bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multi-Electrode Configurations for Electrochemical Measurements
Authors: Moss Eugene Newton , Nelson Ruben , Moss Pedro L. , Weatherspoon Mark H. 
Published: February 2020

Multiple electrodes for standard electrochemical measurements can provide appropriate results depending on the system. Two electrode measurements are common in such systems where the interactions between the anode and the cathode are of interest, such as in batteries. It is beneficial to understand the capability of three electrode measurements, since this configuration can provide accurate data on a single electrode of interest with respect to a third reference electrode in any system, like in aqueous solution.
The cyclic voltammetry (CV) measurements were performed by the Solartron 1287 at a scan rate of 50 mV/s on a system where a platinum metal counter electrode and a Teflon rod with a circular, planar glassy carbon surface working electrode were immersed in a solution of 0.5 M sodium sulfate (Na2SO4). The EIS measurements were performed by the VersaStat 4 potentiostat on an identical system.
The two electrode CV in Figure 1 show various potentials where anodic and cathodic peaks occur, indicating the presence of oxidation and reduction reactions [1]. The fact that there appears to be two peaks on the voltammogram at about -0.4 V during the forward scan and -0.5 V during the reverse scan suggests that this process is reversible or quasi-reversible [2].
For comparison, a third electrode, a silver/silver chloride (Ag/AgCl) reference electrode, is introduced to the system and a CV is performed, with the results shown in Figure 2. During the forward scan, the peak at -0.4 V in Figure 1 is hardly visible in the Figure 2 measurement, potentially indicating that there is no significant reaction at the working electrode, although it must be considered that the peak in Figure 1 is a much smaller current density scale. The -0.5 V peak on the reverse scan remains, albeit resulting in a different current density. Hence, a possible conclusion can be made in that a change in the rate of reaction at the working electrode is present.
The EIS measurements in Figure 3 show the comparison of the impedance of two different electrodes using a three electrode system. The impedance measurements were performed using the same electrode setup that was used in the three electrode CV measurements. As expected, the impedance of the carbon electrode was much greater than that of the platinum electrode across the spectrum, especially away from the high frequency end.

Acknowledgment

This work was supported by the FREEDM ERC program of the National Science Foundation under award number EEC-08212121.

References

1. Linden, David, and Thomas B. Reddy. Handbook of Batteries. New York: McGraw-Hill, 2002. Print
2. Jan C. Myland, Keith B. Oldham. Quasi-reversible Cyclic voltammetry of a surface confined redox system: a mathematical treatment. Ont. Canada. 2005
Chitosan-Based Polymer Electrolyte Containing an Ionic Liquid and Inorganic Salt
Authors: Chupp Jeremy , Shellikari Annadanesh , Chatterjee Jhunu 
Published: February 2020

Abstract:

Electrochemical energy storage systems (e.g. batteries and supercapacitors) have a vital role in the applications of many portable electronics, medical equipment, electric vehicles, military devices, and renewable energy [1]. The advancements in these technologies, increase the demand for electrochemical energy systems to achieve higher levels of performance [2]. The development of these high-performance systems have proven extremely difficult because of the need to simultaneously satisfy multiple battery performance requirements such as high energy, high power, long cycle life, low-cost, wide temperature range, safety, minimal impact to the environment, and flexibility to meet various design needs [3,4].
Currently, conventional electrochemical storage systems suffer from serious problems such as leakage, toxicity, and high-cost disposal, resulting in unsuitable long-term sustainability [1]. Solid polymer electrolytes have attracted considerable attention for their potential in electrochemical devices due to their light weight, thermal stability, reduced risk of leakage, and flexibility [4]. These systems are mainly comprised of a crosslinked network between a polymer, an organic liquid (e.g. ethylene carbonate, propylene carbonate, diethyl carbonate, etc.), and lithium based salt [5].
In this study, a gel electrolyte consisting of the host polymer, chitosan, has been synthesized to compare the crosslinking components, acetic acid and adipic acid. The films were incorporated with an ionic liquid and inorganic salt (LiCl) to increase ionic conductivity. FT-IR plots were compared to determine possible cross-linking mechanisms. Thermal analysis and AC impedeance data were obtained to determine the effect of the crosslinker, as well as the concentration of salt on the thermal stability and ionic conductivity of the gel samples.

References:

[1] N.K. Idris, N.A. Nik Aziz, M.S.M. Zambri, N.A. Zakaria, M.I.N. Isa, Ionic conductivity studies of chitosan-based polymer electrolytes doped with adipic acid. Springer Ionics 2009, 15:643-646
[2] (article in press, main paper I have been following, I couldn’t find it online) M. Yamagata, et. al., Chitosan-based electrolyte containing an ionic liquid for high-performance non-aqueous supercapacitors. Electrochim. Acta (2012)
[3] Edited by Claus Daniel, Jurgen O. Besenhard. Handbook of Battery Materials 2e. Wiley-VCH Verlag GmbH & Co. KGaG (2011)
[4] G P Pandey, Yogesh Kumar, S A Hashm, Ionic Liquid incorporated polymer electrolytes for supercapacitor application. Indian Journal of Chemistry (2012), 49:743-751
[5] Jhunu Chatterjee, Tao Liu, Ben Wang, Jim P. Zhang, Highly conductive PVA organogel electrolytes for applications of lithium batteries and electrochemical capacitors. Solid State Ionics (2010), 181:11-12:531-535
Enhanced Areal Capacitance of Solid-State Supercapacitors Based on Graphene Mixed Gel Electrolyte
Authors: Wang Jun-Yi , Liao Chiang-Sheng , Luo Yi-Hsiang , Huang Kuo-Yen , Huang Jin-Hua 
Published: February 2020

To meet the widely used portable and wearable electronic devices with improved funtionalities, developing flexible energy storage devices with larger energy density is an important issue. To this end, fabricating electrodes with materials that can act well while bending or twisting is necessary. Reduced graphene oxide is a promising candidate because of its outstanding mechanical and chemical properties, easily accessed surface area, and potential to be manufacturable [1]. In this research, we proposed a facile method to fabricate a graphene-based, flexible all solid-state supercapacitors. Briefly in fabrication, reduced graphene oxide (rGO) solution derived from modified Hummers method and hydrazine reduction [2] was directly drop cast on a flexible Au-coated polyimide substrate to form a porous electrode. Then the rGO solution mixed with PVA/H3PO4 was poured onto the electrode and air dried for 12 hours until solidified. Two as-made electrodes were pressed face to face to finish the device encapsulation.
SEM images of drop cast rGO electrode show a layered morphology with pores enable the gel electrolyte to inject in. The electrochemical characteristic of the as-made device is investigated by CV measurement. For the device using PVA/H3PO4 as electrolyte, only 41 mF/cm2
is obtained at the scan rate of 100 mV/s, whereas the device with rGO/PVA/H3PO4 as electrolyte shows 130 mF/cm2, about two times larger. We believe that a suitable mass ratio of rGO dispersed in the gel electrolyte forms a continuous 3D network that can contribute to electric double layer capacitance. The CV result shown in figure 2 comes from the sample using PVA/H3PO4 with 0.1 wt% rGO mixed. And the optimization of varied rGO mass ratio is investigated.
Reference
[1] M. Segal, Nat. Nanotechnol. 2009, 4, 611-613.
[2] D. Li, M. B. Muller, S. Gilje, R. B. Kaner, G. G. Wallace, Nat. Nanotechnol. 2008, 3, 101-105
Sige Selective Epitaxial Growth Process for 22 Nm Node CMOS and Beyond
Authors: Wang Guilei , Tianchun Ye , Luo Jun , Qin Changliang , Xu Yefeng , Chen Tao , Xu Qiang , Hong Peizhen , Yang Tao , Li Chunlong , Xu Gaobo , Yu Jiahan , Yin Haizhou , Li Junfeng , Yan Jiang , Zhu Huilong , Zhao Chao , Radamson Henry H 
Published: February 2020

As CMOS technology downscales into 22nm and beyond nodes, strain engineering technologies are widely used to improve the short channel effect and enhance MOS mobility to make high performance devices. During these technology developments, SiGe selective epitaxial growth has been used as stressor material in source and drain (S/D) region to induce uniaxial strain in channel region [1].
In order to further enhance the MOS channel mobility, the recess shape has to be designed to create maximum strain from the grown SiGe layers. To achieve this goal the etch step has been modified to elaborate a sigma (∑) shape recess and a high Ge content film is deposited in S/D regions [2]. Then SiGe epitaxy process becomes sensitive to surface quality of the recess where a careful etching and in- and ex-situ cleaning are demanded.
In this study, selective Si1-xGex growth (0.25≤x≤0.35) with boron concentration of 1-3×1020 cm-3for 22nm node CMOS process has been investigated (see Fig.1). The selectivity issue has examined/tuned around the gate region where both nitride and oxide layers were presented and the thermal budget was decreased to 800 °C to preserve the sigma shape in the S/D regions (see Fig.2).
The structures contained two Si1-xGex layers; where the recess was filled first with Si0.65Ge0.35 and then a cap Si0.75Ge0.25layer to elevate the S/D regions. The purpose for having the elevated SiGe cap layer was to avoid strain relaxation in the SiGe bottom layer during the Ni-silicidation process.
The Ge content in epi-layers on the chips was measured directly by rocking curves (RCs) using high-resolution x-ray diffraction (HRXRD). RC were done at (113) reflection where the incident beam is as low as 2.6° and a large area of sample containing an enormous of number of transistors could be covered by x-ray beam. These RCs were simulated by the Takagi-Taupin equations and compared to the experimental curves in order to obtain the high precision data analysis[3]. In these measurements, the boron concentration was estimated by the strain compensation in SiGe layers. The shift of B-doped SiGe peak was compared to the intrinsic ones and interpreted into the substitutional dopant concentration. In these SiGe layers, the B dopant concentration was quite high and the strain compensation could easily be measured.
Cross-section images where provided by high-resolution scanning electron microscopy (HRSEM) and transmission electron microscopy (HRTEM) to measure the layer thickness, epi-quality, and integrity of the whole transistor structures. In the latter analysis, energy dispersive spectroscopy (EDS) technique was also employed to measure the Ge profile in parallel and perpendicular directions in the S/D regions of the transistors.
Finfet Gate Etch Towards 16nm Node CMOS Technology
Authors: Hong Peizhen , Zhao Zhiguo , Li Chunlong , Meng Lingkuan , He Xiaobin , Han Jianghao , Lu Yihong , Xiong WenJuan , Zhang Yongkui , Yin Huaxiang , Zhu Huilong , Li Junfeng , Yan Jiang , Zhao Chao 
Published: February 2020

The 3D tri-gate FinFET device architecture is a key transistor scaling to 22nm node and beyond for its excellent short-channel performance[1]. However, compared with planar transistors, it poses greater challenge in the finFET gate etch.[2] As shown in fig.1, the etch needs to stop on top of the fin while etching further down to the STI oxide layer. Therefore, the top of fin needs to endure long time over etch without any structural damage which would adversely affect device performance. What’s more, the gate profile must be vertical and there should not be residual in the corner of gate and fin. It is not an easy task to achieve, at the same time, the three goals of vertical gate profile, no residual in the corner of fin and gate, as well as no structure damage on the top of fin, due to an unavoidable tradeoff. More specifically, vertical gate profile and no residual in the corner of fin demand strong etch function and light polymer, while no structure damage in the top of fin requires weak etch function and heavy polymer, which points to high etch selectivity of silicon to oxide layer.
To achieve good etch results, one often falls into this dilemma. As far as we know, few publicly available papers have provided satisfactory solutions to the above- mentioned problem. In this work, we deal with it.
The process of gate stack with CD below 30nm is illustrated in fig.2. Then, a HBr/O2 process in transformer coupled plasma is applied to finFET gate etch. As shown in fig.3, gate profile is vertical, fin is well protected and no residual appears in the corner fin.
In conclusion, an HBr/O2 plasma etch process of finFET gate with CD below 30nm is investigated.Through appropriate tradeoff , an etch result of vertical gate profile, no residual in the sidewall and corner of fin, no structure damage on the top of fin is achieved.
Interdigitated Nanoelectrode Arrays for Enhanced Sensitivity
Authors: Rohan James F. , Moore Michael , Barry Sean , Wahl Amelie , O' Riordan Alan 
Published: February 2020

Nanoelectrode arrays offer the potential for enhanced performance due to the improved mass transport characteristics offering the potential for faster and more sensitive electroanalysis. The inter-electrode distance can be tailored to optimise the electrochemical response depending upon the requirements.
Diffusion profiles for nanowire electrode arrays with various inter-electrode distances have shown that nanowires sufficiently spatially resolved and diffusionally independent in potential sweep experiments demonstrate superior electrochemical performance by comparison with nanowires that are relatively close to each other (overlapping diffusion profiles). Alternatively, arrays with diffusionally overlapping profiles exhibit enhanced performance (current amplification) when employing step voltammetric techniques such as square wave voltammetry. This has been attributed to operation in the generator-collector (GC) mode.
In this work we demonstrate that interdigitated gold nanowire arrays fabricated on silicon can also operate in the GC mode in simple potential sweep experiments. Collection efficiencies above 90% are achieved for the nanoelectrode designs employed. The use of nanowire arrays in the GC mode led to a 25 times current amplification over that for single nanowires thereby permitting significantly lower detection limits for electroanalysis.
Figure shows a CV of 2 mM FcCOOH in 10 mM PBS solution produced when the second side of the array is held at -0.15V (red), +0.45V (green), and +0.15V (purple).
Novel Carbon Based Electrochemical C-Reactive Protein Biosensor
Authors: Papa Henry , Chatterjee Jhunu 
Published: February 2020

Abstract:

C-Reactive Protein (CRP), found in blood serum has been proven to show a direct correlation to the inflammation of arteries and likelihood of myocardial infarction (MOI) and cardiovascular disease (CVD). Conventionally, CRP is quantified at a third-party laboratory using Enzyme-Linked Immunosorbent Assay (ELISA). A point-of-care, accurate, and cheaper diagnosis technique could allow for rapid CRP detection and reduce health care cost.
Biosensors have been fabricated in attempts to meet diagnoses requirements. Biosensors belong to a class of diagnostic devices that play a significant role in unique detection and measurement of various biomarkers. In order to obtain a CRP biosensor with the necessary sensitivity and selectivity, a nanohybride material with unique catalyst system has been proposed.
The nanohybride material integrates carbon nanotubes (CNT) and metallic nano-particle catalysts. The carbon based material has an enhanced surface area that allows for excellent electrochemical biosensor performance. Immobilization of a CRP reactive enzyme provides for the needed CRP selectivity. These engineered CNT based electrodes have shown excellent sensitivity and detection of CRP as low as 0.025 mg/L.
Synthesis of γ-WO3 By Reactive Spray Deposition Technology for NOx and H2 Sensing
Authors: Jain Rishabh , Liu Yixin , Wang Yang , Lei Yu , Maric Radenka 
Published: February 2020

Metal oxide semiconductors such as n-type WO3 has remarkable sensing properties for NOx, NH3, acetone, ethanol, H2 and O3. Sensor response (S) is a function of the conductivity of the WO3 film on interdigited Pt or Au electrodes in given by the following equation:
S = Canalyte/Cair -1
where Canalyte is the conductivity of the film in presence of testing analyte and Cair is the conductivity of the film in air.
The gas detection occurs because of the reaction on the WO3 surface in presence of these gases causing a change in electron concentration and hence fluctuation in electrical conductivity.
In this work Reactive Spray Deposition Technology (RSDT) has been employed as a single step flame based open atmosphere direct deposition process for synthesizing 5-10 nm WO3 particles of primarily γ phase. RSDT is able to synthesize some unique phases of WO3 nano particles by rapidly quenching the particles by a ring of cold air flowing at 28 L/min as soon as they are produced in the hot zone of the flame at temperature around 700 ˚C. The particles reside in the hot zone for 6 milli sec and are quenched immediately. This causes the formation of some very unique phases and incorporation of defects which are otherwise not stable at room temperature.
The RSDT process with optimization of conditions such as temperature of the flame, flow rate of quench air and residence time of the particles in flame is able to synthesize materials with different structures and varying concentration of dopants. The influence of crystal structures on sensing activities will be largely explored.
The structure and morphology of the WO3 films prepared by RSDT has been probed by XRD, Raman Spectroscopy, BET, mercury porosimetry, profilometry, scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). Fig 1 shows the WO3 nano particles synthesized by RSDT.
Fig 2 shows the sensors used for depositing WO3. The as-prepared WO3 sensors will be applied for the detection of NOx and H2 sensitivities in the range of 30-400 ˚C, and characteristics such as sensitivity, limit of detection, reproducibility, stability will be reported. The selectivity for the interfering analytes such as CO2, NO2, SO2 and humidity will also be investigated. Finally the sensing mechanism will be discussed.
Business Principles in Sensor Development and Commercialization
Authors: Carter Michael T , Stetter Joseph R , Stetter Edward F 
Published: February 2020

The overarching goal of sensor development is to provide information and knowledge that can be used beneficially in decision making for individual and societal well being. Additionally, businesses must be profitable in pursuit of this goal or they do not survive. Business development and commercialization of technology involves a set of unique and challenging circumstances and problems. We are familiar with the problems encountered in making basic research a success, but many of us have not been exposed to the practical concepts and issues involved in business development and successful technology commercialization. This presentation will address some of the basic ideas of business, as well as many of the issues that one encounters in taking a sensor technology from the lab to the market. We will explore markets and market fragmentation, the nature of demand, barriers to market entry, supply and distribution chains, competition, intellectual property protection, competitive advantage, the product lifecycle, market analysis and other concepts relevant to sensor development. Understanding these concepts is important for conceiving and executing a commercial strategy.
During these discussions, various sensors, customers and markets will be used as illustrative examples. In particular we will discuss new printed sensors developed at KWJ Engineering and introduced in 2013, where relevant to the discussion. We will examine how regulation, codes and standards drive sensor markets and opportunities and will discuss some key considerations when embarking on invention and practical development of new sensors. Everyone involved in basic or applied sensor R&D should understand the basic realities of marketplaces to have a clear vision of where and how their technology can be implemented in the world.
An Indirect Impedance Technique to Determine Reinforcing Steel Properties
Authors: Alexander Christopher , Chen Yu-Min , Orazem Mark E. 
Published: February 2020

Studies have shown that the application of an electric field to the surface of an electrolytic medium can indirectly polarize a metal within the solution.1,2,3,4 This technique can be applied to the study of reinforcing steel in concrete, and in this particular paper, to the study of post-tensioning steel in grouted cylinder tendons used in bridge construction. With the use of Electrochemical Impedance Spectroscopy, a ﬁnite-element model has been developed to solve for the frequency-dependent potential distribution through a cylindrical grout specimen containing one axially-located steel strand. Impedance simulations were performed at diﬀerent steel corrosion states while incorporating the kinetics at the current-injecting electrodes.
Following the procedure of Huang et al.5, the electrode kinetics are expressed as an oscillating current density as the summation of a charging and faradaic current. The grout is modeled as a uniform conductivity media and Laplace’s equation is used to solve for the potential distribution. The impedance is simulated over a range of frequencies as the potential difference between two reference electrodes divided by the current of the working electrode. The results are compared to experimental measurements throughout the hydration process.
The effectiveness of this method relies on the use of accurate representations of the steel surface impedance. Passive film models developed from rotating disk experiments in simulated pore solution are used to describe the steel boundary condition in the finite element model. The simulated results incorporating these models show a similar impedance response as the measured impedance of an aged cylinder put through a wetting and drying cycle.
Barring an accurate model, this technique has the potential to effectively determine the interface properties of the embedded steel from the overall response of the system.

References

J. Zhang, P. J. Monteiro, F.H. Morrison, “Noninvasive surface measurement of corrosion of reinforcing bar in concrete: Part I Experimental results”, ACI Materials Journal,
98 (2001) pg. 116-125.

M Keddam, X. R. Novoa, V. Vivier, “The concept of floating electrode for contact-less electrochemical measurements: Application to reinforcing steel-bar corrosion in concrete,” Corrosion Science,
51 (2009) pg. 1795-1801.

C. Andrade, I. Martnez, “Metal corrosion rate determination of diﬀerent solutions and reinforced concrete specimens by means of a noncontacting corrosion method,” Corrosion
66 (2010) pg. 056001-056001.

C. Andrade, J. Sanchez, I. Martinez, N. Rebolledo, Analogue circuit of the inductive polarization resistance,” Electrochimica Acta
56 (2011) pg. 1874-1880.

V. M. W. Huang, V. Vivier, M. E. Orazem, N. Pbre, B. Tribollet, “The apparent constant-phase-element behavior of a disk electrode with faradaic reactions a global and local impedance analysis,” Journal of the Electrochemical Society
154(2007) C99-C107.