bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Plasma Assisted Oblique Angle Deposition of Transparent and Conductive in-Plane Anisotropic ITO Thin Films
Authors: Parra-Barranco Julian , Sanchez-Valencia Juan Ramon , Aparicio Francisco J. , Garcia-Garcia Francisco , Ferrer Francisco J. , Rico Victor , Lopez-Santos Carmen , Borras Ana , Gonzalez-Elipe Agustin R. , Barranco Angel 
Published: February 2020

Glancing angle deposited (GLAD) oxide thin films are quite interesting materials due to the wide variety of nanostructures that can be obtained with this method. Most important properties of the oxide GLAD thin films rely in the possibility to tailor their nanostructure in the form of tilted columns and other more complex forms. This nanostructure is caused by geometrical shadowing effects during the thin film growth. Porous GLAD films have been used as hosts or templates to fabricate new nanocomposite materials and other complex optical nanostructures like photonic crystals, dye sensitized solar cells, optical sensors and microfluidic devices. [1-3] In this work we study the fabrication of transparent and conducting Indium tin oxide films (ITO) by a novel synthetic approach consisting in GLAD deposition assisted by a microwave ECR plasma. The ECR microwave discharges are fully compatible with the range of pressures required for the electron evaporation process utilized for the deposition of the ITO thin films. The objective of the plasma is to modify the growth mechanism of the GLAD process in order to control the columnar microstructure, porosity and the properties of the films [4]. As it will be shown, the GLAD ITO deposition assisted by the plasma discharge is a very effective process to develop in-plane anisotropy in the ITO films what determines the films properties.
[1] M. J. Brett et al. Science, 319 (2008) 1192.
[2] A. Barranco et al. Progress in Materials Science 76, (2016) 59-153.
[2] González-García et al, Nanotechnology 23 205701, 2012.
[3] Gonzalez-García et al. Energy. Environ. Sci. 4, 2011, 3426.
[4] J. Parra-Barranco et al. ACS Appl. Mater. Interf. 7, 2015, 10993.
(Invited) Plasma Deposition of Antibacterial Nano-Coatings on Polymeric Materials
Authors: Nikiforov Anton , Leys Christophe , Kuchakova Iryna , Vanneste Myriam , Heyse Pieter , De Vrieze Mike , Zille Andrea , Dinescu Gheorghe , Mitu Bogdana , Modic Martina , Cvelbar Uros 
Published: February 2020

Non-woven textile materials with antimicrobial properties are of high demands for applications ranging from medical dressing to everyday cleaning products. We proposed a plasma assisted route to engineer polymer films and non-woven fabrics with antimicrobial nano-composite coatings. The project aims to optimize atmospheric pressure plasma deposition in order to engineer the coatings with high antibacterial activity and low cytotoxicity. Different methods of deposition are tested including radio-frequency plasma, direct current discharge in nitrogen as well barrier discharge in air with two methods of nano-particles incorporation: aerosol and impregnation. Nano-particles Ag, Cu and ZnO are tested as antimicrobial agents with average nano-particle size of about 50 nm. Nanoparticles are incorporated in between two layers of an organosilicon film with an impregnation process or alternatively through an aerosol injection step with averaged concentration of the nano-particles in the solution ranging in between 10 to 1000 mg/l. Incorporation is made in a “sandwich-like structure” where a top layer coating (barrier) of 5 - 50 nm thickness is used for precise control of metal ions release and a reservation layer of about 200 nm is used for NPs load. The effect of the barrier coating on the surface concentration of nano-particles is determined by XPS. It is shown that an increase of the thickness of the barrier layer from 5 to 25 nm leads to a decrease of Ag content from 0.24 to 0.08 at. %. Similar effect is found for nano-particles of Cu and ZnO. Antibacterial efficiency of the samples against P. aeruginosa ATCC 9027 and S. aureus M u50 bacteria shows that all treated samples exhibit higher antibacterial efficiency against S. aureus. The antibacterial efficiency of AgNPs and CuNPs is above 90% which is practically interesting for medical application while ZnONPs shows lower antibacterial efficiency. Cytotoxicity of the coatings and materials is investigated for different deposition conditions and analyzed in terms of possible medical applications.
This work is supported by the M.Era-Net project IWT 140812 “PlasmaTex”.
Copper Electrodeposition from a Water-Containing Choline Chloride-Based Deep Eutectic Solvent
Authors: Valverde Priscila , Green Todd , Roy Sudipta 
Published: February 2020

Ionic liquids are increasingly being used to electrodeposit metals, alloys and semiconductor materials. The popularity of these solvents arises from their desirable characteristics such as large electrochemical windows, reasonable conductivities, and good environmental compatibility. An important class of ionic liquids are deep eutectic solvents (DESs). DESs have been shown to be stable under atmospheric conditions, are non-flammable and have low vapour pressures. DESs formulated from choline chloride (ChCl) hold special promise since they are readily available at a reasonable cost.
The focus of this study is on ‘ethaline’ prepared by mixing choline chloride with ethylene glycol in a 1:2 molar ratio. Although DESs have been used to electrodeposition, earlier studies have concentrated on systems with a low water content (< 0.5 wt%). This is in line with earlier studies using other ionic liquids, since water can reduce the electrochemical window. However, these DES systems are hygroscopic, and absorb water from the atmosphere unless special precautions are taken. Not only can water absorption have an adverse effect on the electrochemical window, it can also affect deposit composition and morphology. Conversely, other researchers have shown that water can protect against the anodic decomposition of the solvent itself and prevent the formation of chlorinated by-products.
Information about the impact of water content on metal electrodeposition from DESs is, however, relatively scarce. The objective of this study is to understand the influence of water on the morphology of copper electrodeposited from water-containing DESs. We first examined the effect of adding various concentrations of water (3 – 15 wt%) on the stability of the solution; in particular this was obtained from the polarisation behaviour of metal deposition. It was noted that water addition affected both the limiting current for copper deposition and the deposition potential. A second series of experiments were carried out to assess how much water is absorbed by the DES depending on the storage conditions. The water content in these experiments were determined using Karl Fischer titration and NIR spectroscopy. The effect of increasing water content on copper speciation was explored using UV-Vis spectroscopy.
Subsequently, Cu films were electroplated on a steel rotating disc substrate from electrolytes containing different weight percentages of water. The deposits were characterised using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). SEM images showed that the morphology of Cu deposits was also dependent on the water content of the DES. The relationship between the observed changes in electrochemical characteristics and deposit properties with increasing water content will be discussed.
Development of a Functional Reach Compliant Trivalent Chromium Electroplating Process
Authors: Hall Timothy D , Taylor E. J. , Inman Maria , Snyder Stephen , Xu Jing , Radhakrishnan Rajeswaran 
Published: February 2020

Faraday Technology Inc. is a research, development and engineering firm developing electrochemical innovations based has pulse/pulse reverse electrolytic principles [1]. One of Faraday’s current activities is directed towards the development of an innovative functional REACH compliant chrome plating process based on a trivalent chromium electrolyte to replace hexavalent chromium plating. Hexavalent chromium plating has been used for many decades to provide hard, durable coatings with excellent wear and corrosion resistance properties. However, hexavalent chromium has come under increasing scrutiny due to the toxic nature of the bath, effects on the environment, and workers’ health. Faraday has demonstrated that the chrome coatings prepared using the FARADAYIC(R) Process have equivalent functional properties to the coatings produced with a hexavalent chromium bath. The data demonstrates equivalent or superior: 1) plating rate, 2) Knoop hardness, 3) current efficiency, 4) hydrogen embrittlement behavior, 5) adhesion, 6) corrosion resistance, 7) porosity, 8) thickness, 9) Taber Abrasion, Ball on Flat Reciprocating and Dithering wear resistance, and with no hexavalent chromium formation in the bath.
Therefore, this paper will discuss the 2013 EPA Green Chemistry Challenge Award winning work on the development of a REACH compliant functional trivalent chromium plating process from a single, simple-to-control trivalent-based electrolyte to replace hexavalent chromium plating.

Acknowledgements: This study is supported by the US Army (W911NF-11-2-0014) and private sources.
[1] E. J. Taylor “Adventures in Pulse/Pulse Reverse Electrolytic Processes: Explorations and Applications in Surface Finishing” J. Applied Surface Finsihing,
3(4), 178-189 (2008).
Molten Salt Electrorefining of Indium Metal from Indium Tin Alloy
Authors: Choi Sang-Hoon , Ali Basit , Hyun Soong-Keun , Sim Jae-Jin , Ju Won , Lim Jae-Hong , Kim Taek-Soo , Park Kyoung-Tae 
Published: February 2020

Indium is an essential element for the fabrication of transparent conductive oxide (TCO) materials. However, it is very rare element and is obtained as a byproduct of zinc metal refining. Moreover, its recycling rate is less than 1%. This provokes the need to recycle indium from its end products. Indium and tin (Sn) are especially well suited for molten salt electrolysis because of their low melting points. In this paper, reduction processes on molybdenum electrode at 500oC in molten LiCl–KCl eutectic (55.7-44.3 mol %) containing varying amount of InCl3 was studied by Cyclic Voltammetry (CV) and Chronopotentiometry (CP). In-Sn alloy was used as raw material. Thermodynamic calculations showed poor stability of InCl3 with metal based crucibles. So, Al2O3 crucible was utilized for the experiments. Concentration of InCl3 was changed from 1 wt% to 3 wt% and it was found that the reduction of indium ions take place by a two-step electrochemical reaction: In3+/In+ and In+/Ino
at the potentials of 0.78 and 0.24 V versus Ag/AgCl. Number of transferred electrons and diffusion coefficient of In+3 ion species in molten salt with varying InCl3 content was estimated with the help of CV measurements. However, at 500oC, InCl3 shows chemical reactivity with Sn metal according to the following reaction: InCl3 + 1.5Sn → 1.5SnCl2 + In. This problem was overcome by shifting the molten chloride system to molten fluoride system (LiF-KF-InF3) as fluoride based salts shows high chemical stability with metals. As a result of electrorefining, In-Sn alloy was recycled into pure indium with low levels of impurities.
Application of Iron Based Alloy Electroplating to Environmental Friendly Industries-Hydrogen Generator
Authors: Yoshihara Sachio 
Published: February 2020

Hydrogen energy system by use of water electrolysis under sustainable energy, hydro and solar power have much attention because of CO2 free, environmentally friendly zero emission system, itself. There exist the business chance, such as energy storage system to fit the demand for hydrogen stations oriented to FCV.
The development of technology to produce low-cost, large amounts of hydrogen has not been matured yet. So the research and development of the electrode for alkaline water electrolysis were important. The aim of this study is the development of the cathode with high catalytic activities and high corrosion resistance by use of electroplating process. We have already reported the performance of electrodeposited Ni-P, Ni-W-S or Ni-W-P electrode for alkaline water electrolysis. In this report we have finally found the best electrodeposited cathode, Fe-Ni-W. The characteristics for alkaline water electrolysis have been tried by linear sweep voltammetry (LSV), etc.
Alloy plating has been accomplished using electrochemical measurement system. The bath for electroplating consist of FeSO₄, NiSO₄, Na₂WO₄, H₃BO₃, H₃Cit, Na₃Cit. The substrate for plating (working electrode) was stainless steel substrate (SUS430). Before plating the substrate was washed with water and finished with nickel strike coating. Electrodeposition was performed by constant current electrolysis.
The performance as the cathode for alkaline water electrolysis was confirmed by LSV by use of saturated saturated calomel electrode (SCE) as reference electrode, Nickel electrode as counter electrode. Test solution was 30 wt % KOH aqueous solutions.
Log Exchange current density for hydrogen evolution reaction and hydrogen overvoltage obtained for thus prepared Fe-Ni-W electrode superior to those for Ni-P, Ni-W-S or Ni-W-P. The value is comparable to that for platinum electrode for acidic water electrolysis.
Anisotropic Electroless Deposition on Self-Assembled Biological Templates for Electronic Circuit Fabrication
Authors: Uprety Bibek , Harb John N. 
Published: February 2020

Biological molecules like DNA can self-assemble into a variety of complex 2-D and 3-D architectures with very low energy consumption and without the need for expensive patterning tools. In addition, self-assembled DNA templates can also be designed to controllably place functional nanomaterials with molecular precision. These characteristics make DNA an attractive template for fabricating electronic circuits from biological molecules. However, electrically conductive structures are required for electronic applications. In this study, we demonstrate a metallization process that uses gold nanorod seeds followed by anisotropic electroless plating to provide improved morphology and greater control of the final metallized width of conducting metal lines. In addition, we demonstrate the controlled placement of gold nanorods on a DNA breadboard to make rectangular, square and T-shaped metallic structures that are then completed by anisotropic plating.
Nanowire formation begins with a seeding step where gold nanorods are attached to a DNA template to create a seed layer. Electroless gold deposition is then used to fill the gaps between seeds in order to create continuous, conductive nanowires. Importantly, growth during electroless deposition occurs preferentially in the length direction at a rate that is approximately four times the growth rate in the width direction, which enables fabrication of narrow, continuous wires. The electrical properties of nanowires with widths ranging from 13 nm to 29 nm were characterized, and resistivity values as low as 8.9 X 10-7Ω-m were measured.
For site-specific placement of nanorods to a DNA template, we modified the surface of the gold nanorods with single-stranded DNA. The rods were then attached to DNA templates via complementary base-pairing between the DNA on the nanorods and the attachment strands engineered into the DNA “breadboard” template. Gaps between the nanorods were filled controllably via anisotropic plating to make continuous metallic structures of different shapes. The combination of molecularly directed deposition and anisotropic metallization presented here represents important progress towards the creation of nanoelectronic devices from self-assembled biological templates. Continuing efforts seek to interface these thin DNA metallized structures with active elements to enable device fabrication through self-assembly.
Flexible Non-Enzymatic Glucose Sensor Obtained Via Wet Metallization Coupled with Inkjet Printing
Authors: Bernasconi Roberto , Molazemhosseini Alireza , Mangogna Alessandro , Magagnin Luca 
Published: February 2020

Flexible sensors and electronic devices constitute one of the great frontiers of research in the third millennium. The advantages of these technologies are obvious: the possibility to wrap or fold the devices (with space saving benefits), the opportunity to manufacture wearable accessories and the weight reduction of the final product [1]. Many vital sectors of the modern manufacturing industry are interested by the general evolution towards flexible electronics: displays, solar cells, batteries and sensors.
In the case of biosensors in particular the development of flexible devices is particularly attractive due to their ability to adapt to human body, making possible the realization of wearable medical equipment. Example of biosensors include devices for the detection of glucose, organophosphates, proteins, antibiotics and many others. Their working principle may vary, but one of the most promising is the electrochemical one. Most of the electrochemical sensors are based on an enzyme mediated catalysis that produces or uses electrons. The resulting flux of current can be quantified and used for the sensing of the target specie.
These sensors, called enzymatic, present however some disadvantages. Firstly, the enzyme loses activity over time. Moreover, the enzyme is typically not completely stable when immobilized on a substrate. For these reasons, a primary goal of modern research on biosensing is the development of non-enzymatic sensors.
In the present work, a flexible non-enzymatic electrochemical glucose biosensor is presented. The functioning of the device is based on CuO, a common p-type semiconductor already used for the manufacturing of non-enzymatic glucose sensors [2, 3]. CuO nanoparticles are synthesized via a hydrothermal reaction and inkjet printed on a flexible substrate. Such flexible substrate is obtained by electroless plating with NiP a polymer sheet and by subsequently applying a platinum layer via electrolytic deposition. Sensitivity and selectivity of the obtained devices are finally tested with electrochemical techniques and their operative range is determined.
The obtained single use bendable sensors may result of great interest for the control of patients affected by diabetes mellitus, a pathology that constitute one of the primary health risks in the world.
[1] M. A. Alam, and S. Kumar; ed. B. Bhushan; “Flexible Electronics" chapter in Encyclopedia of Nanotechnology, Springer Netherlands, Dordrecht (2012) 860-865
[2] R. Ahmad, N. Tripathy, Y. B. Hahn, A. Umar, A. A. Ibrahim and S. H. Kim, Dalt. Trans. 44 (2015) 12488-12492
[3] R. Ahmad, M. Vaseem, N. Tripathy and Y. B. Hahn, Anal. Chem. 85 (2013) 10448-10454
High Performance, Dual-Scale Porous Carbon Electrodes for Vanadium Redox Flow Batteries
Authors: Zhou Xuelong , Zeng Yikai , Jiang Haoran , Ren Yuxun , Zhao Tianshou 
Published: February 2020

Among the many types of redox flow batteries (RFBs), the vanadium redox flow battery (VRFB) has been regarded as one of the most viable chemistries for commercialization [1]. However, one of the most challenging issues that limits its commercialization process is the high capital cost, resulting from the low-performance power-pack. The porous carbon electrode design exerts a significant influence on the battery performance, primarily because it contributes to the system polarization through not only the ohmic polarization, but also through activation polarization and concentration polarization [2, 3]. The most commonly used materials for VRFB electrodes are carbon fiber-based materials (carbon felts/papers/clothes) for their high electronic conductivity, high hydraulic permeability, chemical and electrochemical inertness. However, issues associated with the use of these materials including low specific surface area and poor electrochemical activity limit the VRFB to be operated at a low current density (~50 mA cm-2) [4].
In this work, we present a simple and cost-effective method to form different types of dual-scale porous electrodes via KOH activation of the fibers of different carbon materials, including carbon felts/papers/clothes. As shown in Fig. 1, the large pores (~10 μm), formed between carbon fibers, serve as the macroscopic pathways for high electrolyte flow rates, while the small pores (~5 nm), formed on carbon fiber surfaces, act as active sites for rapid electrochemical reactions. Hence, the dual-scale porous electrode is expected to deliver high surface area without any sacrificing in electrolyte permeability. Our preliminary results showed that Brunauer-Emmett-Teller specific surface area of these carbon materials is increased by more than 10 times and the battery assembled with dual-scale carbon-paper/cloth electrodes can even operate at 400 mA cm-2 with energy efficiency over 80%. Moreover, the dual-scale carbon-felt electrode showed stable efficiencies during more than 1000 cycles. Further characterizations and optimizations of these dual-scale electrodes and comparisons between them will be disclosed at the meeting.

References:

[1] W. Wang, Q. Luo, B. Li, X. Wei, L. Li, Z. Yang, Advanced Functional Materials. 23 (2013) 970-986.
[2] A.Z. Weber, M.M. Mench, J.P. Meyers, P.N. Ross, J.T. Gostick, Q. Liu, J. Appl. Electrochem. 41 (2011) 1137-1164.
[3] M.L. Perry, A.Z. Weber, J. Electrochem. Soc. 163 (2016) A5064-A5067.
[4] B. Li, M. Gu, Z. Nie, Y. Shao, Q. Luo, X. Wei, X. Li, J. Xiao, C. Wang, V. Sprenkle, Nano letters. 13 (2013) 1330-1335.

Figure 1
Renewable Hydrogen at Scale: An Essential Piece of the Energy Puzzle
Authors: Ayers Katherine E , Danilovic Nemanja , Gellett Wayne L. , Capuano Chris 
Published: February 2020

Increased penetration of intermittent renewable energy sources such as wind and solar is driving a need for improved energy storage technologies to manage the overall grid supply and demand, for short term fluctuations as well as long-term seasonal time variations. This challenge will require a combination of solutions, depending on geography, the mix of renewables, and other factors. At the same time, the need for a sustainable source of hydrogen has been widely recognized, not just as a potential transportation fuel, but to limit CO2 production and fossil fuel consumption from existing industrial processes such as ammonia generation. Leveraging renewable hydrogen as an energy storage solution has gained momentum through H2@Scale, an initiative to look at the synergies between intermittent renewable energy sources, industrial applications, transportation, and other grid management considerations. This talk will focus on the evolution of membrane-based water electrolysis as a renewable hydrogen pathway, and implications for industrial and energy applications.
Commercial proton exchange membrane (PEM)-based electrolysis has advanced to larger and larger scale over the last fifteen years, progressing from systems of 1 kg H2/day or less to several hundred kg/day. While leveraging the same basic manufacturing processes and technology, scale up has driven down the capital cost per kg of hydrogen by over 80%. PEM electrolysis also has tremendous potential for continuing cost reduction, leveraging system and manufacturing scaling laws as well as leveraging advancements in PEM fuel cell materials, manufacturing, and analysis tools. Order of magnitude improvements in some of the highest cost elements are easily achievable. The technology elements are known, but need to be refined and validated in a manufacturing environment, including modifications in materials and methods of fabrication. This talk will present a case study on successful implementation of cost reduced components for PEM electrolysis, opportunities for similar reduction in other components, and overall impact on cost and efficiency.