bluuebunny/crossref_metadata_2025_split huggingface dataset:
Epitaxially Grown PtxIr100-X Alloys with Enhanced Properties for Ammonia Electro-Oxidation
Authors: Sacré Nicolas , Galipaud Jules , Garbarino Sébastien , Roué Lionel , Guay Daniel 
Published: February 2020

Ammonia is a highly toxic gas, a major environmental pollutant, and a potential fuel for fuel cells. Thus the electro-oxidation of NH3 has important applications in NH3 safety sensors, NH3 decontamination in wastewater, and power production. However, on most electrode surfaces, the electro-oxidation of NH3 is plagued with low surface reactivity and surface contamination by reaction intermediates.
The vast majority of studies on the NH3 oxidation reaction have been performed on Pt electrocatalysts, and Pt remains the electrocatalyst which shows the highest current density at the lowest overpotential for catalyzing the oxidation of NH3 to N2. On Pt, the oxidation of ammonia occurs predominantly on (100) terraces. However, to the best of our knowledge, the effect of strain in the outmost metal layers and hybridization of the Pt d-states with Ir atoms (ligand effect) on the electro-oxidation of NH3 have never been studied. Accordingly, we have investigated the epitaxial growth PtxIr100-x alloys model electrocatalysts that mimic single crystalline systems. This was achieved by deposition on MgO(100) via pulsed laser deposition.
It will be shown that Pt and Ir form a kinetically stable alloy and that the PtxIr100-x alloys grew with the desired PtIr(100)[010]//[010](100)MgO configuration over the whole composition range. Also, the XPS data show that a surface alloy is formed over the whole composition range.
Electrochemical measurements were performed in 0.5 M H2SO4 to highlight the preferential (100) surface orientation. Cyclic-voltametry and chrono-amperometry experiments in alkaline media were then carried out in presence of ammonia. They demonstrate the importance of the (100) surface structure for the electro-oxidation of ammonia compared to randomly oriented surface (polycrystalline sample). The presence of iridium decreases the surface poisoning at PtIr (100) alloys. Finally, it will be shown that surface poisoning can be further reduced using a simple cyclic-voltammetry procedure.
Screen-Printed Electrodes Modified with Multi-Walled Carbon Nanotubes for Cisplatin Detection
Authors: Materón Elsa María , Wong Ademar , Klein Stanlei Ivair , Sotomayor Maria del Pilar T 
Published: February 2020

A screen-printed electrode modified with multi-walled carbon nanotubes functionalized with carboxyl groups (MWCNT-COOH/SPE) in a 0.1 mol L-1 NaCl solution (pH 7) containing 800 μmol L-1 of sodium dodecyl sulfate (SDS) was used in the selective quantification of the widely used antitumor drug, cisplatin (Fig. 1). The MWCNT-COOH/SDS/SPCE sensor was characterized by cyclic voltammetry, and the differential pulse voltammetry was used for the detection and quantification of analyte, or evaluated in presence of other antitumor drugs, like carboplatin, oxaliplatin, doxorubicin and gemcitabine. For solutions of cisplatin, the electrochemical analysis showed a linear correlation coefficient of 0.9974 to cisplatin at concentrations between 1.45 × 10-5 and 1.0 × 10-4 mol L-1, a sensitivity of 4.5 × 104 (±1.0×103) μA L mol-1, and detection and quantification limits of 4.6 × 10-6 and 1.4 × 10-5 mol L-1, respectively. The reproducibility of the sensor response evaluated by the analysis of three replicates, indicated a RSD of 3.91%.
The excellent response of the MWCNT-COOH/SDS/SPE cisplatin sensor allowed it to be test in samples of human blood serum whose levels of added cisplatin had been monitored by the HPLC. The average error % (sensor/HPLC) of 0.95 indicates that the combined methodology of MWCNT-COOH modified SPCE and the addition of a surfactant such as dodecyl sulfate is a convenient alternative for the use of HPLC for cisplatin quantitative determination in biological samples.

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Tailoring Morphology of ZnO Nanostructures on Fabrics By Electrochemical Deposition for Gas Sensors
Authors: Lee Eunji , Park Hyejin , Chung Yoonsung , Lee Seokhee , Kim Dong-Joo 
Published: February 2020

With significant advancements in field of nanotechnology, people are more interested in implementing the nanotechnology into practical and portable devices such as flexible and wearable devices. Research is actively focused on utilizing flexible substrates instead of solid and rigid substrates while sustaining excellent material properties to realize commercialization. For wearable devices, functional materials such as semiconductors need to be built on fabrics and/or fibers. Among various semiconducting materials, ZnO is an excellent candidate for many applications because of their facile fabrication of nanostructure and structure-driven electronic and optical properties.
There are many methods to fabricate ZnO nanostructures, but solution synthesis can be the most simple and effective way to construct ZnO on wearable substrates. Various parameters in solution process such as precursors, temperature, and pH have been investigated to change ZnO nanostructure and to understand the growth mechanisms. However, solution process with electrical bias on the morphological evolution has been rarely investigated. In addition, realization of ZnO nanostructures on various fabrics still remains as a key challenge for wearable electronics.
Therefore, we designed and investigated a simple solution method to control the morphology of ZnO nanostructures by applying external voltage on copper coated polyester taffeta fabrics. In addition, types of ZnO precursors in solution and types of fabrics were systematically investigated to determine the bias-driven morphology. The use of external voltage promotes nucleation of ZnO nanorods without ZnO seed layer. With the increase of external voltage, ZnO nanorods became agglomerate structures. The degree of agglomerates varies depending on the types of fabrics. Such comparative study in substrate effects provide insight on the growth mechanism in electrochemical deposition. Gas sensing properties of various ZnO nanostructures on fabrics are compared in detail.

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Doping Poly(Acrylonitrile-co-Butadiene-co-Styrene) with Titanium Dioxide Nanoparticles to Create Novel Chemical Sensors
Authors: Skorski Matthew R , Fox Douglas M , Miller Abigail E 
Published: February 2020

Introduction
The use of 3D-printing in the United States has skyrocketed in recent years. This has opened up the possibilities for cheap, reproducible, and modifiable chemical sensors that can be made in the lab. However, new polymers have to be developed that support these functions. To that end, this study will investigate the conductive properties of titanium dioxide (TiO2) nanoparticles suspended in Poly(Acrylonitrile-co-Butadiene-co-Styrene) (ABS). It is desired that the doped polymer be able to create 3D printed objects that can effectively conduct electricity. The applications for this technology would include 3D-printed chemical sensors, circuits, and other devices.
To study the mechanical strength and electrochemical effects of the TiO2, doped polymers are created for printing in 1,5, and 10 % by mass nanoparticle to ABS concentrations. The printed objects made from TiO2 doped ABS filaments will be compared to those objects made from store bought ABS filament.
Experimental
To create the doped polymer, ABS is mixed with the TiO2 nanoparticles in 10 mL of acetone per gram of doped polymer. After evaporation of the acetone the polymer is mixed in a DSM Xplore Micro 15cc Twin Screw Compounder before being molded into 3D printer filament with a Filabot Wee extruder. The 3D objects are printed with a FlashForge Creator. A MARK-10 advanced digital force gauge and an ESM301 motorized test stands are used to perform three point flexural tests and stress-strain tests. The electrochemical properties will be analyzed by using a Van der Pauw resistivity test.
Results and Discussion
Early work has shown that the ABS is able to suspend and disperse the TiO2 nanoparticles. While the Van der Pauw tests have not begun, preliminary mechanical testing has been completed. The mean and standard deviation for the stress and strain measurements of the 1% printed objects were 28.1 ± 9.5 MPa and 12.8 ± 4.4 %. The 5 % and 10 % graphs qualitatively showed similar large deviations for both values. The large standard deviation for both values is believed to be caused by the variation in the filament thickness. The filaments are expected to be 1.75 mm but were thinner along parts of the strand by up to 24%. When the tests were repeated with the filament diameters accounted for, the mean and standard deviation for the stress and strain measurements of the 1% printed objects were 39.4 ± 0.8 MPa and 8.93 ± 0.3 % (Figure 1). All future 3D prints will take the changing filament diameter into consideration.

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The Relationship Between Carbon Nanotube Surface Status and Electrocatalytic Performance Toward Oxygen Reduction Reaction of Cobalt Phthalocyanine /Carbon Nanotube
Authors: Zhang Zhengping , Wang Feng , Ji Jing , Liu Jingjun , Li Zhilin 
Published: February 2020

Recently, noble metals and their alloys nanoparticles supported on the carbon materials as carbon-based composite electrocatalysts are widely studied. However, on one hand, the high cost associated to these noble metals is still a drawback for full commercial application; on the other hand, their designing is limited by their characteristic. It is important to develop a new catalyst with low cost, high catalytic activity and wide designing for oxygen reduction reaction. Cobalt Phthalocyanine (CoPc) has high catalytic activity, and its special macrocyclic structure can perform well with the carbon materials toward Oxygen Reduction Reaction (ORR). Thus, the design of relationship between CoPc and its carbon-base is a necessary mission for this new catalyst for ORR.
This abstract mainly focused on the different surface treatment of carbon nanotubes (CNTs) connect to CoPc and their electrocatalytic performance for the ORR process. Investigating raw CNTs, acidification CNTs (AF-CNTs) and activation CNTs gives us three different surface treatment CNTs coated by CoPc, which have higher electrocatalytic performance than CoPc itself. Here we find CoPc /AF-CNTs exhibit highest catalytic activity, and the Tafel Polarization curve test showed that CoPc/AF-MWCNTs perform the highest exchange current density (i0) in oxygen reduction reaction, and even its reaction rate is faster than commercial catalyst. The results indicated that the broken CNTs surface is beneficial for coating CoPc, as well as the charge transformation during the catalytic process. At the same time oxygen- containing groups on carbon-base can promote catalytic activity of CoPc for the ORR process.

Figure 1
Investigation of Lithium-Ion Diffusion and Irreversible Processes in Dual-Ion Cell
Authors: Balabajew Marco , Kranz Tobias , Roling Bernhard 
Published: February 2020

In 2012 Placke et al. proposed so called „dual-ion cells“ as a new type of energy storage system. They reported an extraordinary cycling stability with a capacity retention of more than 99% after 500 cycles. Even though the achievable cell voltage in this kind of cells is about 4.6 V, the specific energy is still quite low compared to common lithium-ion batteries. The reason for this is a fundamental difference from conventional lithium-ion batteries, since not only the electrodes, but also the electrolyte acts as active material. During charging, lithium cations are reduced and deposited at a metallic lithium anode, while the anions are intercalated into graphite. During discharging, anions and cations are released back into the electrolyte (see figure 1).[1] Therefore the electrolyte acts as ion source, and the concentration hereby limits the energy density.
As the cell voltage of “dual-ion cells” is very high the electrolyte needs to have a wide electrochemical window. For this reason, typically ionic liquid based electrolytes are used for this application. However, the concentration of lithium salts in ionic liquids is strongly limited due to solubility, increasing viscosity and decreasing conductivity.[2] During cycling the concentration underlies changes due to the extraction of lithium salt. This fact gives the possibility to investigate fundamental processes during charging and discharging by measuring the electrolyte resistance. In this work we therefore use electrochemical impedance spectroscopy in 2- and 3-electrode setup to gather information about diffusion processes in the electrolyte and about the reversibility of the processes during charging and discharging.
Figure 1: Functionality of a dual-ion cell (derived from [1]).
[1] T. Placke, P. Bieker, S. F. Lux, O. Fromm, H.-W. Meyer, S. Passerini, M. Winter, Zeitschrift für Physikalische Chemie, 226, 391 (2012).
[2] T. Frömling, M. Kunze, M. Schönhoff, J. Sundermeyer, B. Roling, Journal of Physical Chemistry B, 112, 12985 (2008).

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Device Simulation of Hydrogen-Terminated Diamond Mosfet and Extraction of Small-Signal Parameters
Authors: Zhou XI , Albin Sacharia 
Published: February 2020

Diamond has exceptional properties suitable for electronic and photonic devices. In particular, hydrogen-terminated diamond (HTD) FET devices have been studied recently for potential radio-frequency (RF) applications by exploiting its high conductivity at diamond surface, high thermal conductivity and simple fabrication process [1-3]. However, the device simulation of such FET device is rarely reported because the surface conductive mechanism is not fully understood.
In this work, a new device structure including a surface adsorbate layer (ADL) is presented and a possible explanation of the formation of surface conductive layer is provided. Based on our theory, the 2D device simulation is achieved using Sentaurus Technology Computer-Aided Design software; both the capacitance-voltage (C-V) and DC current-voltage (I-V) properties of the HTD MOSFET can be understood well. It is found that the current mainly flow at diamond surface when the drain-source voltage (VDS) is small but meander into the bulk when |VDS| becomes larger. The working mode of the device can change from enhancement to depletion as the gate length (Lg) shrinks, and the threshold voltage becomes very sensitive to Lg when Lg≤0.2μm. The off-state leakage current increases drastically when Lg is approaching 50nm, causing the on/off current ratio dropping from 106 to 103.
In addition, the radio-frequency (RF) small-signal equivalent circuit of the device is generated and the frequency responses of the circuit components are studied. For devices with small gate length (<0.2μm), the non-quasi-static (NQS) effect happens at the frequency over 10GHz, making the HTD device suitable for applications in microwave range. The simulated transition frequency fT is around 170GHz when Lg=50nm, but it is greatly affected by the source/drain series resistance. Finally, a strategy is presented to extract the values of circuit components from simulated two-port parameters, which works well up to 2GHz.
[1] M. Schwitters, M. P. Dixon, A. Tajani, D. J. Twitchen, J. I. S. E. Coe, H. El-Haji et al., Diamond-MESFETs-synthesis and integration, IEEE European Radar Conference, (2005) pp.1-4.
[2] M. Kasu, K. Ueda, H. Ye, Y. Yamauchi, S. Sasaki, T. Makimoto, High RF output power for H-terminated diamond FETs, Diamond and Related Materials, 15(2006) pp.783-786.
[3] J. L. Liu, C. M. Li, R. H. Zhu, J. C. Guo, L. X. Chen, J. J. Wei et al., RF characteristic of MESFET on H-terminated DC arc jet CVD diamond film, Applied Surface Science, 284 (2013) pp.798-803.
Room Temperature Processed Electrochromic Smart Windows with Flexible Film
Authors: Lee Sohee , Kim Haekyoung 
Published: February 2020

Electrochromic (EC) devices, which dynamically change color under applied potential, are widely studied for use in energy-efficient smart windows. To improve the viability of smart windows, many researchers are utilizing nanomaterial, which can provide electrochromic devices with improved coloration efficiencies, faster switching times, longer cycle lives, and potentially reduced costs. We report the synthesis of nanomaterials for transparent conducting electrodes (TCE). The smart window characteristics were measured and studied.
For fabrication of smart window, WO3 ink was spin-coated on ITO/glass and electrolyte of ethylene carbonate, dimethyl carbonate, and lithium perchlorate was used. The counter TCE was fabricated by bar coating method with silver nanowires (Ag NW) on PET film, which has 25 ohm/sq of sheet resistance and 90% of transmittance. EC device with Ag NW TCE was assembled and sealed with epoxy. The performances of smart window were characterized with the performance of Ag NW TCE. The potential range for coloring was 1.5 – 2.5 V and the transmittance was 87 %. The bleaching was observed at -2.5 V and the transmittance was below 40 %. The flexible TCE can be applied flexible and bendable smart window with low process cost.
Synthesis of Ruthenium Complexes for Semiconductor Device Using Atomic Layer Deposition
Authors: Jung Eun Ae , Han Jeong Hwan , Park Bo Keun , Kim Chang Gyoun , Son Seung Uk , Chung Taek-Mo 
Published: February 2020

Ruthenium (Ru) has attractive material properties due to its promising characteristics such as a low resistivity (7.1 μΩ·cm in the bulk), a high work function (4.7 eV), and feasibility for the dry etch process. These properties make Ru films appropriate for various applications in the state-of-art semiconductor device technologies. Thus, it has been widely investigated as an electrode for capacitor in the dynamic random access memory (DRAM), a metal gate for metal-oxide semiconductor field effect transistor (MOSFET), and a seed layer for Cu metallization. Due to the continuous shrinkage of microelectronic devices, better deposition processes for Ru thin films are critically required with excellent step coverages in high aspect ratio (AR) structures. In these respects, atomic layer deposition (ALD) is a viable solution for preparing Ru thin films because it enables atomic-scale control of the film thickness with excellent conformality.
A recent investigation reported that the nucleation of ALD-Ru film was enhanced considerably by using a zero-valent metallorganic precursor, compared to the utilization of precursors with higher metal valences.
In this presentation study, we will display our research results on the synthesis and characterization of novel ruthenium complexes. The ruthenium compounds were easy synthesized by the reaction of ruthenium halide with appropriate organic ligands in protic solvent, and characterized by NMR, elemental analysis and thermogravimetric analysis.
ALD of Ru film was demonstrated using the new (zero-valent) Ru metallorganic precursor and O2 as the Ru source and reactant, respectively, at the deposition temperatures of 300-350oC. Self-limited reaction behavior was observed as increasing Ru precursor and O2 pulse time, suggesting that newly developed Ru precursor is applicable for ALD process. Detailed discussions on the chemical and structural properties of Ru thin films as well as its growth behavior using new Ru precursor will be also presented.
Cation Intercalation and High Volumetric Capacitance of Two-Dimensional Titanium Carbide
Authors: Lukatskaya Maria R. , Ghidiu Michael , Mashtalir Olha , Ren Chang E. , Zhao Meng-Qiang , Dall'Agnese Yohan , Barsoum Michel W. , Gogotsi Yury 
Published: February 2020

We recently produced a new 2-D material, viz. Ti3C2, by selectively etching aluminium from a MAX phase Ti3AlC2 and labelled it MXene. MXenes represents a large family of transition metal carbides and carbonitrides, not just a single phase. MXenes allow a variety of chemical compositions and are establishing themselves as a new class of two-dimensional materials. MXenes possess good in-plane conductivity, which in combination with their rich surface chemistry makes them attractive for electrical energy storage applications. However their use in electrochemical capacitors was only recently demonstrated (Lukatskaya et.al, Science, 2013).
Here, we report on the intercalation of Li+, Na+, Mg2+, K+, NH4
+, and Al3+ ions between the 2D Ti3C2Tx layers. In most cases, the cations intercalated spontaneously. The intercalation of some ions, notably Al3+, can be promoted electrochemically. We also report on intercalation-induced high capacitance of >300 Farads per cubic centimeter (much higher than that of porous carbons) of flexible Ti3C2Tx paper electrodes in aqueous electrolytes. Material showed no degradation of the capacitive properties after more than 10,000 cycles. Several different electrochemical techniques were employed to understand the mechanism of charge storage, such as in-situ spectroscopy, X-ray diffraction and other techniques.
Cyclic Voltammetric Studies of Nitroimidazoles in Aqueous Solution with Additions of Cysteine
Authors: Darzi Ghazwan M , Smith Diane K. 
Published: February 2020

Nitroimidazoles are antibiotics used to treat many infections by killing the bacteria that causes the infection. For example, metronidazole is a drug that belongs to the class of nitroimidazole antibiotics, and it is used to treat bacterial and protozoal infections. Nitroimidazoles need to be activated by a reduction reaction. Although it has been believed that the active form of this drug was the radical anion, there is increasing evidence which suggests that further reduced forms, such as the nitroso and hydroxylamine, are the active forms of this drug. Both species are known to react with cysteine and this may lead to cell death either by deactivation of key proteins or upsetting the redox balance in the cell.
Because of the high reactivity of the nitroso and hydroxylamine imidazoles, it is not generally possible to prepare and isolate them to study their reactivity directly. However they can be studied indirectly using cyclic voltammetry since upon reduction of the nitro group in aqueous solution new peaks due to the oxidation of the hydroxylamine and reduction of the nitroso can be seen. By varying the scan rate, information on the stability of these species in aqueous solution can be obtained. Further information on the activity of the nitroso and hydroxylamine forms can be obtained by adding equivalents of cysteine to the cell in order to monitor the rate of reaction between cysteine and the nitroso and hydroxylamine forms of different imidazoles.
This paper will describe the cyclic voltammetry of 1-methyl-5-nitroimidazole and 1-methyl-2-nitroimidazole in aqueous solution in greater detail. Rough estimates of the lifetimes of nitroso and hydroxylamine derivatives in water will be determined using the current vs. time data at different scan rates. If possible, better estimates of the lifetimes and the rates of reaction with cysteine will be obtained by simulation of the voltammograms.