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Preparations And Sodium Storage Properties Of Ni3S2@Cnt Composite, Ming-Tao Duan, Yan-Shuang Meng, Hong-Shuai Zhang Dec 2020

Preparations And Sodium Storage Properties Of Ni3S2@Cnt Composite, Ming-Tao Duan, Yan-Shuang Meng, Hong-Shuai Zhang

Journal of Electrochemistry

Transition metal sulfides (TMSs)-based electrode materials with highly reversible sodium storage have attracted extensive attentions as one of the most prospective electrode materials for sodium ion batteries (SIBs). However, low cycling stability and rate property caused by large volume expansion and poor electronic conductivity during the electrochemical reaction still hamper their further practical application. In this work, in-situ encapsulated Ni3S2 nanoparticles in carbon nanotubes (Ni3S2@CNT) have been successfully fabricated as an anode material for high-performance SIBs by a one-step solid-phase calcination process. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), …


Step-By-Step Modification Of Graphite Felt Electrode For Vanadium Redox Flow Battery, Jing-Yuan Lou, Dong-Jiang You, Xue-Jing Li Dec 2020

Step-By-Step Modification Of Graphite Felt Electrode For Vanadium Redox Flow Battery, Jing-Yuan Lou, Dong-Jiang You, Xue-Jing Li

Journal of Electrochemistry

As a well-known electrode material of the vanadium redox flow battery (VRFB),graphite felt electrode is the frequently-used electrode material in VRFB, and its low electrochemical activity is one of the key factors for the low power density of VRFB. In this work, we proposed a step-by-step modification method, which used KMnO4 to oxidize graphite felt first and then placed in an activation solution to excite its reactivity, to improve the electrochemical performance of the graphite felt electrode. According to the results from cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) characterizations …


Degradation And Thermal Characteristics Of Lini0.8Co0.15Al0.05O2/Graphite Lithium Ion Battery After Different State Of Charge Ranges Cycling, Cun Wang, Wei-Jiang Zhang, Teng-Fei He, Bo Lei, You-Jie Shi, Yao-Dong Zheng, Wei-Lin Luo, Fang-Ming Jiang Dec 2020

Degradation And Thermal Characteristics Of Lini0.8Co0.15Al0.05O2/Graphite Lithium Ion Battery After Different State Of Charge Ranges Cycling, Cun Wang, Wei-Jiang Zhang, Teng-Fei He, Bo Lei, You-Jie Shi, Yao-Dong Zheng, Wei-Lin Luo, Fang-Ming Jiang

Journal of Electrochemistry

The LiNi0.8Co0.15Al0.05O2 (NCA) cathode exhibits high energy density and large reversible capacity, which plays an essential role in the field of electric vehicles (EVs). However, low capacity retention and poor thermal stability limit its application. Few literatures are found for the capacity degradation mechanism of NCA/graphite batteries at home and abroad. The different state of charge (SOC) ranges cycle degradation behaviors of 18650-type NCA/graphite (2.4 Ah) battery were studied in this paper. The SOC ranges considered were 0% ~ 20% (low), 20% ~ 70% (medium), 70% ~ 100% (high), and 0% ~ 100% …


Effect Of Reaction Conditions On Cu⁃Catalyzed Co2 Electroreduction, Chang Zhu, Wei Chen, Yan-Fang Song, Xiao Dong, Gui-Hua Li, Wei Wei, Yu-Han Sun Dec 2020

Effect Of Reaction Conditions On Cu⁃Catalyzed Co2 Electroreduction, Chang Zhu, Wei Chen, Yan-Fang Song, Xiao Dong, Gui-Hua Li, Wei Wei, Yu-Han Sun

Journal of Electrochemistry

Electrochemical conversion of carbon dioxide (CO2) driven by renewable electricity that can meet both carbon emission reduction and renewable energy utilization has been rapidly developed in recent years. Copper (Cu) catalyst has long been a promising candidate for CO2 electroreduction applications because of its natural abundance and specific capability of producing a substantial amount of C2 products. However, various metallic Cu electrodes reported have been significantly influenced by the adsorption of certain cation/anion ions, resulting in wide-span catalytic activities and selectivity for various products. In addition, a recent report demonstrated that by virtue of gas-diffusion flow cell …


Preparation And Process Optimization Of Cathode Materials For Lithium-Sulfur Batteries, Kai Wu Dec 2020

Preparation And Process Optimization Of Cathode Materials For Lithium-Sulfur Batteries, Kai Wu

Journal of Electrochemistry

Lithium-sulfur (Li-S) batteries represent promising candidates for next-generation energy storage system due to their high energy density and low material cost. However, the industrial application of Li-S batteries remains challenges because of the shuttle effect from lithium polysulfides and the lack of facial routes for Li-S battery preparation. To solve these problems, a cathode consisting of different commercial carbon materials, namely, acetylene black (SP), Ketjen Black (KB) and carbon nanotube (CNT), with sulfur (S) is prepared separately for Li-S battery. After the process of 8-h ball milling for KB/S composite, together with the polyvinyl pyrrolidone (PVP) binder, the cathode could …


Effect Of Stereotaxically-Constructed Graphene On The Negative Electrode Performance Of Lead-Acid Batteries, Pin-Song Chen, Yi-Tao Hu, Xin-Yi Zhang, Pei-Kang Shen Dec 2020

Effect Of Stereotaxically-Constructed Graphene On The Negative Electrode Performance Of Lead-Acid Batteries, Pin-Song Chen, Yi-Tao Hu, Xin-Yi Zhang, Pei-Kang Shen

Journal of Electrochemistry

With the advantages of high ratio surface area, excellent conductivity and high stability, the stereotaxically-constructed graphene (SCG) material was added to the negative active material (NAM) of lead-acid battery for improving battery performance. XRD, SEM and cyclic voltammetry tests were carried out to analyze the influence of SCG on negative active material. It is found that the conversion efficiency of lead sulfate to lead in the negative active material added with SCG material was higher than that of control group, and the particle size of the lead sulfate obtained after the discharge reaction was smaller, which are favorable factors for …


Core-Shell Structured Ru@Ptru Nanoflower Electrocatalysts Toward Alkaline Hydrogen Evolution Reaction, Xue-Liang Wang, Yuan-Yuan Cong, Chen-Xi Qiu, Sheng-Jie Wang, Jia-Qi Qin, Yu-Jiang Song Dec 2020

Core-Shell Structured Ru@Ptru Nanoflower Electrocatalysts Toward Alkaline Hydrogen Evolution Reaction, Xue-Liang Wang, Yuan-Yuan Cong, Chen-Xi Qiu, Sheng-Jie Wang, Jia-Qi Qin, Yu-Jiang Song

Journal of Electrochemistry

Water electrolysis for hydrogen production is beneficial for solving the problem of energy crisis and environmental issues. It is necessary to study highly active and cost-effective catalysts toward hydrogen evolution reaction (HER) to reduce the consumption of noble metals. Herein, we report the synthesis of core-shell structured Ru@Pt0.24Ru nanoflowers electrocatalyst by stepwise reduction of Ru and Pt precursors in the mixture of oleylamine and benzyl alcohol at 160 oC. The average diameter of the resultant Ru@Pt0.24Ru was 16.5±4.0 nm with a bulk atomic ratio between Pt and Ru of 0.24:1 and a surface ratio of 3.3:1 …


Preparations And Photoelectrochemical Performances Of Rgo-Tio2 Nanotubes Arrays, Ze-Yang Zhang, Lan Sun, Chang-Jian Lin Dec 2020

Preparations And Photoelectrochemical Performances Of Rgo-Tio2 Nanotubes Arrays, Ze-Yang Zhang, Lan Sun, Chang-Jian Lin

Journal of Electrochemistry

Decorating TiO2 nanotube arrays with RGO to improve the photocatalytic activity of TiO2 nanotube arrays has been reported. For the reported RGO-TiO2 nanotube arrays, TiO2 nanotube arrays were prepared by anodizing the high-purity Ti foil in an organic electrolyte for multiple-step treatments, while RGO were deposited on TiO2 nanotube arrays by using cyclic voltammetry or other electrical reduction methods. To enhance the reduction degree and the coverage of RGO on the resultant RGO-TiO2 nanotube arrays, in this work, the one-step electrochemical anodization in hydrofluoric acid was used to fabricate TiO2 nanotube arrays with …


Numerical Simulations Of Current And Temperature Distribution Of Symmetrical Double-Cathode Solid Oxide Fuel Cell Stacks Based On The Theory Of Electric-Chemical-Thermal Coupling, Cheng-Rong Yu, Jian-Guo Zhu, Cong-Ying Jiang, Yu-Chen Gu, Ye-Xin Zhou, Zhuo-Bin Li, Rong-Min Wu, Zheng Zhong, Wan-Bing Guan Dec 2020

Numerical Simulations Of Current And Temperature Distribution Of Symmetrical Double-Cathode Solid Oxide Fuel Cell Stacks Based On The Theory Of Electric-Chemical-Thermal Coupling, Cheng-Rong Yu, Jian-Guo Zhu, Cong-Ying Jiang, Yu-Chen Gu, Ye-Xin Zhou, Zhuo-Bin Li, Rong-Min Wu, Zheng Zhong, Wan-Bing Guan

Journal of Electrochemistry

Solid oxide fuel cell (SOFC) is a high-efficient clean conversion device for future energy management. Because of the low antioxidant reduction ability and complex thermal stress, the structure of traditional asymmetrical thin anode-supported planar SOFC is easily to be broken under stack operating conditions. To overcome these defects, a new complete symmetrical SOFC based on double-sided cathodes was developed. To study the influences of gas flow direction and current collection mode on the cell performance inside stack, a numerical model was established by finite element method based on the theory of electro-thermo-chemo multiphysical coupling. By applying this model, the molar …


Licoo2 As Sulfur Host To Enhance Cathode Volumetric Capacity For Lithium-Sulfur Battery, Lu Wang, Xue-Ping Gao Oct 2020

Licoo2 As Sulfur Host To Enhance Cathode Volumetric Capacity For Lithium-Sulfur Battery, Lu Wang, Xue-Ping Gao

Journal of Electrochemistry

Lithium-sulfur battery is one of the most promising secondary battery systems due to its super high theoretical gravimetric and volumetric energy densities (2600 Wh·kg-1 and 2800 Wh·L-1, respectively). However, the practical volumetric capacity of sulfur cathode is still unsatisfied due to the overuse of low-density host materials, such as carbon nanomaterials. Herein, commercial LiCoO2 with the high tap density of 2.94 g·cm-3 was used as the host material to build high density sulfur-based composite and compact electrode for increasing the volumetric capacity. Obviously, the tap density of the as-prepared S/LiCoO2 composite was 1.90 g·cm-3, larger than that of …


Research Progress Of Key Components In Lithium-Sulfur Batteries, Jia-Jia Chen, Quan-Feng Dong Oct 2020

Research Progress Of Key Components In Lithium-Sulfur Batteries, Jia-Jia Chen, Quan-Feng Dong

Journal of Electrochemistry

Due to the much higher theoretical specific capacity and energy density than the ones of traditional lithium ion battery, Li-S batteries have long been at the pinnacle in the realms of high-energy Li-metal batteries. However, the complicated electrochemical reactions on the sulfur cathode and Li anode, induced by the thermodynamic and kinetic behaviors of lithium polysulfides, are the intrinsic bottleneck to realize the full potential of Li-S batteries for practical application. In this review, we firstly discuss the roles, and thermodynamic and kinetic behaviors of polysulfides in the charging and discharging processes of Li-S batteries. Then, the functional design and …


Facile Synthesis Of Nitrogen-Doped Graphene-Like Active Carbon Materials For High Performance Lithium-Sulfur Battery, Quan-Hua Meng, Wen-Wen Deng, Chang-Ming Li Oct 2020

Facile Synthesis Of Nitrogen-Doped Graphene-Like Active Carbon Materials For High Performance Lithium-Sulfur Battery, Quan-Hua Meng, Wen-Wen Deng, Chang-Ming Li

Journal of Electrochemistry

Lithium-sulphur (Li-S) battery is regarded as a promising energy storage device because of its high theoretical capacity. However, the low S utilization and short cycling life limit the commercial applications. In this work, nitrogen-doped graphene-like carbon (NGC) materials were synthesized by simply pyrolyzing and carbonizing the mixture of melamine (C3H6N6) and L-cysteine (C3H7NO2S). The graphene-like structure in NGC effectively buffered the volume change of S during the discharge/charge process and improved the cycling stability. Meanwhile, nitrogen-containing functional groups in NGC facilitated the transportation of ions and suppressed the …


Progress And Prospects On Multifunctional Coating Separators For Lithium-Sulfur Battery, Zhuang-Zhuang Wei, Nan-Xiang Zhang, Feng Wu, Ren-Jie Chen Oct 2020

Progress And Prospects On Multifunctional Coating Separators For Lithium-Sulfur Battery, Zhuang-Zhuang Wei, Nan-Xiang Zhang, Feng Wu, Ren-Jie Chen

Journal of Electrochemistry

The development of advanced energy storage systems is crucial to meet the growing demand for electric vehicles, portable devices and renewable energy storage. Lithium-sulfur (Li-S) batteries, with their advantages of high specific energy, low cost of raw materials and environmental friendliness, are hotspots in the research field of new high performance batteries. However, there are still many problems which hinder the practical applications of lithium-sulfur batteries, such as the shuttle effect of soluble polysulfide intermediates, the growth of lithium dendrites, and the thermal stability and safety of lithium-sulfur batteries during use. The design of multifunctional coating separator is one of …


Electrochemical Engineering Of Carbon Nanodots, Lei Bao, Dai-Wen Pang Oct 2020

Electrochemical Engineering Of Carbon Nanodots, Lei Bao, Dai-Wen Pang

Journal of Electrochemistry

Carbon nanodots (CNDs), as zero-dimensional carbonaceous fluorescent nanomaterials, are valuable add-ons to the current cohorts of fluorescent nanoparticles. The fine control over the size and the surface is the key to gain designated photophysical properties of CNDs as well as empowers CNDs in many applications. Herein, a series of electrochemical strategies to manipulate the size and the surface of CNDs and to identify the surface structures was presented. Accordingly, the understandings on the originals of photoluminescence as well as the pathways of electrochemiluminescence of CNDs were revealed. These studies demonstrated that electrochemical methods were easy to operate, cost-effective and efficient …


Research Progress Of Sulfur Cathode Catalytic Conversions For Lithium-Sulfur Batteries, Qin-Jun Shao, Jian Chen Oct 2020

Research Progress Of Sulfur Cathode Catalytic Conversions For Lithium-Sulfur Batteries, Qin-Jun Shao, Jian Chen

Journal of Electrochemistry

The electrochemical reduction of sulfur (S) takes place through multistep reactions when S is used as a cathode material. The complete discharge of S to form final product lithium sulfide (Li2S) is a two-electron reaction. The formation of low-order lithium polysulfides (LiPS) needs to overcome certain energy barriers. And the reduction of Li2S2 to Li2S is the rate-limited step. The reaction kinetic of sulfur cathode is the critical key to determine the electrochemical performance of Li-S batteries, such as specific energy, specific power and low temperature performance, etc. Accelerating the rate-limited step kinetics …


A Model For The Anodic Carbonization Of Alkaline Polymer Electrolyte Fuel Cells, Qi-Hao Li, Ying-Ming Wang, Hua-Long Ma, Li Xiao, Gong-Wei Wang, Jun-Tao Lu, Lin Zhuang Oct 2020

A Model For The Anodic Carbonization Of Alkaline Polymer Electrolyte Fuel Cells, Qi-Hao Li, Ying-Ming Wang, Hua-Long Ma, Li Xiao, Gong-Wei Wang, Jun-Tao Lu, Lin Zhuang

Journal of Electrochemistry

The alkaline polymer electrolyte fuel cell (APEFC) has made appreciable progress in recent years but is still suffering performance loss during discharge with air as the oxidant. Several theories have been suggested to interpret the loss. However, efforts are still needed to reach a clear quantitative understanding. Based on the major experimental findings in combination with thermodynamics and kinetics of the reactions involved in the anode, this paper presents a model featuring layered carbonization in the anode and relevant grouped equations. The simulation results generated from the latter are compared with experiments, and possible principles to suppress the performance loss …


Porous-Electrode Theory Of Lithium Ion Battery: Old Paradigm And New Challenge, Xiao-Xiao Wang, Zi-Rui Zhou, Qiang Shan, Zeng-Ming Zhang, Jun Huang, Yu-Wen Liu, Sheng-Li Chen Oct 2020

Porous-Electrode Theory Of Lithium Ion Battery: Old Paradigm And New Challenge, Xiao-Xiao Wang, Zi-Rui Zhou, Qiang Shan, Zeng-Ming Zhang, Jun Huang, Yu-Wen Liu, Sheng-Li Chen

Journal of Electrochemistry

A critical review on the porous electrode theory developed by Newman and his colleagues is presented. We propose several ideas for further development of this theory by analyzing its limitations. The classical Newman theory does not consider ion steric effect in describing ion transport in electrolyte solutions, which can be amended by a newly developed ion-vacancy coupled charge transfer model for ion transport in concentrated solutions. Ion transport in solid particles of active materials is essentially an ion-electron coupled transport process, and its rationality is verified by comparing the calculated and experimental diffusion coefficients of Li + ion in intercalation …


High Wind Alerts: A System Created With Observations From The X-Band Teaching And Research Radar, Lauren Warner Aug 2020

High Wind Alerts: A System Created With Observations From The X-Band Teaching And Research Radar, Lauren Warner

The Journal of Purdue Undergraduate Research

Following the August 13, 2011, Indiana State Fair stage collapse tragedy, caused by a wind gust from an approaching thunderstorm, Purdue University enforced a wind speed restriction of 30 mph (13 m s-1) for tents at outdoor events. During these events, volunteers stand outside with handheld anemometers, measuring and reporting when the wind speeds exceed this limit. In this study, we report testing of a new system to automate high-wind alerts based on observations from a Doppler radar, the X-band Teaching and Research Radar (XTRRA), near Purdue’s campus. XTRRA scans over campus at low elevations approximately every 5 minutes. Using …


A Review Of Electrochemical Energy Storage Researches In The Past 22 Years, Yu-Sheng Yang Aug 2020

A Review Of Electrochemical Energy Storage Researches In The Past 22 Years, Yu-Sheng Yang

Journal of Electrochemistry

In this paper, research activities from my groups in the field of electrochemical energy storage are reviewed for the past 22 years, which is divided into three sections. The first section describes the researches related to high specific energy and high specific power energy storage devices, including lithium sulfur batteriies (sulfur composite cathode material, lithium sulfur battery fabrication, lithium boron alloy as lithium sulfur battery anodes, and sulfur lithium-ion battery new system), supercapacitors (super activated carbon, capacitive carbon prepared from phenolic resin, carbon nanotube array parasitic pseudo-capacitive energy storage materials, necessary properties of capacitive carbons, nickel hydroxide xerogels pseudo-capacitive energy …


Fuel Cell Performance Of Non-Precious Metal Based Electrocatalysts, Yan-Feng Zhang, Fei Xiao, Guang-Yu Chen, Min-Hua Shao Aug 2020

Fuel Cell Performance Of Non-Precious Metal Based Electrocatalysts, Yan-Feng Zhang, Fei Xiao, Guang-Yu Chen, Min-Hua Shao

Journal of Electrochemistry

The commercialization of proton exchange membrane fuel cells (PEMFCs) is hindered by high cost and low durability of Pt based electrocatalysts. Developing efficient and durable non-precious metal catalysts is a promising approach to addressing these conundrums. Among them, transition metals dispersed in a nitrogen (N)-doped carbon support (M-N-C) show good oxygen reduction reaction activity. This article reviews recent progress in M-N-C catalysts development, focusing on the catalysts design, membrane electrode assembly fabrication, fuel cell performance, and durability testing. Template-assisted approach is an efficient way to synthesize M-N-C materials with homogeneously dispersed single atom active site and reduced metal particles, carbides …


Electrochemical Carbon Dioxide Reduction In Flow Cells, Jia Fan, Na Han, Yan-Guang Li Aug 2020

Electrochemical Carbon Dioxide Reduction In Flow Cells, Jia Fan, Na Han, Yan-Guang Li

Journal of Electrochemistry

Electrochemical carbon dioxide reduction (CO2RR) is an appealing approach to convert atmospheric CO2 to value-added fuels and industrial chemicals, and may play an important role during the transition to a carbon-neutral economy. In order to make this technology commercially viable, it is essential to pursue CO2RR in flow reactors instead of conventional H-type reactors, and to combine electrocatalyst development with system engineering. In this review, we overview the cell configurations and performance advantages of the two types of flow reactors, analyze their shortcomings, and discuss the effects of their different components including gas diffusion electrode …


Recent Progress In Bifunctional Catalysts For Zinc-Air Batteries, Neng-Neng Xu, Jin-Li Qiao Aug 2020

Recent Progress In Bifunctional Catalysts For Zinc-Air Batteries, Neng-Neng Xu, Jin-Li Qiao

Journal of Electrochemistry

Zinc-air battery has attracted great attention from researchers due to its high energy density and power density, which is expected to be widely used in energy conversion and storage. Air electrode as the core area of oxygen catalytic reaction is the focus of the entire zinc-air battery research. Recently, many research achievements have been made in non-noble metal bifunctional catalysts/electrodes with high activity, low cost and abundant species. In this review, we mainly focus on the reaction mechanism and the recent progress in non-noble metal oxide catalyst, carbon-based catalyst, and carbon-based transition metal compound composite and self-supporting electrode. In addition, …


Research Progress Of Metal-Nitrogen-Carbon Catalysts Toward Oxygen Reduction Reaction Inm Changchun Institute Of Applied Chemistry, Ming-Jun Xu, Jie Liu, Jun-Jie Ge, Chang-Peng Liu, Wei Xing Aug 2020

Research Progress Of Metal-Nitrogen-Carbon Catalysts Toward Oxygen Reduction Reaction Inm Changchun Institute Of Applied Chemistry, Ming-Jun Xu, Jie Liu, Jun-Jie Ge, Chang-Peng Liu, Wei Xing

Journal of Electrochemistry

The development of highly active and stable catalysts toward oxygen reduction reaction (ORR) has been facing severe challenges. In recent years, pyrolytic M-N-C catalysts and metal-organic framework derived materials made the performance of non-noble metal catalysts greatly improved, however, the molecular and atomic level understanding in the reaction active sites and the mechanism are still lacking. Here, we summarize the recent research progress made in the Changchun Institute of Applied Chemistry. We present a microporous metal-organic-framework confined strategy toward the preferable formation of ORR catalysts. Firstly, we studied the active site and proposed a new active site structure for the …


Electrolyte Tailoring For Electrocatalytic Reduction Of Stable Molecules, Jin-Han Li, Fang-Yi Cheng Aug 2020

Electrolyte Tailoring For Electrocatalytic Reduction Of Stable Molecules, Jin-Han Li, Fang-Yi Cheng

Journal of Electrochemistry

Reduction of stable molecules such as CO2 and N2 is important process in electrochemical energy conversion and storage technologies for electrofuels production. However, for the inert nature of CO2/N2 molecule and competitive proton reduction in conventional aqueous electrolytes, selective electrochemical carbon/nitrogen fixation suffers from high overpotential, low reaction rate and low selectivity. While addressing these issues has witnessed substantial advances in electrocatalysts, much less attention has been placed on the electrolytes, which play an important role in regulating the local environment and thus the performance of catalysts under operating conditions. Rational design of electrolytes has …


Recent Progress On Enhancing Effect Of Nanosized Metals For Electrochemical Co2 Reduction, Yu-Ning Zhang, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang Aug 2020

Recent Progress On Enhancing Effect Of Nanosized Metals For Electrochemical Co2 Reduction, Yu-Ning Zhang, Dong-Fang Niu, Shuo-Zhen Hu, Xin-Sheng Zhang

Journal of Electrochemistry

The electrochemical conversion of CO2 to chemical raw material for further utilization shows promising future to alleviate global warming and realize carbon cycle in nature, which is of great significance to the green chemistry and sustainable development. This review briefly introduces the advantages of CO2 electrochemical reduction (CO2ER) and its basic reaction principles, and summarizes the recent progress in a series of activity enhancement strategies based on nanosized metal catalysts. The influences of alloy effect, interface engineering, synergistic effect, surface defect engineering and support effect on the catalytic performance of nanosized metals for CO2ER …


Electromagnetic Interference Reduction Of High-Speed Digital And Analog Circuits Using Engineered Electromagnetic Bandgap Structures, Brandon Ramos Aug 2020

Electromagnetic Interference Reduction Of High-Speed Digital And Analog Circuits Using Engineered Electromagnetic Bandgap Structures, Brandon Ramos

Undergraduate Research Journal

In this paper, we will discuss the concerns of a microstrip two patch antenna system. Coupling of the two-port system can be miniaturized using Electromagnetic Bandgap Structures (EBG) or Defected Ground Structures (DGS) centered between the two patch antennas half a wavelength in size. Different miniaturization methods were used in the design of the antenna system to change the properties of the signal. Changing via locations that are not found on EBG strips themselves, rather found on interleaved ledges between EBG strips allowed for further change in shifting the signals frequency.


Recent Advancement In Pseudo-Random Binary Sequence Signals-Based Fast Reconstruction Of Impedance Spectrum And Its Applications In Electrochemical Energy Sources, Wei-Heng Li, Qiu-An Huang, Wei-Ming Yang, Chang-Ping Yang, Jiu-Jun Zhang Jun 2020

Recent Advancement In Pseudo-Random Binary Sequence Signals-Based Fast Reconstruction Of Impedance Spectrum And Its Applications In Electrochemical Energy Sources, Wei-Heng Li, Qiu-An Huang, Wei-Ming Yang, Chang-Ping Yang, Jiu-Jun Zhang

Journal of Electrochemistry

With the extensive application of impedance spectroscopy, the time-consuming issue of its traditional testing methods has become more and more serious, which limits its application range. In the study of accelerating impedance measurement or reconstruction, the synthesis of wideband excitation signals and the design of high efficiency estimation algorithms have been identified as important ways. In view of the purpose of rapid impedance reconstruction, Pseudo-Random Binary Sequence (PRBS) has the advantages of flat power spectrum and easy generation, and has a good application prospect. This paper reviews three core issues in rapid reconstruction of impedance spectrum: PRBS signal types, different …


Poly(Ethylene Oxide) Based Polymer Electrolytes For All-Solid-State Li-S Batteries, Xue Li, Zheng-Liang Gong Jun 2020

Poly(Ethylene Oxide) Based Polymer Electrolytes For All-Solid-State Li-S Batteries, Xue Li, Zheng-Liang Gong

Journal of Electrochemistry

In recent years, research on lithium-sulfur (Li-S) batteries has received much attention because the sulfur positive electrode and the lithium metal negative electrode produce a high theoretical specific capacity (lithium metal ~ 3800 mAh·g-1, sulfur ~ 1675 mAh·g-1). In addition, sulfur is considered to be the most promising cathode material for secondary lithium batteries, due to its advantages of low price and environmental friendly. However, the practical application of conventional liquid Li-S batteries is still obstructed by several critical issues, such as lithium ploysulfides shuttle effect, long-term stability of lithium metal anode with organic liquid electrolytes, and the safety concerns …


Ordered Mesoporous Carbon/Graphene/Nickel Foam For Flexible Dopamine Detection With Ultrahigh Sensitivity And Selectivity, Lai-Yu Wang, Xin Xi, Dong-Qing Wu, Xiong-Yu Liu, Wei Ji, Rui-Li Liu Jun 2020

Ordered Mesoporous Carbon/Graphene/Nickel Foam For Flexible Dopamine Detection With Ultrahigh Sensitivity And Selectivity, Lai-Yu Wang, Xin Xi, Dong-Qing Wu, Xiong-Yu Liu, Wei Ji, Rui-Li Liu

Journal of Electrochemistry

Flexible biosensors have received intensive attentions for their potential applications in wearable electronics. To obtain flexible electrochemical dopamine (DA) sensors, the ordered mesoporous carbon/graphene/nickel foam (OMC/G/Ni) composite was fabricated in this work via the growth of graphene on Ni foam by chemical vapor deposition, and the formation of the OMC layer followed by the carbonization of co-assembled resol and block polymer., The monolithic Ni foam in the resultant OMC/G/Ni electrode provided an interconnected metal framework with high conductivity and good flexibility, while the OMC layer with the vertically aligned mesopore arrays rendered the composite a large electroactive surface with highly …


Preparation Of Α-Hydroxylated Acetal From 2-Butanone By Indirect Electrooxidation, Hai-Qing Huang, Ye Miao, Xin-Sheng Zhang Jun 2020

Preparation Of Α-Hydroxylated Acetal From 2-Butanone By Indirect Electrooxidation, Hai-Qing Huang, Ye Miao, Xin-Sheng Zhang

Journal of Electrochemistry

Acetoin (3-hydroxy-2-butanone) is an important food spice. As a platform compound, it is widely used in medicine, tobacco, cosmetics, chemical material and other industries. In this paper, α-hydroxylated acetal, an intermediate of acetoin, was prepared from 2-butanone by indirect electrooxidation in the plate and frame electrolytic cell, in which graphite plates were used as both an anode and a cathode, while KOH as an electrolyte and KI as a catalyst. Acetoin could be prepared by hydrolysis in acidic aqueous solution from acetoin intermediate. The effects of current density, electrolyte flow rate between the plates, 2-butanone concentration and electrolysis temperature …