bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of Electrolyte Chemistry and Solvation on Interphasial Ion Dynamics for Low-Temperature Li Metal Batteries
Authors: Holoubek John , Baskin Artem , Liu Haodong , Kim Kangwoon , Yin Yijie , Wu Zhaohui , Lawson John , Pascal Tod A. , Liu Ping , Chen Zheng
Published: November 2022

The influence of electrolyte chemistry on the ion-desolvation process of charge-transfer in Li-based batteries is a crucial, yet murky aspect of their design and operation. This desolvation process has been shown to be a dominant factor for the low-temperature operation of batteries, where high energy density is necessary, but difficult to achieve. We have applied Li metal batteries in an attempt to provide such metrics, which show extremely disparate performance depending on the electrolyte applied in each cell. Specifically, we have found that the induction of ion-pairing and the inclusion of weakly-bound solvents results in a substantial improvement in both the reversibility and shorting behavior when plating Li at low-temperature, despite significant loss in the bulk ionic conductivity of the solution. To provide a deeper understanding of these experimental observations, we also apply free-energy sampling techniques at 298 and 213 K to simulations involving diethyl ether (DEE) and 1,3-dioxoloane/1,2-dimethoxyethane (DOL/DME) electrolytes, which display bulk solvation structures dominated by ion-pairing and solvent coordination, respectively. We find that the degree of ion-pairing in the electrolyte bulk and at the interphase plays a vital role in assisting the delivery of Li+ to the inner Helmholtz layer, and that the sterics of DME are prone to Li+ over-coordination in solution. This mechanistic reliance of ion-pairing at the interphase conflicts with the preferred solvent-dominated structure of the DOL/DME system, which is further emphasized at 213 K, where simulations predict that the balance between solvent and anion coordination is shifted significantly in favor of solvent. This work endeavors to provide unambiguous evidence of the importance of the solvation structure for interphasial charge-transfer kinetics as well as a mechanistic understanding of the phenomena at the interphase.

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(Invited) In Situ Electrochemical Raman Spectroscopy for Nanoscale to Macroscale Electrochemical Processes
Authors: Ren Bin
Published: November 2022

Raman spectroscopy has been increasingly applied in studying the electrochemical processes, including adsorption and reaction, under in situ or operando condition, because Raman spectroscopy can conveniently work in aqueous solution and provide fingerprint molecular information. In this talk, I will present the recent work in my group on developing various electrochemical Raman spectroscopy for in-situ and operando studies of electrochemical systems at the limits of time and spatial resolution and sensitivity

With the help of the plasmonic enhancement at the tip of a plasmonic material, electrochemical tip-enhanced Raman spectroscopy (EC-TERS) offers itself as the only nanospectroscopy for investigating the electrochemical interface with unprecedent spatial resolution and explicit chemical fingerprint information. We developed the electrochemical TERS both based on STM and AFM using the water immersion objective and homemade optical instrument. EC-TERS was applied to obtain the molecular fingerprint information of surface adsorption and electrochemical reaction on single crystal surfaces and monitor the plasmon-driven reaction at the nanoscale.

Aiming at addressing the challenge of monitoring the highly dynamic changing electrochemical interfaces under potential control and presence of the electrolyte, a transient electrochemical surface-enhanced Raman spectroscopy (TEC-SERS) was developed to monitor the structural evolution of surface species at a time resolution that equals the transient electrochemical methods (e.g. cyclic voltammetry and chronoamperometry), allowing the precise correlation of Raman signal with the molecular signature information and the electrochemical current signal. He observed an interesting two-step reaction processes that are impossible to observe by conventional steady state SERS methods. A wide-field Raman imaging system was developed to offer a high imaging speed to monitor the spatial and temporal change at every point over the whole electrode surface simultaneously. The heterogeneity of electrocatalytic reaction on the electrode surface was observed. This technique offers the possibility to spatially correlate electrochemical behavior and the particular surface sites where the reaction happens.
Oxidation of Aqueous H3PO3 on Pt Studied By X-Ray Spectroscopies
Authors: Wibowo Enggar , Garcia-Diez Raul , Bystron Tomas , Prokop Martin , van der Merwe Marianne , Arce Mauricio D. , Jiménez Catalina Elena , Efimenko Anna , Favaro Marco , Starr David , Gaupp Andreas , Wilks Regan George , Bouzek Karel , Bär Marcus
Published: November 2022

High-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs) employing a phosphoric acid H3PO4-doped membrane are considered to be promising sustainable electrochemical energy storage. The high-temperature operation has several advantages, such as a higher tolerance to CO poisoning, allowing coupling of HT-PEMFCs with reformers [1-3], as well the possibility for heat and electric energy co-generation [1,2]. However, during operation, phosphorus oxo-acids (e.g.: H3PO3) are generated on the anode. These impurities adsorb on the Pt catalyst [4-6], thus possibly negatively affecting the HT-PEMFCs performance. A detailed understanding of the H3PO3-catalyst (Pt) interaction is hence necessary for further HT-PEMFC optimization. However, besides an investigation of the H3PO3 adsorption behavior on Pt [6,7], literature on the behavior of the H3PO3 in contact with Pt (with/without polarization) is scarce.

In this work, the oxidation mechanism of H3PO3 was investigated using a combination of in situ x-ray spectroscopy techniques that directly probe the H3PO3/Pt interface interaction, complemented by ex situ x-ray photoelectron spectroscopy (XPS) and ion-exchange chromatography (IEC). IEC gave insights into the effect of Pt on the stability of deaerated aqueous H3PO3 solutions. XPS was conducted on H3PO3/support structures (including Au and Pt supports) to determine to what extent the support affects the H3PO3 oxidation. Furthermore, in-situ dip and pull near-ambient pressure (NAP-)XPS was conducted to investigate the state of H3PO3 at the H3PO3/Pt interface and in solution bulk. It was observed that at the H3PO3/Pt interface, H3PO3 was chemically oxidized to H3PO4, while in the bulk solution it remains stable, as shown in Figure 1. Moreover, in situ x-ray absorption spectroscopy at the P K-edge was conducted at different concentrations of H3PO3 in aqueous solutions (i.e., different amounts of H2O) in contact with Pt, to determine the role of H2O in the oxidation of H3PO3. A higher degree of oxidation was observed for the less concentrated H3PO3, implying that H2O participates in the oxidation mechanism of H3PO3 to H3PO4.

References:

[1] Chandan et al., A.. J. Power Sources 2013, 231, 264–278. [2] Asensio, et al. Chem. Soc. Rev. 2010, 39 (8), 3210. [3] Q. Li et al, J. Electrochem. Soc. 2003, 150 (12), A1599. [4] Sugishima et al, J. Electrochem. Soc. 1994, 141 (12), 3332. [5] Doh et al. ChemElectroChem. 2014, 1 (1), 180–186. [6] Prokop et al, Electrochimica Acta 2015, 160, 214–218. [7] Prokop et al, Electrochimica Acta 2016, 212, 465–472.

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Insights into Electrocatalytic Surface Chemistry Via Operando Spectroscopy, Spectrometry and Stress Measurements
Authors: Raciti David , Tackett Brian , Hight Walker Angela , Stafford Gery , Moffat Thomas P
Published: November 2022

On the verge of harnessing CO2 as a building block for carbon-based fuels, electrocatalysis stands uniquely poised to revolutionize the chemical industry through renewable electrification. For this vision to become reality operando measurement techniques must be applied to study phenomena at the electrode-electrolyte interface. Understanding the dynamic interaction between ionic species in the electrolyte, active sites and intermediates is paramount for the systematic advancement in chemical reactivity, durability, and selectivity required to become commercially relevant. I will demonstrate a suite of operando techniques, such as shell-isolated nanoparticle enhanced Raman spectroscopy (Figure 1a), mass spectrometry (Figure 1a), and cantilever curvature measurements (Figure 1b), that enable direct measurement of adsorbates, phase state and stress dynamics, respectively, at the electrode interface. The combination of results from these measurements enables quantification of sub-monolayer coverages of surfaces species as well as coverage vs stress relationships providing the capability to effectively tune properties of the electrode surface. Complimentary use of these techniques to comprehensively study chemical reactions at heterogeneous interfaces provides new insights into atomic events critical for sustainable electrification to be realized.

Figure Caption: (a) Identification of surface hydride on Cu(111) via complementary operando Raman and online mass spectrometry measurements and (b) cantilever curvature measurements combined with DFT calculations reveal the mechanism behind compressive stress due to CO adsorption.

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Quantitative Assessment of Structure Reactivity Correlation on Rapid Kinetics of Halogenated Aromatic Compounds: A Hydrodynamic Voltammetry Study
Authors: Pulikkal Ajmal Koya , Chhakchhuak Lalduhawma
Published: November 2022

Halogenations are mostly rapid and cannot be studied by the conventional method, hence, hydrodynamic voltammetry which is based on voltammetric principles can be adopted to study these fast reactions, provided either a reactant or a product in the reaction is electro reducible. These reactions are mostly electrophillic substitution reactions and second order when molecular halogens are used as a reagent. Rapid kinetic studies on some important halogenated aromatic compounds at rotating platinum electrode (RPE) using hydrodynamic voltammetry are summarized and reviewed for a period of the last few years. The advancement made to the technique as well as its application for mechanistic purposes, electrode kinetic measurements, pharmaceutical, and analytical applications have been addressed. As an investigative tool, kinetics has been used to obtain thermodynamic data that allows a quantitative comparison of the reactivity of the two substrates such as activation energy, velocity constants, frequency factors, and entropy change. This aids in configuring the mechanistic route, from among those theoretically possible by checking the compatibility with experimentally observed facts.
(Digital Presentation) Synergistic Effect of Sn and Cu Oxides for the Electrochemical Reduction of CO2 to Formic Acid
Authors: Kharel Pom , Hoque Md Ariful , Abad Keemia , Gnanamani M.K. , Liu Kunlei , Omosebi Ayokunle , Thompson Jesse
Published: November 2022

The development of an electrochemical catalyst system that converts carbon dioxide (CO2) to high-value chemicals, such as formic acid (FA) will simultaneously curb CO2 emissions to atmosphere and provide sustainable pathways to create a range of fuels at lower cost. Electrochemical conversion of CO2 to FA is a two-electron reduction process and can be carried out at ambient conditions, and the reduced product has been found wide-ranging applications in chemical industries for production of household products, and a safe liquid-phase chemical for hydrogen storage. Synergistic bimetallic electrocatalysts can improve the activity and selectivity over their monometallic counterparts by tuning the structure, morphology, and composition. At the University of Kentucky’s Institute for Decarbonization and Energy Advancement (UK IDEA), our enhanced bimetallic oxide carbon utilization (EBOCU) process uses an engineered catalyst that facilitates operating at relatively low applied potentials, and high product selectivity to produce FA. Using bimetallic tin-copper oxide containing 95 mol% of Sn and 5 mol% of Cu immobilized on mesoporous carbon xerogel and alkaline electrolyte, we observed that hydrogen evolution reaction is suppressed and the selectivity towards formate is enhanced for the cell potential from 3.6 V through 4.0 V. Notably, our electrochemical reactor is successful in converting CO2 to formate at the rate of 2 mM/h in 3 mL/min flow system. Maximum faradaic efficiency of 94% is achieved towards formate at 3.8 V, which remained above 80% even after 200 h of continuous operation.
(Digital Presentation) Electrocatalytic CO2 Reduction to Formic Acid: Kinetics and Equilibrium Modeling for the Downstream Separation of Formic Acid with Anion Exchange Resins
Authors: Hoque Md Ariful , Abad Keemia , Kharel Pom , Omosebi Ayokunle , Liu Kunlei , Thompson Jesse
Published: November 2022

Electrocatalytic carbon dioxide reduction reaction (CO2RR) technology can simultaneously minimize the CO2 concentration in the atmosphere and generate useful chemicals and fuels. Liquid formic acid (FA) produced from CO2RR is a chemical feedstock for industrial purposes as well as a potential hydrogen storage medium. The downstream separation of liquid FA from the CO2RR effluent increases the total costs in addition to the electrolysis and can also affect the environment adversely. Therefore, efficient, low-cost, and environmentally benign technologies for FA separation from the CO2RR are important for life cycle analysis and techno-economic analysis for this technology. Ion exchange has been proven as an advanced process for FA separation from aqueous solution. This method has attractive due to its high selectivity, low cost, ease of operation and recovery, availability to integrate with other systems, and environmentally benign nature.

In this work, three anion exchange resins: Ambersep 900 hydroxide, Amberlite IRA-96 free base, and Amberlite IRA-910 chloride forms have been tested to separate FA from the aqueous solution under varying resin loading (10-60 mg/mL) and initial FA concentration (0.05-0.50 M). The effect of potassium bicarbonate, a commonly used catholyte in electrochemical CO2RR on equilibrium FA adsorption capacity has been investigated with resin loading of 10 and 60 mg/mL under similar initial FA concentrations.

Kinetics and equilibrium studies data for the FA adsorption on three resins are interpreted using several kinetics and isotherm models. The kinetics data fits better with pseudo first order at high initial FA concentration and pseudo second order at low initial FA concentration. The results show that the Ambersep 900 hydroxide form with adsorption capacity of 430.8 mg of FA per g of resin is more efficient than the Amberlite IRA-96 free base form (369.9 mg/g) and Amberlite IRA-910 chloride form (291.2 mg/g) in the absence of potassium bicarbonate in the range of parameters studied. However, Amberlite IRA-96 (153.4 mg/g) and Amberlite IRA-910 (143.4 mg/g) can separate FA more efficiently from the potassium bicarbonate aqueous solution than the Ambersep 900 (94.1 mg/g). The experimental data for all resins can be well explained with the Freundlich isotherm model. In the presence of potassium bicarbonate, competitive adsorption of bicarbonate and formic acid reduces the FA adsorption capacity of resins. Experimental and modeling results will be discussed.
Electrochemical Sensing Platform for the Detection of Pesticides and GMO Protein in Food Matrices
Authors: Poudyal Durgasha , Dhamu Vikram Narayanan , Muthukumar Sriram , Prasad Shalini
Published: November 2022

The growing technology and development in the agriculture industry has led to the introduction of genetically modified organisms (GMO’s) crops having which have high resistance to insecticides, thus there is a tremendous rise in the use of the pesticides/insecticide worldwide. The underlying concern is about the possible health issue related to their residues in the daily dietary intake viz sources such as water, fruits, vegetables and grains. Therefore, various regulatory bodies have set the maximum residue limits for safe use of these pesticides or insecticides in agriculture land. Secondly, regardless of the rising debate or controversies about the GMO’s among society and producer, their cultivation is constantly increasing. As the impact of cultivating these crops on human health are under study, more than 50 countries have mandated the labelling of these GMO’s proteins to ensure the right to information to the consumers. Although these pesticides/insecticides and GMO’s can be detected precisely using gold standard analytical methods in the food matrix, but these methods require an expert to handle, and stringent sample pre-processing steps. Thus, there is a high demand for the portable, on-field device which can be used at the consumer levels requiring no pre-sample processing steps. In our work, we explore the use of the electrochemical assay method to detect the pesticides such as Chlorpyrifos, Glyphosate and GMO proteins in high fat and low-fat food matrices. The assay-based electrochemical multiplex sensor has been developed by modifying the screen-printed Au-electrode/carbon electrode substrate with the respective antibody at optimized concentrations. The real low-fat and high-fat sample matrices has been prepared by simply blending the mix using home blender. The real sample matrix spiked with the pesticides /GMO protein were tested for calibrated dose response from 0.3 ng/mL- 243 ng/mL, and the limit of detection of less than < 10 ng/mL were observed using this developed electrochemical portable device method. Such portable electrochemical device approach could be a promising on-field sensing tool for the pesticide and GMO protein detection.

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New Strategies for the Improvement of EC-SERS Effect in Organic Solvents
Authors: Fanjul Pablo , Ibáñez David , González-García María Begoña , Hernández-Santos David
Published: November 2022

Over the last years, combination of electrochemistry (EC) and surface-enhanced Raman scattering (SERS) has received growing attention due to the powerful features associated with EC-SERS effect. In particular, electrochemical activation of metal electrodes allows the generation of SERS substrates which provides the enhancement of Raman intensity in a single experiment. Although effective electrochemical methods have been developed [1,2], they are traditionally limited to aqueous solutions. Raman spectroelectrochemistry in organic media is an interesting alternative, but the development of new EC-SERS procedures is still required.

In this work, different organic solvents were tested for the improvement of Raman features by EC-SERS. Taking into account that organic solvents usually have many Raman bands (Figure 1) that could hamper the analysis of the characteristic bands of the molecule of interest, the selection of the solvent must be considered for each application. As proof of concept, the detection of nicotinamide in organic media is carried out by the electrochemical activation of Au electrode. Electrochemical protocol based on an initial oxidation of the electrode surface followed by its reduction, allows the generation of SERS substrates and provides the enhancement of the Raman signal.

Figure 1. Raman spectra of ACN, EtOH, DMSO, DMF and THF.

References

[1] D. Martín-Yerga, A. Junquera-Pérez, M. B. González-García, J. V. Perales-Rondon, A. Heras, A. Colina, D. Hernández-Santos, P. Fanjul-Bolado, Electrochim. Acta 264 (2018) 183-190.

[2] D. Ibáñez, A. Junquera-Pérez, M. B. González-García, D. Hernández-Santos, P. Fanjul-Bolado, Talanta 206 (2020) 120190.

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(Sensor Division Outstanding Achievement Award) Micro/Nano Sensors and Drug Delivery
Authors: Boisen Anja
Published: November 2022

Our research center of excellence ‘IDUN’ combines research in nanosensors/centrifugal microfluidics and microfabricated devices for oral drug delivery. This allows us to explore the synergy between sensor development and search for new pharmaceutical delivery tools and materials. I will show examples of recent findings and results within drug/polymer characterization, microdevices for drug delivery and diagnostics. Also, new applications within therapeutic drug monitoring using Surface Enhanced Raman Scattering will be presented as well as sensor integration with centrifugal microfluidics platforms. In the future our vision is to combine sensing and delivery, to be able to perform e.g. personalized medication.
(Digital Presentation) A Low-Modulus, Soft and Stretchable Wearable Electrocardiography Sensor-System Patch
Authors: Zhang Anan , Tessier Alexandra , Williams Chris , Ameri Shideh Kabiri
Published: November 2022

Electrocardiography (ECG) is a primary tool for diagnosis of various types of disease and disorders such as arrhythmias, coronary heart disease, heart attack, mental disorders, etc. Reliable wearable ECG devices can be a valuable tool in early diagnosis and effective treatment of such disease and disorders. Convention wearable ECG sensor-systems are rigid, bulky, expensive, and the recorded ECG signals using these wearable devices lack required accuracy for medical diagnosis mainly due to motion artifacts that is originated from slippage of sensors on skin and/or instable interface between the soft sensor and the rigid electronic circuits.

Here, we report a low-modulus, soft and stretchable wearable electrocardiography (ECG) sensor-system patch which enables continuous and long-term recording of ECG signals with minimal motion artifacts. This system consists of two reusable, detachable-attachable patches: sensor patch and circuit patch, as shown in Figure 1a. The reusable multi-wall carbon nanotube (MWCNT) based sensor patch is fabricated on stretchable elastomer substrate by our developed cost and time-effective method. Reusable, front-end and wireless circuit patch is made by integration of the off-the-shelf integrated circuit components with three-dimensional (3D) stretchable-deformable interconnects (SDI). SDIs are 3D springs of liquid metal (EGaIn). Unlike other reported liquid metal based interconnects, SDI has been designed in 3D form to increase the stretchability and make it low-modulus and robust to deformations in all directions. The stretchability of SDI structure is beyond 500% (the limit of our measurement system) without any negligible change in electrical resistivity of the interconnects. With less than 1% change in the resistance of SDIs after 50,000 cycles of applied tensile strain of 200%, the SDI structure ensures reliable stretchability and durability of the circuit patch for long-term electrocardiography.

The sensor patch is soft, stretchable and it is fabricated using a low-cost scalable method. This soft and stretchable ECG sensor-system shows comparable performance with respect to medical grade Ag/AgCl wet gel electrodes. Our CNT-PDMS sensors shows low electrode-skin interface impedance and low susceptibility to motion artifact which similar of it in medical grade Ag/AgCl wet gel sensors (Fig. 1b). Further, it is waterproof, reusable and comfortable to wear.

The circuit patch includes a rechargeable battery and ECG signals is wirelessly sent to a personal device such as cellphone, tablet and laptop through Bluetooth low energy (BLE) and it is displayed in real-time (Fig. 1c) Our developed sensor-system is a multi-use platform which can be applied for the detection of EMG, EEG or EOG signals.

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Triboelectric Pressure Sensors Using Laser-Directed Synthesis of Strain-Induced Crumpled MoS2
Authors: Kim Hyunseung , Sohn Changwan , Im Seongbin , Jeong Chang Kyu
Published: November 2022

Two-dimensional (2D) transition metal dichalcogenide (TMDC) nanomaterials are currently regarded as next generation electronic materials for future flexible, transparent, and wearable electronics. Due to the lack of compatible synthesis and study, however, the characteristic influences of 2D TMDC nanomaterials have been little investigated in the field of triboelectric nanogenerator (TENG) devices that are currently one of the main technologies for mechanical energy harvesting. In this report, we demonstrate a fast, non-vacuum, wafer-scale, and patternable synthesis method for 2D MoS2 using pulsed laser-directed thermolysis. The laser-based synthesis technique that we have developed can apply internal stress to MoS2 crystal by adjusting its morphological structure, so that a surface-crumpled MoS2 TENG device generates ~40% more power than a flat MoS2 one. Compared to other MoS2-based TENG devices, it shows high-performance energy harvesting (up to ~25 V and ~1.2 μA) without assistance from other materials, even when the counterpart triboelectric surface has a slightly different triboelectric series. This enhanced triboelectrification is attribute to work function change as well as enlarged surface roughness. Finally, the direct-synthesized MoS2 patterns are utilized to fabricate a self-powered flexible haptic sensor array. The technique we propose here is intended to stimulate further investigation of the triboelectric effects and applications of 2D TMDC nanomaterials.
Peroxynitrite Electrochemical Signature on Selenium and Selenium-Decorated Graphene Depositions
Authors: Kalil Haitham , Ibrahim Magdy A , Fouad Farid , Bayachou Mekki
Published: November 2022

Reactive oxygen species (ROS) such as peroxynitrite have been linked to oxidative stress-induced diseases such as cardiovascular failure. Determining the cause and progression of such disease, as well as testing the efficacy of potential treatments all hinge on the ability to accurately detect these species in biological systems. Antioxidant uses of selenium have garnered the attention of scientists in recent years. Latest investigations have revealed that selenium is essential for redox regulation as a ROS modulator and as a catalytic cofactor of endogenous antioxidative mechanisms.

The advantages of preparing selenium electrochemical depositions as sensitive surfaces for peroxynitrite detection and quantification were revealed in our research. Electrochemical sensors with high sensitivity and selectivity were developed by dissolving selenium dioxide in an acidic medium. Graphene nanostructures loaded with selenium were used to modify one set of glassy carbon electrodes (GCEs), while selenium nanoparticles were used to modify another set of GCEs for comparison purposes. The shape and surface chemistry of selenium and selenium-decorated graphene nanostructures were investigated using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The electrochemical catalytic activity of these systems was determined using cyclic voltammetry and chronoamperometry. The thickness of the deposited selenium interfaces was measured using Quartz Crystal Microbalance (QCM) analysis.

Elemental selenium nanoparticles showed an increase in the sensitivity toward peroxynitrite when embedded into graphene sheets. In addition, it allowed for the use of low positive potential, leading to improved segregation of peroxynitrite from other analytes that are sensitive to higher potentials.
Detection of Lead and Environmental Parameters with Sulfur Film Modification of Screen Print Electrode
Authors: Sontag Philip , Yee Nathan , Miskewitz Robert , Reinfelder John
Published: November 2022

Environmental electrochemical sensors are an exciting field with a high volume of possibilities. Screen print electrodes have a tremendous advantage for environmental applications as they are 1) capable of performing laboratory and field measurements 2) allow a variety of surface science techniques and provide 3) an excellent outreach medium for students to learn about a variety of engineering and scientific disciplines. The use of redox-active (faradaic or “duck curve”) and non-redox (non-faradaic or capacitance) elements were used to detect lead and bicarbonate respectively using cyclic voltammetry. Aims of this project include the performance assessment of a screen print electrode with sulfur films treatments to detect these environmental compounds. This research education and outreach project summarizes efforts made to conduct and disseminate environmental electrochemistry to students in the New Brunswick area and Rutgers University. Remote and in-person learning labs were conducted to teach students fundamentals of electrochemistry and empower an underserved population to pursue science and engineering disciplines.
(Digital Presentation) Graphene Oxide Modified Pencil Graphite Electrode for the Detection of H2O2
Authors: Mistri Jayanta , Rasel Md. , Jamal Mamun
Published: November 2022

Hydrogen peroxide is a very simple molecule, it is an important chemical and analyte in various industry fields, such as mining, environment, pharmaceutical, food manufacturing and textile applications. Meanwhile, H2O2 is also a kind of toxic by-product of many biological oxidases, based on which H2O2 has been considered to be an indicator of related diseases, such as Parkinson disease, cancer, stroke, arteriosclerosis and Alzheimer disease [1-3]. In addition, H2O2 has been applied in liquid-based fuel cells as an efficient oxidant and has also been employed in organic synthesis. Therefore, it is one of the critical issues to detect H2O2 accurately for industrial needs.

In this work reduced graphene oxide-supported tin oxide nano clusters modified pencil graphite electrode (SnO2-rGO/PGE) was used as electrochemical sensing material for H2O2 detection. Cyclic voltammetry and amperometry were used to investigate the catalytic properties of SnO2-rGO/PGE. Hydrothermal synthesis method was used for the fabrication of SnO2 nanoparticles and GO prepared by modified Hummers method. For the detection of H2O2, the nanoparticles were mixed with Nafion and chitosan before drop coating onto the Pencil graphite electrode (PGE) surface. This studies we found a good catalytic activities on 3B pencil that modifier with GO and SnO2nano clusters at pH (7.4). Here, include that the current increasing after using modifier PGE with nanoparticles. Electrochemical studies showed that the sensing platform fabricated from SnO2-rGO possesses fast mass transport, good electrical conductivity and high sensitivity and selectivity for the detection of H2O2.Where, composite SnO2-Go/PGE exhibited amperometric sensitivity of 129 μAmM−1cm-2 and fast response time 2s.The interference study of SnO2-rGO has been found a significant current response for H2O2 compared to the uric acid and ascorbic acid.The electrode can be prepared simply and at low cost, and present a promising tool for sensing H2O2. Here we propose a new, robust and reliable way to detect of H2O2.

Acknowledgments

Ministry of Science and Technology of Bangladesh (special allocation 2021-22) for funding this research.

Reference

J. Islam et al., PLoS ONE, 2021 16(3), e0248142.

Roy, K., et al.
Int. J. Environ. Sci. Technol. (2022). DOI: https://doi.org/10.1007/s13762-022-04301-w
Measurement and Analysis of Mechanical Properties of All-Solid-State Electrodes Fabricated By Dry Process with Saicas
Authors: Bak Cheol , Lee Jong Jun , Kim Dohwan , Lee Yong Min
Published: November 2022

Due to battery fire accidents while driving and charging an electric vehicle, research on improving battery safety as well as increasing the energy density has been extensively performed. For this purpose, an all-solid-state battery without the flammable liquid electrolyte is being more actively conducted. Among various solid electrolyte types, the sulfide-based solid electrolyte has been investigated as the most promising candidate owing to its high ionic conductivity and ductility. However, since sulfide solid electrolyte is too reactive to organic solvents like N-methyl pyrrolidone, a few nonpolar solvents (xylene or toluene) can be used to fabricate sulfide solid electrolyte. Thus, except for rubber binders such as nitrile butadiene rubber, other conventional adhesive binders are excluded from candidates. So, to solve this limitation fundamentally, a dry process without any solvents must be an attractive method for using the sulfide electrolyte in battery manufacturing process. For example, polytetrafluoroethylene (PTFE) is frequently used for fabricating all-solid-state electrode (ASSE) with sulfide electrolytes due to its wonderful fibrilization property. However, comparing to the wet process, it is more challenging to distribute all the electrode components uniformly in the dry process, where all the components are mixed through kneading the electrode dough. That is, to maximize the electrochemical performances of ASSEs, it is essential to evaluate the mechanical properties of ASSEs fabricated from dry process and to quantify them for optimization. However, most of research on ASSEs have been focused on their electrochemical performances up to now.

Thus, in this work, we attempted to measure the mechanical properties of ASSEs with sulfide electrolyte using a surface and interfacial cutting analysis system (SAICAS). The ASSEs were fabricated through dry process while changing the PTFE binder content. Subsequently, both bulk and interfacial adhesive strengths were analyzed systematically and deliberately by a few μm resolution. Furthermore, to unveil the surface, bulk, and interfacial electrical properties are also measured using an electrode resistance measuring instrument (HIOKI RM2610). Thus, we can provide a correlation between binder content and mechanical/electrical properties of dry ASSEs. Finally, comparative results based on wet processed ASSEs will also be included in this work.
A Fluorine-Based Linear Carbonate Electrolyte Additive for Enhanced High-Voltage Cycle Performance of Li-Metal Secondary Batteries
Authors: Han Jiwon , Jin Dahee , Park Changhee , Lee Sunggi , Lee Yong Min
Published: November 2022

Due to growing demand for electric vehicles (EVs) and energy storage systems (ESS), it is essential to meet the requirement for high energy density of Li secondary batteries. In this sense, an electrode chemistry matching high-Ni cathode materials and thin Li metal anode has been investigated most actively under high voltage operation. As a result, there are a variety of degradation issues on both electrodes like high-resistance cathode electrolyte interphase (CEI) as well as solid electrolyte interphase (SEI) on the anode, electrolyte depletion, or Li dendritic growth. Thus, advanced electrolytes containing functional additives are extensively being developed to mitigate those stresses occurred in the high-energy-density Li-metal secondary batteries (LMSBs). Especially, to minimize the amount of expensive additives, many research groups have made much effort in discovering new or multi-functional additives for LMSBs.

In this work, we report a bis(2-fluoroethyl) carbonate (B-FEC) as a new fluorine-based linear carbonate electrolyte additive to stabilize the SEI even in the high voltage conditions (4.5 V cut-off). To confirm the role of B-FEC on electrochemical properties, we evaluated its electrochemical properties with Li/Li symmetric cells as well as LiNi0.6Co0.2Mn0.2O2 (NCM 622)/Li cells with or without B-FEC. Also, various analysis data were also gathered to check the morphological and compositional changes caused by B-FEC through SEM, XPS, etc.
Disentangling Plasmonic and Catalytic Effects in a Practical Plasmon-Enhanced Lithium–Oxygen Battery
Authors: Chae Kyunghee , Kim Minju , Marques Mota Filipe , Kim Dong Ha
Published: November 2022

Rechargeable Li–O2 batteries have high theoretical energy density (~3600 Wh kg-1) compared to the conventional Li–ion batteries. However, the recharging process is primarily disturbed by the large overpotential attributed to the sluggish OER kinetics. Very recently, photo-assisted Li–O2 batteries with semiconductor-containing cathodes have gained attention as a promising approach for enhanced energy storage. Surface plasmon resonance (SPR), the unique property of plasmonic materials (such as Au, Ag, Cu, Pd, and Al) interacting with light, has found increasing application in catalysis. Here, we demonstrate plasmonic effects in Li–O2 systems by incorporating gold nanoparticles on a practical Ketjen Black cathode with different amounts and sizes. During discharge, plasmonic Au NPs induce a Li2O2 morphology change to small particles, which are easily decomposed during recharge. Most importantly, the SPR-induced hot carriers help to form and decompose Li2O2 and suppress carboxylate side-products, decreasing recharge voltages and increasing the round-trip efficiency up to 80.2%. Meticulous analyses of the catalytic properties of the Au NPs and the SPR-induced near-field enhancement and local heat effects are here additionally shared.
Nonprecious Multi-Principal Metal Systems As the Air Electrode for a Solid-State Rechargeable Zinc-Air Battery
Authors: Madan Chetna , Halder Aditi
Published: November 2022

Zinc-air battery technology is gaining recognition as a promising energy storage device to be used in portable electronics and electric vehicles. Despite possessing high theoretical energy density, environmental and operational safety, and easy accessibility of zinc reservoirs, the successful commercialization of zinc-air batteries suffers due to the poor oxygen electrocatalysis kinetics at the air cathode. The kinetically inept oxygen reduction and oxygen evolution reactions at the cathode lead to a large overpotential barrier and poor charge-discharge cyclic performance of the rechargeable zinc-air battery. This work demonstrates designing a multi-principal metal bifunctional electrocatalyst that is directly deposited on conductive, porous, and flexible substrates to eliminate the necessity of polymeric binders. The flexible bifunctional oxygen electrocatalyst used for the cathode of solid-state ZAB is assembled with gel polymer electrolyte and zinc anode giving excellent charge-discharge cyclic stability and constant discharge voltage (close to 1.65 V). These multi-principal metal electrocatalysts constituting quasi-equimolar concentration, provide numerous combinations of surface functionality, multiple adsorption sites, and electronic environments thus enabling better optimization of the catalytic performance.
The Effects of Time, Pressure, Temperature, and the Cell Ideal Time on Direct Contact Prelithiation of Si-C Anode
Authors: Gautam Manoj , Mishra Govind Kumar , Ahuja Aakash , Sau Supriya , Furquan Mohammad , Mitra Sagar
Published: November 2022

In the commercial industry, lithium-ion batteries (LIB) with a high energy density have already received more attention. The need for high-energy LIB for electric vehicles (60-70 kWh to travel 300 miles) has prompted research into next-generation battery materials. As an anode material, composite Si has been shown to have better cycle stability than bare Si. However, the initial capacity loss (ICL) of Si anode is high due to the formation of surface film compounds on the anode surface during the first discharge process, and it is irreversible in nature. Direct contact prelithiation (PL) is a simple, practical, and scalable technique for overcoming first cycle loss and large volume expansion difficulties in silicon anode (with 30 wt percent Si loading) material, but no comprehensive research has been done on it. The effect of externally applied pressure (weight), microstructure, and operating temperature have all been investigated in order to gain a better knowledge of direct contact PL as a function of PL time. Electrochemical techniques and other microstructural analyses were used to investigate the impact of PL on Si-C electrode surfaces. The thickness of the SEI layer increases as the PL time increases and diminishes after 2 minutes. With a 20 g externally applied weight, the appropriate PL time was found to be between 15 (PL-15) and 30 (PL-30) minutes, with 83.5 % and 97.3 % initial Coulombic efficiency (ICE), respectively. The PL-15 and PL-30 cells had higher cyclic stability than the PL-0 (without prelithiation), retaining more than 90% of capacity retention after 500 cycles at a current density of 1 A g-1. The highest discharge capacity was reported for PL-15 and PL-30 at 45°C operating temperature with limited cyclability. To obtain superior cell performance, we propose a synchronized method in prelithiation time, pressure, and temperature.

Figure 1
A Generic Battery Cycling Optimization Framework with Learned Sampling and Early Stopping Strategies
Authors: Deng Changyu , Lu Wei
Published: November 2022

Battery optimization is a challenging task due to the large amount of cost and time required to evaluate different configurations in experiment or simulation. It is especially costly to optimize cycling performance since cycling the batteries is costly and time-consuming. In this project, we report an optimization framework with learned sampling and early stopping strategies, designed to optimize battery parameters in an efficient way to reduce total cycling time. It consists of a pruner and a sampler. The pruner stops unpromising cycling batteries to save the budget for further exploration. The sampler can predict the next promising configurations based on query history. The framework can deal with categorical, discrete and continuous parameters, and can run in an asynchronously parallel way to allow multiple simultaneous cycling cells. We demonstrated the performance by a parameter fitting problem for a calendar aging model. Comparisons with current methods are made to demonstrate the effectiveness of our method to reduce cycling time. Our framework can foster battery optimization in simulations and experiments.
(Digital Presentation) The Effect of Phosphorus on the Mechanism of Pitting Initiation in Carbon Steel
Authors: Takayama Riku , Muto Izumi , Nishimoto Masashi , Sato Haruka , Sugawara Yu
Published: November 2022

Phosphorus is typical impurity in steelmaking process. Phosphorus was tended to segregate at grain boundaries. Phosphorus segregation causes solidification clacking at welding and defects at forming. In the steel making process, Phosphorus cannot refine completely. We focused on the effect of phosphorus segregation and precipitation to corrosion resistance. Phosphorus in steel was expected solid solution, segregation, and precipitation and the size was submicron order. Therefore, we need microelectrochemical measurements to analysis. Solid solution carbon was improved corrosion resistance was known1). To analysis only the effect of phosphorus, we use Fe-P binary alloy. In this study, we assessed pitting initiation of Fe-P binary alloy using microelectrochemical measurement.

Two types of heat-treatment were conducted to Fe-P binary alloy. The one was heat-treated at 1100 ℃ at 1 h and quenched in water. The other was tempered at 1373 K for 1 h. As-tempered steel was aimed to precipitate of Fe3P. The specimen surface was polished down to 1 μm using a diamond paste. Pure iron was used as reference materials.

Potentiodynamic anodic polarization curves were measured in Boric-Borate buffer with 5 mM NaCl solution. The pH value of the solution was adjusted to 7.0. Size of electrode areas were 1 cm × 1 cm, 1 mm × 1 mm, and 0.5 mm × 0.5 mm.

When the size of electrode area was 1 cm × 1 cm, pitting potential of Fe-P was increased above pure iron. In 1 mm × 1 mm electrode area, as-tempered steel was shown the higher pitting potential than as-quenched steel. Pitting was only observed from edge of masking. In 0.5 mm × 0.5 mm electrode area, no pitting was observed on both as-quenched and as- tempered steel.

Reference;

1) Kadowaki, I. Muto, Y Sugawara, T. Doi, K. Kawano, and N. Hara, J. Electrochem. Soc., 165, C711 (2018).
Development of Slurry Formulations for Molybdenum-Chemical Mechanical Planarization (Mo-CMP)
Authors: Dudek Abigail L. , Keleher Jason J.
Published: November 2022

As integrated circuit (IC) technology continues to advance, the challenge to extend Moore’s law without sacrificing power density and energy efficiency is critical. One method of achieving these goals is through the utilization of Chemical Mechanical Planarization (CMP) to achieve surface planarity down to angstrom level uniformity. Current IC architecture relies on the integration of Cu wiring into Si (i.e., TEOS) substrates to provide effective power transfer. However, this traditional design is limited in efficiency for smaller, high-powered devices which require increased insulating properties. To combat these limitations, low resistivity metals (i.e., Ta, TaN, Mo, etc.) are incorporated for their inherent resistance to electromigration. More specifically, Mo has become increasing attractive due to the metal’s thermal stability and compatibility with Cu to serve as an efficient diffusive barrier. These ideal characteristics ultimately lead to the challenge of increased hardness resulting from inherent inert properties leading to the inhibition of effective CMP processes. To overcome this challenge, Mo-CMP involves the use of harsh polishing conditions consisting of high pressure-velocity coupled with complex slurry dispersions containing aggressive redox chemistry (i.e., KMnO4, KIO3, APS, etc.) and high abrasive nanoparticle content (i.e., Al2O3, SiO2, etc.). More specifically, the utilization of harsh oxidizers and alkaline conditions results in a metal oxide film ideal for effective material removal rate (MRR). However, it is with the implementation of these conditions that ultimately results in the generation of surface defects (i.e. scratching, pitting, etching, organic residues, galvanic corrosion, etc.) which are detrimental to the performance (i.e., power efficiency, operating frequency, etc.) for next generation IC devices. This work will focus on the investigation into conditions leading to effective MRR in Mo-CMP. More specifically, this work will utilize a suite of dynamic analytical techniques (i.e. atomic force microscopy, scanning electron microscopy, quartz crystal microbalance, contact angle, electrochemical analysis, etc.) to evaluate interfacial reaction mechanisms that lead to the productive modification for the reduction of shear force during polishing. It has been shown that the incorporation of tailored chemistries and the addition of “softer” passivating agents (i.e., polyamines) can result in the formation of surface-active complexes that trigger rapid interfacial redox reactions in H2O2 environments at a more amenable pH. Increasing the chemistry’s surface activity to Mo will result in a decreased Ea limiting the effects of nanoparticle adsorption to reduce CMP induced defectivity without the expense of corrosion events necessary for MRR. Furthermore, the implementation of “softer” passivating agents can reduce the galvanic corrosion effects with Cu which significantly reduce secondary defectivity.