bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aluminum Corrosion Mitigation in Alkaline Electrolytes By Hybrid Inorganic/Organic Inhibitor System for Power Sources Applications
Authors: Gelman Danny , Lasman Itay , Elfimchev Sergey , Starosvetsky David , Ein-Eli Yair 
Published: February 2020

The changing and expanding needs in the energy market, ranging from power grid energy storage system to portable power sources have necessitated the development of efficient, inexpensive, and high performance battery systems to better deal with the challenges posed by the nascent green economy and non-oil based transport system. One of the promising avenues for achieving these goals is the development of aluminum battery systems based on aluminum and aluminum alloys as anodes. The main advantages presented by this system are rather low equivalent weight of the aluminum, its high natural abundance in the Earth’s crust, its low price, and its safety characteristics; also, it is substantial that aluminum and its byproducts are non-toxic and environmentally friendly. Using aluminum for these applications requires overcoming various obstacles when using different electrolyte solutions. When using aluminum in alkaline based systems the corrosion rate is very high therefore, blemishes its use in alkaline based batteries. High parasitic corrosion rate impairs the functionality of the battery due to capacity lost, dangerous hydrogen generation and significantly shorten its shelf life. Although aluminum alloys can reduce parasitic corrosion, they are frequently complex and rather expensive materials. A promising solution to the undesired corrosion is to use inhibitors which mitigate self-corrosion. Different types of inhibitors are available for use at this time, but none of them mitigate the corrosion of aluminum in alkaline solution to the extent of commercialization of a battery system. In this work, an investigation was performed on the effect of a hybrid organic\inorganic inhibitor, poly(ethylene glycol) di-acid (PEG di-acid) and zinc oxide (ZnO), in a 5M KOH solution. The inhibitors behavior on a pure aluminum was studied electrochemically, microscopically, crystallographically, and element analysis tests were performed. Moreover, the performance of aluminum air cells with alkaline solutions utilizing the hybrid inhibition approach was evaluated by galvanostatic measurements (discharge). The results of our study clearly showed that there is a distinct and strong relation between the mitigation of the corrosion to the presence and concentration of both PEG di-acid and ZnO in the solution. It was found that with the use of hybrid inhibition approach more than one order of magnitude redaction in corrosion currents and double the capacity of aluminum-air battery were achieved.

Figure 1
A Citrate-Based Coating System for AZ31 Magnesium Alloys
Authors: Chu Yu-Ren , Lin Chao-Sung 
Published: February 2020

In light of highly active chemical properties of magnesium, surface modification is always essential to control its corrosion behavior in application. Among the various modification processes, conversion coating is widely used due to its simplicity. For the past decades, many conversion coating systems, including chromate, permanganate, phosphate, stannate, and cerium-based system, have been developed. However, with ever-increasing concerns about environmental issues, a green process without the use of potentially hazardous species is required. This study thus aims at developing a citrate-based coating system for AZ31 magnesium alloys.
Prior to coating process, the AZ31 plates were abraded using emery paper up to 1200 grit, rinsed with deionized water, and dried by a stream of air. The conversion solution was applied to the AZ31 using a roll coater, and subsequently heated by hot air of approximately 75 °C for drying.
The citrate-based coating system employs trisodium citrate as solute that is dissolved in aqueous or glycerin solution. The coating formed in both solutions exhibits an identical surface morphology. However, with sulfate ions coexisting with citrate, the coating formed in aqueous solution shows a completely different morphology. Together with the change in the microstructure, the effect of sulfate ions is also observed in electrochemical analyses, including potentiodynamic polarization and electrochemical impedance spectroscopy (EIS).
To further enhance the corrosion resistance, a post treatment using a citrate-based polyamide, poly(hexamethylene succinimide-co-citramide) (PSICA), is also proposed in this study. It was found that the total impedance of the AZ31 in EIS increases from around 5,000 to 10,000 Ωcm2 after citrate-based conversion coating, and can be further elevated to near 15,000 Ωcm2 with the PSICA post treatment.
(Invited) Cr Volatility, Protective Coatings and SOFC Interconnect Testing
Authors: Froitzheim Jan , Alnegren Patrik , Falk-Windisch Hannes , Grolig Jan Gustav , Sachitanand Rakshith , Sattari Mohammad , Svensson Jan-Erik 
Published: February 2020

High chromium ferritic steels are today the most commonly considered material for SOFC interconnects due to a combination of desirable properties, such as matching thermal expansion coefficient with other cell components but most importantly better machinability and price compared to ceramic alternatives. Yet, the high operating temperature (600-900°C) causes some materials degradation issues that need to be addressed in order achieve the desired long term stability over operating periods of several 10.000h.
The main function of the interconnect is to separate the fuel compartment from one cell from the air compartment of the neighboring cell and to conduct electricity between adjacent cells. Consequently the electrical conductivity needs to remain high throughout the fuel cell stack operating life time and thus the formed oxide layers need to be electrically conductive and thin. Secondly, volatilization of chromium from the oxide scale of metallic interconnects has shown to cause detrimental effects on the cathode in SOFCs.
In the current study oxidation behavior, chromium evaporation and oxide scale resistance of ferritic steel substrates are investigated in controlled atmospheres that simulate the environment of an operating SOFC stack. Additionally samples coated with nanometer scale dual coatings of Co and Ce were tested. The dual coating substantially increased the performance of the ferritic substrates by i) significantly reducing oxidation rate, ii) increasing scale adherence, iii) diminishing chromium evaporation by 90 % via the formation of a Co-Mn-spinel cap layer and iv) substantially reducing the area specific resistance.
(Invited) Oxidation Mechanisms of Alloys for Advanced Ultra-Super Critical Steam Applications
Authors: Holcomb Gordon R 
Published: February 2020

This research supports efforts to design and build safe and cost-effective advanced ultra-supercritical (A-USC) steam boilers and turbines, with increases in energy production efficiency and reductions in emissions, including CO2. A 1 liter flowing steam autoclave, rated to 346 bar/704°C and 228 bar/760°C, was constructed and steam oxidation tests conducted. Comparison tests were run at 1 bar. Parabolic rate constants were estimated from mass change data and compared with literature values from longer duration tests—but none at this high of combined temperature and pressure. Test materials included Ni-base alloys H230, H263, H282, IN617, IN625 and IN740. At high pressures the oxide scales were thicker and parabolic rate constants one–to-two orders of magnitude higher than at 1 bar. The 1 bar data matched literature values for chromia, while the 267 bar data had a higher oxidation rate. Possible causes for increased oxidation rates with increased pressure were examined. Increased solid state diffusion within the oxide scale is quantifiable and accounts for a modest increases in expected corrosion rate and scale thickness. Increased amounts of hydrogen in the alloy, injected into the metal during steam oxidation at high pressures, may increase oxygen permeability and thus lower the ability of the alloy to establish a chromia scale—an increase in the critical Cr content for chromia scales.
Effect of Sulphur on Fe-20Cr-(Mn, Si) Alloy Corrosion in CO2-H2O Gases at 650°C
Authors: Yu Chun , Nguyen Thuan Dinh , Zhang Jianqiang , Young David John 
Published: February 2020

The oxyfuel process is a new technology in which coal combustion occurs in oxygen rather than air, producing a flue gas made up mainly of CO2 and H2O. This makes CO2 collection and sequestration feasible. The traditional low Cr martensitic steels used successfully in conventional power generation are vulnerable to corrosion in oxyfuel atmospheres. As a result, a higher Cr concentration is required to form a protective chromia scale. Because of flue gas recirculation and the lack of nitrogen dilution in the oxyfuel process, a relatively high content of sulphur is present in the gas. Although the effect of sulphur on Fe-Cr corrosion in CO2-H2O atmospheres is not clear, it is believed to be adsorbed on oxide surfaces and grain boundaries, affecting mass transport of carbon.
The present research investigates the effect of sulphur on the corrosion of Fe-20Cr, Fe-20Cr-2Mn and Fe-20Cr-0.5Si (all in wt%) alloys in Ar-20%CO2-20%H2O with and without additions of SO2 at concentrations of 0.1%, 0.5%, and 1.0%, at 650°C. Corrosion kinetics were measured via weight gains in isothermal time lapse experiments. Corrosion products were characterized using X-ray diffraction, cross-section metallography, scanning electron microscopy and transmission electron microscopy together with energy dispersive spectroscopy.
In the sulphur-free gas, Fe-20Cr and Fe-20Cr-2Mn alloys experienced breakaway oxidation, forming a thick, iron-rich oxide scale, together with extensively precipitated intergranular and intragranular carbides within the alloys. Adding SO2 to the gas significantly improved the corrosion resistance of Fe-20Cr and Fe-20Cr-2Mn alloys by forming thin protective Cr2O3/ MnCr2O4
scales. The formation of carbides was also significantly retarded due to preferential adsorption of sulphur blocking the diffusion of carbon. The Fe-20Cr-0.5Si alloy developed a protective, thin oxide scale in both sulphur-free and sulphur-containing gases. This is attributed to the formation of a thin silica layer at the chromia scale-alloy interface. This layer slowed oxide scaling by impeding outward metal diffusion, and prevented internal carburization by blocking carbon entry.
Reaction Mechanism of CaO-MgO-Al2O3-SiO2 (CMAS) Corrosion in Pyrochlore Thermal Barrier Coatings
Authors: Wang Honglong , Sheng Zhizhi , Agubra Victor , Zhang Xingxing , Tarwater Emily , Fergus Jeff W. 
Published: February 2020

Higher working temperatures improves the energy conversion efficiency in gas turbine engines so thermal barrier coatings are applied to protect the blades to increase the operating temperature. However, CaO-MgO-Al2O3-SiO2 (CMAS) from volcanic ash and other debris can lead to corrosion of the coating. Rare earth zirconates with the pyrochlore structure are promising thermal barrier materials due to their low thermal conductivity and better corrosion resistance compared to the common thermal barrier material, yttria stabilized zirconia (YSZ). CMAS reacts with the pyrochlore materials to form cubic fluorite and silicate phases which can inhibit the corrosion process. In this presentation, Gd2Zr2O7 and Sm2Zr2O7 were used to study the corrosion mechanism of CMAS on pyrochlore materials.
(Invited) A Wet Process of Copper Wiring on Surface Modified Polyimide Film By Aminosilanes
Authors: Osaka Tetsuya , Yokoshima Tokihiko , Kagawa Hiroki , Hachisu Takuma , Sugiyama Atsushi 
Published: February 2020

Polyimide (PI) film is widely used in several applications especially in the electronics industry, e.g., as a base material for ﬂexible printed wiring assembly, because of its excellent mechanical and thermal stability and a low dielectric constant. Our group proposed an all-wet process to fabricate the diffusion barrier layer and Cu wiring by using an organosilane layer as an adhesive/catalyst layer as shown in fig. 1 [1, 2]. Additionally, wet processes offer relatively simple procedures and tools, and usually are cost effective.
In previous study, an immobilized aminosilane film on polyimide works as an adhesion layer and a catalyst supporting layer for electroless deposition (ELD) of NiB. Adhesion of NiB-ELD film on ultra-smooth polyimide is a particular need for realizing a high-density printed circuit board [3]. We have reported that an induction time of NiB-ELD was changed by the number of amino groups in aminosilane, and a shorter induction time was found in the aminosilane having two or three amino groups as compared with that having single.
Our recent critical problem is in the step of Cu deposition onto NiB-ELD: a low reduction rate of cupric ion in sulfuric acid, or if the reduction proceeded, the film peeling was observed. We therefore used the alkaline electrolytes developed by Japanese company or it’s improved to fabricate Cu wiring, and examined thermal annealing effect on the electronic conductivity, crystallinity.
References
[1] T. Osaka, M. Yoshino, “New Formation Process of Plating Thin Films on Several Substrates by Means of SAM (Self-Assembled Monolayer) Process”, Electrochim. Acta, 53, 271 (2007).
[2] M. Yoshino, T. Masuda, T. Yokoshima, J. Sasano, Y. Shacham-Dimand, I.Matsuda, T. Osaka, A. Hashimoto, Y. Hagiwara, I. Sato, “Electroless Diffusion Barrier Process Using SAM on Low-k Dielectrics”, J. Electrochem. Soc, 154, D122 (2007)
[2] T. Osaka, S. Wakatsuki, T. Masuda, M. Yoshino, N. Yamachika, J. Sasano, I. Matsuda, Y. Okinaka, “A Wet Process for Forming an Adhesive Copper Layer on Polyimide Film”, Electrochemistry, 76, 191 (2008).

Figure 1
Nano Necklace Formed By Electroless Deposition of Metal on Polymer Nanofiber for Flexible Transparent Conducting Films
Authors: Shiratori Seimei , Takenaka Issei , Kyung Kyuhong , Bernasconi Roberto , Magagnin Luca 
Published: February 2020

Flexible transparent thin films are strongly required for electronic devices, display or electric equipment. To obtain both transparency and flexibility, electroless deposition on the polymer nanofiber was carried out. As the result, we successfully obtained uniformly metalized nanofiber with 300nm in diameter by all wet process without using any vacuum process.
First, we fabricated Nylon 6 nanofiber with nanoweb structure with 50nm in diameter by electrospinning method1. Then, NiP was metalized by electroless deposition on the nylon 6 nanofiber at the relatively lower temperature of 60 to 65 oC for 40 seconds2. By the Scanning Electron Microscope observation, it was found that numerous spherical shape of NiP beeds with the diameter of 300nm were tightly connected and arranged on the surface of nylon 6 nanofiber with the diameter of 50nm. It seems that same size of numerous metal beeds were formed just like “Nano Necklace” surrounding the nylon 6 nanofiber.
The electrical characteristics and the mechanical characteristics were evaluated and the possibility of the future application for the flexible transparent conductive electrodes were suggested.
References:
1)Ding, B., Li, C., Miyauchi, Y., Kuwaki, O., Shiratori, S. Nanotechnology, 2006, 17, 3685-3691.
2)Magagnin, L; Sirtori, V; Seregni, S; et al, Electrochimica Acta, 2005,50,23,4621-4625.
Fig. “Nano Necklace” formed by Electroless Deposition of NiP on the surface of Nylon 6 nanofiber

Figure 1
Control of the Magnetism of Iron Oxide Nanoparticles By Growth Parameters within Nanostructured Silicon
Authors: Granitzer Petra , Rumpf Klemens , Poelt Peter , Reissner Michael 
Published: February 2020

In the frame of this work nanostructured silicon is used as template for the deposition of iron oxide within the pores. The aim is to fabricate a nanocomposite which is appropriate to be used as vehicle for magnetic field guided drug delivery. For this reason several preconditions have to be fulfilled, e.g. no magnetic remanence at room temperature and biocompatibility of the used materials. The latter one has been evidenced by different authors before (1, 2, 3). Concerning the adjustability of the magnetic properties of the system the filling of the porous silicon with iron oxide nanoparticles has been elucidated in detail and the growth of the iron oxide structures within the pores has been investigated. The growth mechanism strongly depends on the electrolyte composition as well as on the applied potentiostatic conditions. The magnetic properties, especially the transition temperature between superparamagnetic behavior and blocked state (TB) of the nanocomposite can be controlled by the filling procedure. TB shifts to higher temperatures with increasing magnetic coupling between the particles. Dependent on the packing density as well as on the size of the particles within the pores the magnetic interactions can be modified and thus the blocking temperature can be tuned. These investigations have been carried out for particle sizes between 4 nm and 12 nm. An optimization of the magnetization (high filling density as possible) and its correlation with the blocking temperature has been carried out. An assessment of the iron oxide deposition dependent on the template and the chemical parameters as well as of the magnetic properties in dependence on the particle size, inter-particle distance and template morphology of the nanocomposite will be presented.
1. D. Ling, T. Hyeon, Small, (2012) DOI: 10.1002/smll.201202111.
2. J. Coffer, M.A. Whitehead, D. Nagesha, P. Mukherjee, G. Akkaraju, M. Totolici, R. Saffie, L. Canham. Phys. Stat. Sol (a), 202, 1451 (2005).
3. P. Granitzer, K. Rumpf, Y. Tian, G. Akkaraju, J. Coffer, P. Poelt, M. Reissner, Appl. Phys. Lett. 102, 193110 (2013).
Platinum Monolayer Perfection with the Assistance of Citric Acid in Galvanic Displacement Reaction
Authors: Shao Minhua , Brankovic Stanko R 
Published: February 2020

The slow kinetics of oxygen reduction reaction (ORR) is one of the main obstacles hindering the commercialization of low-temperature fuel cells.1 Core-shell catalysts consisting of a Pd-based core and a Pt shell (Pt/Pd/C) showed higher Pt mass activity than commercial Pt/C catalysts due to a synergistic effect between the core and Pt shell and substantially complete utilization of Pt atoms.2 The synthesis of a core-shell catalyst involves two main steps: (1) underpotential deposition (UPD) of a Cu monolayer on the surface of Pd nanoparticles; (2) displacement of the Cu atoms with Pt via a simple oxidation-reduction reaction: Cu + Pt2+ → Pt + Cu2+. The challenges associated with production of core-shell catalysts in a large scale are the uniform deposition of a Pt overlayer on the Pd core during the displacement of Cu atoms.
Herein, we report our study on the production of core-shell catalysts at the gram scale by introducing citric acid in the Pt-Cu displacement reaction solution. It was found that the quality of the Pt monolayer shell could be significantly improved by adding citric acid.3,4 In the presentation, we will discuss the role of citric acid in smoothing the Pt overlayer based on the experimental and density functional theory calculation results. The characterization and evaluation results of core-shell structures will be shown as well.
References
1. Electrocatalysis in Fuel Cells: A Non- and Low- Platinum Approach; Shao, M., Ed.; Springer: London, 2013.
2. Adzic, R. R.; Zhang, J.; Sasaki, K.; Vukmirovic, M. B.; Shao, M.; Wang, J. X.; Nilekar, A. U.; Mavrikakis, M.; Valerio, J. A.; Uribe, F. Topics in Catalysis
2007, 46, (3-4), 249-262.
3. Humbert, M.; Smith, B.; Wang, Q.; Ehrlich, S.; Shao, M., Electrocatalysis 2012, 3 (3-4), 29.
4. Shao, M. H., et al. Phys. Chem. Chem. Phys. 2013, 15, 15078
Progress in Pulse Plating Atomic Layer Deposition (PP-ALD)
Authors: Stickney John Lewellen , Czerniawski Justing , Bui Nhi , Zhang Xiaoyue , Shen Sheng 
Published: February 2020

A family of absorber materials of interest for high volume production of photovoltaics is referred to as CZTS, or Cu2ZnSn(S,Se)4. The primary advantages of these materials are that they are made from nontoxic earth abundant elements. This group has been working on electrochemical atomic layer deposition (E-ALD) as a method for the formation of PV absorber materials for many years. E-ALD involves the use of surface limited reactions to form deposits an atomic layer at a time, in order to achieve atomic layer control during the growth process. E-ALD has been based on the alternating of precursor solutions of the desired elements and the use of UPD to limit growth to an atomic layer at a time. The E-ALD method has important advantages for the formation of nanofilms of materials, including: conformal growth, atomic layer control over deposition, room temperature deposition, and scalable principles. There are a range of new PV designs involving nanostructured electrodes and plasmonic layers where the absorber layer thickness can be considerably thinner than the 4 µm used for say the formation of CdTe based thin layer photovoltaics. However, even a µm of CdTe formed using present E-ALD technology would take at least 100 time longer then the presently used industrial methods. Present E-ALD technology is can be used to grow films from a nm up, but is most applicable to where conformal, high quality nanofilms are needed. The rate of growth using E-ALD is presently limited by the time it takes to change solutions, and the solution should be changed at least twice per atomic layer. The present report involves efforts by this group to develop of a variant of E-ALD based on changing the potential, pulsing, rather than solution exchanges, greatly decreases the cycle time. Presently, the Authors referred to it as potential pulse ALD (PP-ALD). Preliminary results on the formation of Cu2Se, ZnS, and other possible binary compounds which could serve as components of a CZTS absorber layer will be discussed.
Electrochemical Oxidation of Lignin to Value-Added Chemicals
Authors: Arroyo-Torres Christian , Movil-Cabrera Omar , Staser John A 
Published: February 2020

Lignin represents a significant waste in pulping mill streams, and is generally burned during the chemical recovery process to generate heat. However, its high heating value results in a bottleneck on the pulping process, and as the only renewable raw material for aromatic compounds, it is woefully underutilized as a heat source. Our work focuses on electrochemical oxidation of lignin-rich streams to generate value-added chemicals of industrial relevance. We have begun to investigate the mechanism of lignin oxidation, in which several proceeding chemical or electrochemical reactions are possible that influence the product distribution and depend on oxidation conditions. Because lignin is soluble in alkaline solutions, we are able to oxidize lignin on inexpensive, nonprecious metal electrodes. We will present voltammetric data that show the potentials at which lignin oxidizes, and will show GC/MS results that identify lignin oxidation products as a function of oxidation conditions (i.e., potential and time). We will present our work in elucidating the mechanism that lignin undergoes during electrochemical oxidation, with an eye toward controlling the oxidation products.