 6940.
Etching with Low Te Plasmas
Authors: Walton Scott G , Boris David R. , Hernandez Sandra Catalina , Rosenberg Samantha G , Miyazoe Hiroyuki , Jagtiani Ashish V , Engelmann Sebastian U , Joseph Eric A 
Published: February 2020

Processing with atomic layer precision requires the ability to not only add, remove or modify one monolayer of material but to also leave adjacent layers unchanged. This requires fine control over the flux of species and energy deposition at the surface. The appropriate threshold and process windows are certainly material specific but it is reasonable to assume many applications require low energy ions. Electron beam-generated plasmas are generally characterized by high charged particle densities (1010- 1011 cm-3), low electron temperatures (0.3 - 1.0 eV), and in reactive gas backgrounds, a relatively low radical production rate compared to discharges. The flux at the surface will thus be characterized by a comparatively large amount of ions whose energies are < 5 eV, a value commensurate with the bond strength of most materials. As such, these sources are well-suited to explore processing space not commonly found in industrial tools. In this work, we discuss SiN etching using pulsed, electron beam generated plasmas produced in SF6 backgrounds. We pay particular attention to the etch rates, selectivity (vs. carbon films, Si and SiO2), and patterning as function of operating parameters such as relative gas concentration, operating pressure, and substrate bias. These results are compared with plasma diagnostics to gain a better understanding of the process requirements and windows for threshold etching of SiN. This work is partially supported by the Naval Research Laboratory base program.
Molecular Layer Deposition for Applications in Lithium-Ion Batteries
Authors: Van de Kerckhove Kevin , Mattelaer Felix , Dendooven Jolien , Detavernier Christophe 
Published: February 2020

Molecular layer deposition (MLD) of hybrid organic-inorganic thin films called titanicones, vanadicones, tincones, and alucones was investigated for electrode and solid electrolyte applications in lithium-ion batteries.
The titanicone, vanadicone and tincone films were studied as electrode materials, both as anodes and cathodes. Novel MLD processes were developed for these materials and were based on an alkylamine metal precursor (TDMAT, TEMAV, TDMASn) and glycerol (GL) as the organic reactant. Linear and self-limited growth could be achieved for these metalcones in a broad temperature range with temperature-dependant growth rates ranging from 0.2 to 1.3 Å/cycle. Film growth was studied in situ with spectroscopic ellipsometry (SE) and infrared spectroscopy (FTIR). The as-deposited films appeared to be electrochemically inactive in all cases. A post-deposition heat treatment up to 500°C in either inert (helium) or oxidizing (air) atmosphere was able to electrochemically activate the films. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) measurements showed that all carbon was removed during calcination in air and that the films crystallized. However, annealing in inert atmosphere conserved the carbon content of the film and thus the films remained amorphous. The performance with increasing charging and discharging rate, and cyclability of the heat-treated MLD electrodes was tested against their respective metal oxide references. The He-annealed metalcones emerged from these tests as the best performing electrodes at higher rates (left and middle figures) and with improved capacity retention and stability during repeated charging and discharging.
The transformation of alucone films, deposited with the TMA and ethylene glycol (EG) or GL process, into porous aluminium oxide was examined. Porous, non-conducting materials are interesting for lithium-ion battery research since they may serve as the matrix template for solid composite electrolytes. Calcination in air and water etching proved to be the most successful methods. For the calcination treatment, a clear relation was found between the ramp rate during both heating and cooling and the resulting porosity of the film (right figure). The aging behaviour of the films in ambient atmosphere was also investigated with FTIR and showed that the films deposited with EG decompose in a matter of only a few hours, as opposed to those deposited with GL.

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(Invited) A Confined Phase Change Memory for M-Type Storage Class Memory
Authors: Kim Wanki , BrightSky Matt , Masuda Takeshi , Kim Sangbum , Bruce Robert , Carta Fabio , Fraczak Gloria , Ray Asit , Zhu Yu , Suu Koukou , Lam Chung 
Published: February 2020

Phase Change Memory (PCM) is relatively mature emerging memory technology which shows promise for serving as a Storage Class Memory (SCM) which fills the gap between high speed DRAM and much slower NAND. However, most reported PCM cells show stuck-SET failure caused by elemental segregation or open failure (void formation) as their failure mechanisms. Because of these failure mechanisms, it has been challenging to achieve the endurance specifications needed for M-type SCM. In order to overcome these well-known failure mechanisms of PCM, we advanced the state of the art confined PCM cell with a thin metallic liner.
In this study, we present a robust high aspect ratio confined PCM cell which utilizes a dense nano-crystalline-as-deposited phase change material. The small pore structures were filled utilizing an in-situ metallic liner plus nano-crystalline ALD GST process. The tuned process for depositing and integrating the phase change material yields a void-free dense confined PCM inside the pore. This confined PCM with a metallic liner is found to be immune to classic endurance failure mechanisms. So, the highly reliable confined PCM yields a new record endurance (2x1012 cycles) and a fast programming speed of 80ns with 10x switching. In addition, we thoroughly investigate the excellent endurance of the novel confined PCM with a thin metallic liner. Experimental results confirm that both the proper metallic liner and the confined pore cell structure are required for a reliability advantage. This confined PCM cell has high potential of being incorporated as a M-type storage class memory with advanced memory technology node due to its outstanding endurance and fast set speed.