bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Reference Electrodes for Air and Moisture Stable Ionic Liquids
Authors: Horwood Corie , Stadermann Michael 
Published: February 2020

The use of room temperature ionic liquids (RTILs) for electrochemical applications such as fuel cells, batteries, dye-sensitized solar cells, and supercapacitors, has gained significant interest over the last decade. Despite the increase in attention, a universal reference electrode for use in RTIL electrochemistry has not been adopted. A stable, easy to prepare, and reproducible reference electrode, analogous to Ag/AgCl reference electrodes for aqueous electrochemistry, is crucial for accurately determining redox potentials as well as for comparing these potentials between RTILs and between research labs.
Electrochemical work in RTILs often rely on quasi-reference electrodes (QREs),1 such as Ag or Pt wire, which must be calibrated by the addition of a redox couple (e.g. ferrocene/ferrocenium) after each electrochemical measurement. These quasi-reference electrodes are difficult to reproduce, likely due to the quality of the wire used and the presence of surface adsorbates. Furthermore, they have been known to exhibit potential drift during use, with 10s to 100s of mV drift often observed. Ferrocene is added after the experiment, however this one-point calibration of the QRE does not necessarily apply throughout the entire experiment, as the QRE may drift during the measurement.2

We report on reference electrodes designed for use in ionic liquids, which exhibit stable potential over several months of experimental use. One successful example is based on a silver wire coated with silver sulfide.3 The reference electrode potential is determined by the concentrations of Ag+ and S2
−, which are established by the solubility of the Ag2S coating on the Ag wire. Our reference electrode can be prepared and used in a normal air atmosphere, and does not need to be assembled and used in a glovebox, or protected from light. The reference electrode has been characterized by voltammetry measurements of ferrocene and cobaltocenium hexafluorophosphate, and was found to slowly drift to more positive potentials at a rate of <1 mV/day for five RTILs investigated over the course of 2+ months.
This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. IM release LLNL-ABS-748348.
(1) Electrochemical aspects of ionic liquids, 2nd ed.; Ohno, H., Ed.; John Wiley & Sons Inc., 2011.
(2) Torriero, A. A. J.; Sunarso, J.; Howlett, P. C. Electrochim. Acta
2012, 82, 60–68.
(3) Horwood, C.; Stadermann, M. Electrochem. Commun.
2018, 88 (December 2017), 105–108.
Kinetics of the Reduction of Rare Earth Metals in LiCl–KCl–Cscl Eutectic Melt
Authors: Shchetinskiy Andrey V. , Kharina Ekaterina A. , Volkovich Vladimir A. , Dedyukhin Alexander S. 
Published: February 2020

Modeling and developing high temperature processes involving rare earth metals relies on comprehensive data concerning their behavior in molten salt media. The aim of the present study was determining kinetic parameters of reduction of lanthanum, praseodymium and neodymium ions in the melts based on the ternary eutectic mixture of lithium, potassium and cesium chlorides. The experiments were performed at 400–750 oC on a tungsten working electrode employing cyclic voltammetry and chronopotentiometry. Potentials were measured vs. chlorine reference electrode.
Reduction of Ln(III) ions to Ln(0) for all the elements studied occurred as a single stage process. The process is reversible and controlled by diffusion. Transition time of the process was determined and diffusion coefficients of Ln3+ ions calculated.
(Invited) Cellulose and Ionic Liquids Beyond Dissolution
Authors: Byrne Nolene 
Published: February 2020

Cellulose finds use in a wide variety of applications and owing to its renewable abundant nature the use of cellulose in new applications is increasing. The ability of ionic liquids to dissolve cellulose was a catalyst for significant ionic liquid development and research in the early 2000’s to present day. Many applications and research papers exist on the topic of ionic liquids and cellulose from understanding dissolution mechanisms to developing functionalized forms of cellulose. In this talk, our efforts on processing cellulose and other lignocellulose types with ionic liquids will be discussed covering topics from spinning regenerated cellulose fibres to the development of cellulose aerogels with tunable pore structures, including recycling textiles materials using ionic liquid solvents. The influence of dissolution and regeneration is a common theme for each of these processes and impacts the properties of the final material. Application properties will also discussed.
Figure 1:
Aerogels produced using different ionic liquids resulting in different pore morphology and mechanical properties.
Figure 2:
Regenerated lignocellulose fibres produced under different draw and different solvents: below carbon fibre from regenerated lignocellulose precursor

Figure 1
New Co-Electrolysis Cell Design with Improved CO2 Reduction Efficiency
Authors: Patru Alexandra , Pribyl Bernhard , Schmidt Thomas J. 
Published: February 2020

Electrochemical CO2 reduction it is an attractive method for minimizing the level of atmospheric CO2 and storing energy 1
,
2. When this process is coupled to a renewable energy source such as wind or solar, carbon dioxide is converted to fuels or chemical feedstock. To reduce important quantities of CO2, specific devices named co-electrolyser are needed. For high efficiency of these devices several parameters need to be integrated: i) active cathode catalyst for CO2 reduction reaction (CO2RR), ii) optimal cathode pH, iii) adequate polymer electrolytes when the CO2RR takes place from gas phase and iv) rational engineering for low energy consumption.
Our work presents the design of a new co-electrolysis cell operating at low temperature (i.e. 40°C) where not liquid electrolyte is used for CO2RR. This new cell configuration made use of a standard Nafion® cation exchange membrane in combination with a modified cathode catalyst layer preparation: an alkaline anion exchange ionomer was used within the cathode catalyst layer, and an additional thin film of the same alkaline ionomer was coated on the cathode catalyst layer in order to prevent direct contact between the cathode catalyst and the acidic cation exchange membrane. Different types of silver catalysts are investigated under this configuration 3. The cells faradaic and energetic efficiencies are compared with those obtained for the same catalysts in standard three electrode cells using liquid electrolytes4.

References

J. Durst et al., Chimia, 69, 769–776 (2015).

J. Herranz et al., Nano Energy, 29 (2016).

A. Dutta, M. Rahaman, N. C. Luedi, M. Mohos, and P. Broekmann, ACS Catal., 6, 3804–3814 (2016).

K. P. Kuhl, E. Cave, D. N. Abram, and T. F. Jaramillo, Energy Environ. Sci., 5, 7050–7059 (2012).

Acknowledgements

Financial support of this work by the Swiss Innovation Agency (Innosuisse) and the Swiss Competence Center for Energy Research Heat and Electricity Storage are greatly acknowledged.
(Invited) Oxide Nanowires Array Based CdSe/CdS/TiO2 1-D Heterojunction Photoelectrode for Enhanced Solar Fuel Conversion
Authors: Lee Jung-Kun , Han Gillsang , Caliskan Salim 
Published: February 2020

Production of hydrogen by photoelectrochemical system has received considerable interest as one of the promising route without generation any undesired pollutants. A major component of a photoelectrochemical (PEC) water splitting system is the photoelectrode where critical processes such as light harvesting, generation of charge carriers, minority carrier migration towards its interface with the electrolyte, as well as majority carrier transportation towards the external circuit for water splitting. Co-sensitization by double-shell of QDs (e.g., CdSe/CdS) for the TiO2 or ZnO nanostructures demonstrated a large PEC performance improvement due to their extension of light absorption range. A sequential coating of two different light absorbers on the electrode (e.g. CdS/CdSe multilayer structure on TiO2) forms terraces in their band diagram (i.e, type II heterojunction), thus the aligned band edge promotes separation of electrons and holes and cascade-like carrier transport at their interface, and thereby increases the photocurrent The deposition of these QDs on one-dimensional (1-D) nanostructures of semiconductor including nanowires/nanorods (NWs/NRs) and nanotubes (NTs) increases the charge transport properties by providing a “highway” for electron travel. Although a few recent studies have shown that the ITO NWs improves the charge transport/collection for a single layer light absorber, their overall PEC performance is still lower than theoretically expected value because the photoelectrode absorb only a part of visible light (by a single layer absorber) and/or photo-generated charge carriers are largely recombined in the light absorber layer due to a low charge separation efficiency.
In the present study, we employed In2O3 and SnO2 NWs as a support for the CdSe/CdS/TiO2 multi-shelled heterojunction photoelectrode to demonstrate a largely enhanced PEC hydrogen production by improving the charge transport property. PEC performance of the resultant CdSe/CdS/TiO2/ITO NWs photoelectrode for the hydrogen production was investigated and they are compared with those of a planar structured and m-TiO2 nanoparticles based CdSe/CdS heterojunction photoelectrodes. The resultant 1-D heterojunction photoelectrode (CdSe/CdS/TiO2/ITO NWs) shows improved light absorption and charge transport properties in comparison to the planar structured photoelectrode (without the ITO NWs) and mesoporous TiO2 nanoparticles film based photoelectrode. We found that the ITO NWs based CdSe/CdS/TiO2 multi-shelled photoelectrode exhibits photocurrent density of ~16.2 mA/cm2, which is 2.4 times higher than that of m-TiO2 nanoparticles based photoelectrode and even outperforms previously reported TiO2 or ZnO NWs based photoelectrodes.
Amperometric Sensing of Bilirubin By the Ionic Liquid Doped Imprinted Polymer Modified Electrode
Authors: Syu Mei-Jywan , Tseng Yan-Di 
Published: February 2020

Bilirubin is a metabolite of hemoglobin. Concentration of bilirubin in serum is often regarded as an important physiological indicator for judging the liver disease. In this work, molecularly imprinted polymer (MIP) doped with room-temperature ionic liquid (RTIL) and bilirubin template molecule was fabricated onto the surface of Au electrode. Both methacrylic acid (MAA) and ethylene glycol dimethyl acrylate (EGDMA) were used as the functional monomers. EGDMA was also used as the corsslinker. 1-Butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([BMIM][TF2N]) was the chosen RTIL. Together with bilirubin, the bilirubin-imprinted [BMIM][TF2N]-d-poly(MAA-EGDMA) ([BMIM][TF2N] doped poly(MAA-co-EGDMA)) was synthesized onto the Au surface. The SEM images showed that the polymeric film thus prepared was rather uniform and the average thickness was approximately 1.98 μm. After the extraction by a proper solvent, most bilirubin (the imprinted template molecule) was removed from the imprinted [BMIM][TF2N]-d-poly(MAA-EGDMA) film. Consequently, specific binding cavity for bilirubin was created after the extraction. Via which, electrochemical sensing of bilirubin by the amperometric mode owing to the specific interaction of the polymer film with bilirubin template would become feasible.
RTIL could enhance the amperometric signal of the MIP electrode. The imprinting factor of 5.52 ± 0.09 and the detection sensitivity of 0.367 ± 0.019 μA/cm2/mg/dL for bilirubin were achieved, respectively, from the imprinted [BMIM][TF2N]-d-poly(MAA-EGDMA) modified Au electrode. The RTIL doped MIP electrode is even able to detect bilirubin in the low concentration ranging from 0.2 to 1.0 mg/dL. The selectivity of bilirubin against biliverdin was 2.13. Additionally, the MIP electrode could discriminate bilirubin in the presence of serum. In summary, the experimental results confirm the feasibility of the RTIL-MIP electrode for the detection of bilirubin in serum.

Keywords: bilirubin, molecularly imprinted polymer (MIP), room-temperature ionic liquid (RTIL)
References

MJ Whitcombe. J Mol Recognit 19, 106–180 (2006)

M Opallp, A Lesniewski. J Electro Chem 656, 2–16 (2011)

AH Wu, MJ Syu. Biosens Bioelectron 21(12), 2345–2353 (2006)
Organic Skin Patch with Built-in Enzymatic Fuel Cell
Authors: Nishizawa Matsuhiko 
Published: February 2020

We have developed totally organic electric patch with built-in enzymatic biofuel cell (BFC) for producing iontophoretic current flowing “on-skin” or “through skin”. The skin patches consist of stretchable enzyme electrodes, elastic conductive resistor, hydrogel sheet, and O2-permeable medical adhesive tape. We used fructose / O2 system because the enzymes for oxidation of fructose (fructose dehydrogenese) and reduction of O2 (bilirubin oxidase) can work without the presence of electron mediators for electrocatalysis, resulting in a simple configuration of the patch. The patch, when mounted on the skin, generates a transdermal ionic current with the osmotic flow from anode to cathode. I will present the results of two applications of the BFC patch. One is the transdermal dosing by the “through skin” current. The other is the wound healing by “on skin” current.
To improve delivery efficiency of skin patch, the iontophoresis induced by mild electric current (below 500 μA cm-2) has been used. The integration of a lightweight and safe power source would produce a more patient-compliant iontophoresis patch. Herein, we prove the BFC can drive iontophoresis, and realize totally disposable electric DDS patch.
Cells in the skin respond to electric current during a wound healing process. Taking advantage of this phenomenon, a stretchable bioelectric plaster is developed to generate ionic current along the surface of the skin by enzymatic electrochemical reactions. The bioelectric plaster fits to the skin and generates electric current above the wound for 12 hours to accelerate wound healing.
In addition to the above applications of BFC for generating iontophoretic flow, we have studied also the application of BFC for sensing medical information. I will present the results on the sensing of lactic acid in sweat and in interstitial fluid with the self-powered skin patches.
References: “Organic Transdermal Iontophoresis Patch with Built-in Biofuel Cell” Nishizawa et al., Advanced Healthcare Materials, 2015, 4, 506-510. “Accelerated Wound Healing on Skin by Electrical Stimulation with a Bioelectric Plaster” Nishizawa et al., Advanced Healthcare Materials, 2017, 6, 1700465-1700470.

Figure 1
Novel Pyrolyzed Carbon Processing for Advanced Microelectronic Applications
Authors: Finnegan Patrick Sean , Washburn Cody M , Dyck Christopher , Burckel D Bruce , Blecke Jill , Rector Michael N , Pfeifer Kent B. , Satches Michael R. 
Published: February 2020

Sandia National Laboratories has developed an ability to fabricate multilayered, all carbon MEMS devices, complete with future mixed material signal routing. Carbon is a durable and adaptable material, suitable for many microelectronics applications and can be micromachined from blanket films, enabling a production scalable fabrication process. Silicon based MEMS systems have dominated the market for 20+ years of development, with supplemental effort leveraging the IC industry. Carbon as a standalone material and silicon with carbon offer unique combinations of material properties which complement future design space for harsh environments [Figure 1]. It can withstand high temperatures, and can also be tuned for specific performance characteristics by incorporating nanoparticles, effectively manipulating resistivity, Young’s modulus and Poisson’s ratio. Carbon is highly conductive, inexpensive, and easy to produce.
Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA-0003525. The views expressed in the article do not necessarily represent the views of the U.S. Department of Energy or the United States Government.

Figure 1
Preparation and Polarization Behaviors of Novel Air Electrode Using Nickel-Coated Resin Particles
Authors: Okumura Takuya , Kawaguchi Kenji , Minami Kazuya , Minamiyama Hideaki , Morimitsu Masatsugu 
Published: February 2020

An air secondary battery using aqueous alkaline solutions is one of the promising candidates of next-generation energy storage devices, and the bi-functional air electrode for oxygen reduction during discharge and oxygen evolution during charge is the key component for a high energy density and a good cycling performance. The air electrode typically consists of carbon material, catalyst, and PTFE, in which carbon material is light and conductive, but not highly durable for oxygen evolution, so that alternative material with a higher durability is expected. In this work, we aimed to develop a novel air electrode using core-shell structure of resin particles, of which the surface is coated with nickel alloy film by electroless deposition, since this unique material is light and conductive with a high durability for alkaline solutions and oxygen evolution. This paper presents the preparation of the air electrode and the polarization behaviors for oxygen reduction and evolution.
Nickel alloy coated resin (NCR) particles used for the air electrode were prepared by electroless deposition of nickel-phosphorus alloy on the composite resin particles comprising silica and melamine resin. The NCR particles were mixed with Bi1.87Ru2O6.903 nano-partilces as the catalyst and PTFE partilces as the water repellent agent, and the mixture was pressed onto a nickel mesh to form a sheet by roll press at 80℃. For comparison, we prepared the air electrode consisting of NCR and PTFE partilces without the catalyst. Cyclic voltammetry was performed to measure the polarization of the air electrode which faced air on one side and 6 mol/L KOH solution on the other side in a three-electrode cell.
The air electrode using NCR was successfully prepared at the weight ratio of NCR : catalyst : PTFE = 58 : 29 :13 % by roll press at 0.5 MPa. The obtained electrode showed 46% weight reduction compared to that comprising nickel alloy coated silica (NCS) particles with the catalyst and PTFE in our previous study [1]. The polarization curves of the air electrodes with and without the catalyst indicated that oxygen reduction current was quite small at the air electrode without the catalyst, while the reduction current was seen at about 0 V vs. Hg/HgO reference electrode and increased at more negative potentials, indicating that NCR particles work well as the conducting material of the air electrode. In this paper, a comparison in polarization performance between the air electrodes using NCR, NCS, and graphite powders will be presented.
Reference
[1] H. Sano, M. Morimitsu, TMS 2017, San Diego (2017).
3D Printing of Smart Gels
Authors: Shiblee MD Nahin Islam , Ahmed Kumkum , Saito Azusa , Takamatsu Kyuichiro , Yoshida Kazunari , Khosla Ajit , Kawakami Masaru , Furukawa Hidemitsu 
Published: February 2020

Various kind of gel materials for example tough double network hydrogels [1], shape memory hydrogels [2] and ionic gels [3] have been developed with potential in numerous sectors. The transparent, flexible and low friction properties of these gels have added different prospects in scientific and technological areas. Utilization of 3D printing in fabrication of gel materials is still in its infancy and thus hindering rapid prototyping and design freedom. In this work, we have fabricated smart gels like thermos-responsive gels and conductive gels etc. using both customized optical gel 3D printers named SWIM-ER and commercial printer named Acculas. This process of 3D printing enabled rapid and moldless fabrication of smart gels with variety of 3D design from macro to micro scale. Robust thermos-responsive Poly (dimethyl acrylamide-co-stearyl acrylate and/or Lauryl Acrylate) (PDMMAm-co-SA and/or LA)-based shape memory gels (SMGs) with tunable mechanical, thermal, swelling, and optical properties are obtained by optimizing their critical conditions during 3d printing. The superior physiochemical properties of such smart gels widen the range of applications for soft robotics, biomedicine, flexible electronics, mimicking organ structure, bioinspired lens and sensing applications.
References

Gong, J. P., Katsuyama, Y., Kurokawa, T., Osada, Y., “Double-Network Hydrogels with Extremely High Mechanical Strength,” Adv. Mater., 15, 1155-1158 (2003).

Kabir, M.H., Ahmed, K. Furukawa, H., Microelectron. Eng. 150, 43–46 (2016).

Ahmed, K., Watanabe, Y., Higashihara, T. Arafune, H. Kamijo, T., Morinaga, T. Sato, T., Makino, M. Kawakami, M., Furukawa, H. Microsyst Technol 22, 17 (2016).
(Invited) Enzymatic Preparation of Supramolecular Hydrogels by Means of Amylosic Helical Assemblies
Authors: Kadokawa Jun-ichi 
Published: February 2020

Amylose, which is a helical polysaccharide and well-known as a component of starch, forms controlled assemblies, such as a double helix and inclusion complexes depending on whether guest compounds are present or not. Therefore, amylose has been employed as a functional polymeric material. However, little has been reported regarding the formation of inclusion complexes between amylose and polymeric compounds. The main difficulty in incorporating polymeric compounds into the amylose cavity is that the driving force for the binding is only caused by hydrophobic interactions. Amylose, therefore, does not have sufficient ability to include the long polymeric chains. The author has developed a new method of the polymerization system called “vine-twining polymerization” for the formation of well-defined polysaccharide supramolecules, that is, amylose–polymer inclusion complexes. The method was achieved by phosphorylase-catalyzed enzymatic polymerization of α-D-glucose 1-phosphate (G-1-P) monomer from malooligosaccharide primer to produce amylose, in the presence of hydrophobic synthetic guest polymers. The image of this polymerization system is the similar as the way that the vines of a plant grow twining around a rod. By means of this method using designed guest polymers, the author has prepared hierarchically controlled amylosic supramolecular network materials, which formed hydrogels in aqueous media.
For example, the author performed the preparation of supramolecular network hydrogels by the vine-twining polymerization using graft copolymers composed of hydrophobic graft guest polymers, such poly(γ-glutamic acid-graft-ε-caprolactone) (PGA-g-PCL). A supramolecular network hydrogel was obtained with the progress of the vine-twining polymerization, which showed a self-standing property. Macroscopic interfacial healing was achieved by the formation of inclusion complexes at interface between two hydrogel pieces through the enzymatic polymerization. A porous cryogel based on supramolecular network structure was obtained by lyophilization of a hydrogel. The XRD result of the lyophilized sample indicated the presence of inclusion complexes of amylose with the PCL graft-chains between intermolecular (PGA-g-PCL)s, which acted as supramolecular cross-linking points for the hydrogelation. Furthermore, ion gels were fabricated by soaking the hydrogels in an ionic liquid, 1-butyl-3-methylimidazolium chloride.