Engineering Commons^™

Modeling And Performance Analysis Of Solid Oxide Fuel Cell, Mariya Pecherskaya, Khakimjan Butanov, Suhrob A. Ibodullaev, Olim Ruzimuradov, Shavkat Mamatkulov

CHEMISTRY AND CHEMICAL ENGINEERING

A three-dimensional numerical model of the system configurations of various types of solid oxide fuel cells (SOFCs) is used and the effect of parameters on SOFC performance is numerically investigated using COMSOL Multiphysics. The effect of parameters such as support layer thickness, operating temperature, and electrode porosity are shown in the polarization and power curves for each model. The results of the study showed the advantages of the anode-supported SOFC compared to cathode- and electrolyte-supported SOFC.

Theoretical calculations demonstrate the highest output power density in the anode-supported SOFC at 900 ℃, and reach a value of 0.585 W cm^{-2 …}

Quest For An Optimal Spin-Polarized Electron Source For The Electron-Ion Collider, J. Biswas, E. Wang, O. Rahman, J. Sharitka, K. Kisslinger, Adam Masters, S. Marsillac, T. Lee

Electrical & Computer Engineering Faculty Publications

Superlattice GaAs photocathodes play a crucial role as the primary source of polarized electrons in various accelerator facilities, including the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson National Laboratory and the Electron-Ion Collider (EIC) at Brookhaven National Laboratory. To increase the quantum efficiency (QE) of GaAs/GaAsP superlattice photocathodes, a Distributed Bragg Reflector (DBR) is grown underneath using metal-organic chemical vapor deposition (MOCVD). There are several challenges associated with DBR photocathodes: the resonance peak may not align with the emission threshold of around 780 nm, non-uniform doping density in the top 5 nm may significantly impact QE and spin polarization, …

Factors Affecting Electrocoagulation Process For Different Water Types: A Review, Shahad Fadhil Abed Al-Rubaye, Naseer A. Alhaboubi, Aiman H. Al-Allaq

Mechanical & Aerospace Engineering Faculty Publications

Raw water must meet specific physical, chemical, and biological requirements to be suitable for drinking. There are various techniques available for treating wastewater, and aside from conventional methods that involve chemicals, electrocoagulation is an efficient and advanced approach. Electrocoagulation has proven effective in treating many pollutants, including bacteria, viruses, iron, fluoride, sulfate, boron, hardness, and turbidity. Total suspended solids, organic and inorganic materials, chemical oxygen demand COD, biochemical oxygen demand BOD, and color. It finds extensive application in treating different types of water and wastewater due to its exceptional ability to remove diverse contaminants. Recently, electrocoagulation has garnered significant attention …

Battery Design, Construction, And Characterization For Small Motor Use Focusing On Anodic Zinc For Electron Flow, Amber Veach

Chemical Engineering Undergraduate Honors Theses

This thesis explores the construction, characterization, and application of anodic zinc batteries for powering a small electric motor for the ChemE Car competition. Two zinc galvanic cell batteries were studied: zinc-carbon and zinc-air batteries. Prototype batteries were constructed and tested for voltage, amperage, and power production. In the zinc-carbon trials, a 3:1 mixture of manganese dioxide and graphite was determined to be the best cathode for power production. The size which allowed for sufficient power while maintaining the smallest footprint on the car was a zinc can six cm tall and two cm in diameter. Analysis of paper zinc-air battery …

Comparison Of Layered Nickel Cobalt Manganese Oxide Cathodes With Different Compositions And Morphologies In Lithium-Ion Batteries, Fanny Poon

Electronic Thesis and Dissertation Repository

The revolutionary rechargeable lithium-ion battery paves the way for environmentally-friendly applications such as electric vehicles. Nevertheless, further improvements are required to match or exceed the performance of conventional internal combustion engine vehicles, such as higher energy density, faster charging speed, longer lifetime, better safety and lower cost. Lithium layered nickel cobalt manganese oxides (NCM) are a popular choice of cathode material, but they still suffer from problems such as cation mixing, volume changes, microcracking, surface side reactions, high temperature performance issues and structural reconstruction. This thesis compares various NCM materials to figure out what guidelines should be followed to improve …

Structural Degradation Of Ni-Rich Layered Oxide Cathode For Li-Ion Batteries, Jia-Yi Wang, Sheng-Nan Guo, Xin Wang, Lin Gu, Dong Su

Journal of Electrochemistry

Nickel(Ni)-rich layered oxide has been regarded as one of the most important cathode materials for the lithium-ion batteries because of its low cost and high energy density. However, the concerns in safety and durability of this compound are still challenging for its further development. On this account, the in-depth understanding in the structural factors determining its capacity attenuation is essential. In this review, we summarize the recent advances on the degradation mechanisms of Ni-rich layered oxide cathode. Progresses in the structure evolution of Ni-rich oxide are carefully combed in terms of inner evolution, surface evolution, and the property under thermal …

Structure Analysis Of Pemfc Cathode Catalyst Layer, Rui-Qing Wang, Sheng Sui

Journal of Electrochemistry

The sluggish oxygen reduction reaction (ORR) on the cathode of the proton exchange membrane fuel cell (PEMFC) has always been one of the key factors limiting its commercialization. The optimization of the cathode catalytic layer structure plays an important role in improving fuel cell performance and reducing production costs. In this paper, two different catalysts (platinum nanoparticles (Pt-NPs) and platinum nanowires (Pt-NWs)) were prepared by using catalyst coated substrate (CCS) method. By constructing a double-layer catalytic layer structure, we analyzed the effect of different catalytic layer structures by performing a single cell test. The results showed that the dense platinum …

Nitro Group Reduction For Use In Organic, Cathodic Materials, Brock G. Goeden

Honors Thesis

The industrial demand for higher capacity, light-weight battery materials has skyrocketed in recent years due to heavy investments in portable electronics, electronic vehicles, and renewable energy sources. However, rechargeable battery technology has seen little improvement since the invention of the Lithium-Ion battery in the 1980s. The low energy density of the traditionally utilized LiCoO2 cathodic material (specific capacity: 272 mAh g-1), has limited its potential to meet these increasing demands. To solve this problem, our research group is investigating new types of lightweight, organic, polymeric materials with conductive backbones as a possible replacement for the cathodic materials in Lithium-Ion batteries. …

Enhanced Electrochemical Performance Of Li-Ion Battery Cathodes By Atomic Layer Deposition, Yan Gao

Doctoral Dissertations

”Li-ion battery now plays an irreplaceable role in supplying green and convenient energy. In this work, atomic layer deposition (ALD) was used to modify Li-ion battery cathode particles for performance enhancement.

An ultrathin and conductive CeO₂ ALD film was deposited on Li-rich layered cathode particles, of which the specific capacity and cyclic stability were significantly improved. On the same cathode particles, FeO_x ALD and post-annealing resulted in a stable and conductive surface spinel phase to improve the performance.

Synergetic TiN coating and Ti doping were performed on a LiFePO₄ (LFP) cathode and extended its cycle life. The …

P2-Type Na2/3ni1/3mn2/3o2as A Cathode Materialwith High-Rate And Long-Life For Sodium Ionstorage, Qiannan Liu, Zhe Hu, Mingzhe Chen, Chao Zou, Huile Jin, Shun Wang, Qinfen Gu, Shulei Chou

Australian Institute for Innovative Materials - Papers

Layered P2-type Na 2/3 Ni 1/3 Mn 2/3 O 2 was successfully synthesized through a facile sol-gel method and subsequent heat treatment. Resulting from different phase transformation and sodium ion diffusion rates, its electrochemical performance is highly related to the cut-off voltage and the electrolyte used. When the cut-off voltage is set up to 4.5 V or lowered to 1.5 V, capacity fade happens due to the occurrence of P2-O2 transformation and electrolyte decomposition or the redox reaction of the Mn 4+ /Mn 3+ ionic pair and P2-P2′ transformation. The electrode maintained 89.0 mA h g -1 with good cycling …

Structure And Electrochemical Performance Modulation Of A Lini0.8co0.1mn0.1o2 Cathode Material By Anion And Cation Co-Doping For Lithium Ion Batteries, Rong Li, Yong Ming, Wei Xiang, Chunliu Xu, Guilin Feng, Yongchun Li, Yanxiao Chen, Zhenguo Wu, Ben-He Zhong, Xiaodong Guo

Australian Institute for Innovative Materials - Papers

Ni-rich layered transition metal oxides show great energy density but suffer poor thermal stability and inferior cycling performance, which limit their practical application. In this work, a minor content of Co and B were co-doped into the crystal of a Ni-rich cathode (LiNi0.8Co0.1Mn0.1O2) using cobalt acetate and boric acid as dopants. The results analyzed by XRD, TEM, XPS and SEM reveal that the modified sample shows a reduced energy barrier for Li+ insertion/extraction and alleviated Li+/Ni2+ cation mixing. With the doping of B and Co, corresponding enhanced cycle stability was achieved with a high capacity retention of 86.1% at 1.0C …

Research Progresses In Improvement For Low Temperature Performance Of Lithium-Ion Batteries, Yue-Ru Gu, Wei-Min Zhao, Chang-Hu Su, Chuan-Jun Luo, Zhong-Ru Zhang, Xu-Jin Xue, Yong Yang

Journal of Electrochemistry

Lithium-ion batteries (LIBs) have become a new research hotspot due to their high energy density and long service life. However, the temperature characteristics, especially the poor performance at low temperatures, have seriously limited their wider applications. In this report, the research progresses in the low temperature performance of LIBs are reviewed. The main existing limitations of LIBs at low temperatures were systematically analyzed, and followed by discussion on the recent improvements in low temperature performances by developing novel cathode, electrolyte, and anode materials. The developments for improving the low temperature performance of LIBs are prospected. The three most important factors …

Electrochemical Behaviors Of The Electrodes For Proton Conducting Intermediate Temperature Solid Oxide Fuel Cells (It-Sofc), Shichen Sun

FIU Electronic Theses and Dissertations

Proton conducting intermediate temperature (600oC-400oC) solid oxide fuel cells (IT-SOFC) have many potential advantages for clean and efficient power generation from readily available hydrocarbon fuels. However, it still has many unsolved problems, especially on the anode where the fuel got oxidized and the cathode where oxygen got reduced. In this study, for the anode, the effects of hydrogen sulfite (H2S) and carbon dioxide (CO2) as fuel contaminants were studied on the nickel (Ni) based cermet anode of proton conducting IT-SOFC using proton conducting electrolyte of BaZr0.1Ce0.7Y0.1Yb0.1O3 (BZCYYb). Both low-ppm level H2S and low-percentage level CO2 caused similar poisoning effects on …

A Brief Review Of Conductivity And Thermal Expansion Of Perovskite-Related Oxides For Sofc Cathode, A. V. Nikonov, K. A. Kuterbekov, K. Zh. Bekmyrza, N. B. Pavzderin

Eurasian Journal of Physics and Functional Materials

Cathode materials with mixed ion-electron conductivity (MIEC) are necessary for the development of low or intermediate temperature solid oxide fuel cells. Perovskite and perovskite-related materials are promising candidates on this role. In the review the conductivity and the thermal expansion of materials with various types of perovskite-related structures such as pure perovskite, double perovskite, brownmillerite and Ruddlesden-Popper phases have been compared. And the literature data on the values of the electronic and ionic conductivities, the oxygen diffusion coefficient, and the thermal expansion coefficient of various compositions have been collected. It was shown that the disordered cubic perovskites possess the higher …

Influences Of Na-Mn Ratio On Electrochemical Performances And Intercalation-Deintercalation Processes Of Sodium Ion In NaXMno2, Yong-Chun Xie, Cheng Wang, Fang Jiang, Yang Yang, Jing Su, Yun-Fei Long, Yan-Xuan Wen

Journal of Electrochemistry

In this work, Na_xMnO₂ was synthesized by a solid-state reaction. The influences of Na:Mn ratio on the structure, morphology and electrochemical performance, and sodium ion intercalation/deintercalation processes were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge-discharge test. The prepared Na_xMnO₂ was mainly composed of Na_0.7MnO₂ and Na_0.91MnO₂, and the content of Na_0.91MnO₂ increased with the increase of Na:Mn ratio. However, the activation energy values of surface membrane diffusion, interfacial electrochemical reaction and …

The Catalytic Performance Of Lithium Oxygen Battery Cathodes, Neha Chawla

FIU Electronic Theses and Dissertations

High energy density batteries have garnered much attention in recent years due to their demand in electric vehicles. Lithium-oxygen (Li-O2) batteries are becoming some of the most promising energy storage and conversion technologies due to their ultra-high energy density. They are still in the infancy stage of development and there are many challenges needing to be overcome before their practical commercial application. Some of these challenges include low round-trip efficiency, lower than theoretical capacity, and poor rechargeability. Most of these issued stem from the poor catalytic performance of the cathode that leads to a high overpotential of the battery. In …

Direct Regeneration Of Cathode Materials From Spent Lithium Iron Phosphate Batteries Using A Solid Phase Sintering Method, X Song, T Hu, C Liang, H L. Long, L Zhou, W Song, L You, Z S. Wu, J W. Liu

Australian Institute for Innovative Materials - Papers

A direct regeneration of cathode materials from spent LiFePO4 batteries using a solid phase sintering method has been proposed in this article. The spent battery is firstly dismantled to separate the cathode and anode plate, and then the cathode plate is soaked in DMAC organic solvent to separate the cathode materials and Al foil at optimal conditions of 30 min at 30 °C and solid liquid ratio of 1[thin space (1/6-em)]:[thin space (1/6-em)]20 g ml−1. XRD and SEM results of the spent LiFePO4 after separation show that there are some impurity phase components and irregular morphologies with many agglomerations. The …

Sulfur Based Electrode Materials For Secondary Batteries, Yong Hao

FIU Electronic Theses and Dissertations

Developing next generation secondary batteries has attracted much attention in recent years due to the increasing demand of high energy and high power density energy storage for portable electronics, electric vehicles and renewable sources of energy. This dissertation investigates sulfur based advanced electrode materials in Lithium/Sodium batteries. The electrochemical performances of the electrode materials have been enhanced due to their unique nano structures as well as the formation of novel composites.

First, a nitrogen-doped graphene nanosheets/sulfur (NGNSs/S) composite was synthesized via a facile chemical reaction deposition. In this composite, NGNSs were employed as a conductive host to entrap S/polysulfides in …

Electricity Generation Of Microbial Fuel Cell Using Stainless Steel Mesh As Cathode, Hong-Yan Dai, Hui-Min Yang, Xian Liu, Xuan Jian, Xiu-Li Song, Zhen-Hai Liang

Journal of Electrochemistry

In the present work, a dual-chamber microbial fuel cell (MFC) was constructed with aeration tank sludge as an inoculum, carbon felt as an anode and stainless steel mesh without any modification as a cathode. The influence of the cathode size was investigated in terms of voltage output, power generation and electrochemical impedance. The long-term durability of the stainless steel mesh cathode was also evaluated. Results showed that the stainless steel mesh exhibited satisfactory long-term durability as MFC cathode. When the stainless steel mesh size was 2 × 2 cm², the maximum output voltage, power density, the internal resistance …

Nano-Structured Electrocatalysts For High Performance Lithium Sulfur Batteries, Negar Mosavati

Wayne State University Dissertations

Ni nanoparticles has been investigated as a carbon-free cathode material for dissolved polysulfide Li-S battery. A series of Ni nanoparticles with nominal particle size of 20, 40, and 100 nm have been used as electrocatalysts, and the effect of particle size on Li-S battery performance has been investigated. In addition, graphene has been chosen as a support to anchor the Ni nanoparticles, and the synergetic effect of carbon material and Ni nanoparticles on Li-S battery electrochemical performance has been studied. The results indicated there is a strong particle size effect. Ni/graphene electrode exhibits a capacity of 753 mAh g-1 sulfur …

A Strategy For Configuration Of An Integrated Flexible Sulfur Cathode For High-Performance Lithium-Sulfur Batteries, Hongqiang Wang, Wenchao Zhang, Hua-Kun Liu, Zaiping Guo

Faculty of Engineering and Information Sciences - Papers: Part A

Lithium-sulfur batteries are regarded as promising candidates for energy storage devices owing to their high theoretical energy density. The practical application is hindered, however, by low sulfur utilization and unsatisfactory capacity retention. Herein, we present a strategy for configuration of the sulfur cathode, which is composed of an integrated carbon/sulfur/carbon sandwich structure on polypropylene separator that is produced using the simple doctor-blade technique. The integrated electrode exhibits excellent flexibility and high mechanical strength. The upper and bottom carbon layers of the sandwich-structured electrode not only work as double current collectors, which effectively improve the conductivity of the electrode, but also …

A Methodical Approach For Fabrication Of Binder-Free Li2s-C Composite Cathode With High Loading Of Active Material For Li-S Battery, Mohammad Kaiser, Xin Liang, Hua-Kun Liu, S X. Dou, Jiazhao Wang

Australian Institute for Innovative Materials - Papers

Lithium sulfide (Li2S), which has a theoretical capacity of 1166 mA h/g, is considered as a promising cathode material for the Li-S battery. The electrochemical performance of microsized Li2S is impaired, however, by its low electrical conductivity as well as first cycle high activation potential problem. In this work, microsized Li2S powder had been ball-milled with different carbon sources to synthesize Li2S-C composites as well as to find the suitable carbon sources, which were then capillary-deposited in three-dimensional multi-layered Ni foam from a dioxolane-containing mixture to fabricate a binder-free Li2S-C composite cathode. A large amount of active material (∼5 mg/cm2) …

Nanostructured Materials Prepared By Atomic Layer Deposition For Catalysis And Lithium-Ion Battery Applications, Rajankumar Patel

Doctoral Dissertations

"Atomic/molecular layer deposition (ALD/MLD) has emerged as an important technique for depositing thin films in both scientific research and industrial applications. In this dissertation, ALD/MLD was used to create novel nanostructures for two different applications, catalysis and lithium-ion batteries.

MLD was used to prepare ultra-thin dense hybrid organic/inorganic polymer films. Oxidizing the hybrid films removed the organic components and produced the desired nanoporous films. Both porous alumina and titania films can be prepared by such a way. A novel nanostructured catalyst (Pt/SiO₂) with an ultra-thin porous alumina shell obtained from the thermal decomposition of an aluminium alkoxide film …

A High-Performance Rechargeable Mg2+/Li+ Hybrid Battery Using One-Dimensional Mesoporous Tio2(B) Nanoflakes As The Cathode, Shuojian Su, Yanna Nuli, Zhenguo Huang, Qi Miao, Jun Yang, Jiulin Wang

Australian Institute for Innovative Materials - Papers

Mg2+/Li+ hybrid batteries have recently been constructed combining a Mg anode, a Li+-intercalation electrode, and an electrolyte containing both Mg2+ and Li+. These batteries have been reported to outperform all the previously reported magnesium batteries in terms of specific capacity, cycling stability, and rate capability. Herein, we report the outstanding electrochemical performance of Mg2+/Li+ hybrid batteries consisting of a one-dimensional mesoporous TiO2(B) cathode, a Mg anode, and an electrolyte consisting of 0.5 mol L-1 Mg(BH4)2 + 1.5 mol L-1 LiBH4 in tetraglyme. A highly synergetic interaction between Li+ and Mg2+ ions toward the pseudo-capacitive reaction is proposed. The hybrid batteries …

A Platinum Nanowire Network As A Highly Effective Current Collector For Intermediate Temperature Solid Oxide Fuel Cells, Hanping Ding, Xingjian Xue

Xingjian "Chris" Xue

We report the fabrication and evaluation of a platinum nanowire network as a highly efficient current collector for solid oxide fuel cells (SOFCs). The ink of carbon-black supported platinum nanoparticles was sprayed onto the cathode. After firing, the carbon black was oxidized and disappeared as carbon dioxide gas while the platinum nanoparticles connect with one another, forming a tree-branch-like nanowire network. The diameters of the nanowires range from 100 nm to 400 nm. Compared to a conventional platinum paste current collector, the polarization resistance of the PrBaCo₂O_5+δ (PBCO) cathode with a nanowire current collector was reduced …

A Platinum Nanowire Network As A Highly Effective Current Collector For Intermediate Temperature Solid Oxide Fuel Cells, Hanping Ding, Xingjian Xue

Xingjian "Chris" Xue

We report the fabrication and evaluation of a platinum nanowire network as a highly efficient current collector for solid oxide fuel cells (SOFCs). The ink of carbon-black supported platinum nanoparticles was sprayed onto the cathode. After firing, the carbon black was oxidized and disappeared as carbon dioxide gas while the platinum nanoparticles connect with one another, forming a tree-branch-like nanowire network. The diameters of the nanowires range from 100 nm to 400 nm. Compared to a conventional platinum paste current collector, the polarization resistance of the PrBaCo2O5+δ (PBCO) cathode with a nanowire current collector was reduced by 44% at 650 …

Research Progress In Carbon Coating On Lifepo4 Cathode Materials For Lithium Ion Batteries, Ning Zhang, Yong-Chang Liu, Cheng-Cheng Chen, Zhi-Qiang Zhu, Zhan-Liang Tao, Jun Chen

Journal of Electrochemistry

Olivine-structured LiFePO₄ has been received much attention because of its flat voltage profile, low cost, abundant material supply and better environmental compatibility. However, the poor electronic and ionic conductivities have limited its application in industry. One of the best methods to improve the electrochemical performance is carbon coating. In this review, we summarize the recent developments of LiFePO₄/C cathode. Moreover, the different effects caused by coating methods and carbon sources, as well as the mechanism of carbon coating on the properties of LiFePO₄/C are reviewed.

Current Status And Prospect Of Cathode Materials For Lithium Sulfur Batteries, Lan Zhou, Ai-Shui Yu

Journal of Electrochemistry

Elemental sulfur has been extensively investigated as a promising candidate of cathode material for next generation lithium secondary batteries. However, some troublesome issues, such as the low electric conductivity of sulfur (5×10^-30 S·cm^-1) and the high solubility of lithium polysulfide intermediates in organic electrolytes, resulting in a low utilization of active material and a redox shuttling of dissolved polysulfide ions between the sulfur cathode and the lithium anode, which eventually leads to a deposition of insoluble and insulating Li₂S₂/Li₂S on the electrode surface and a fast reduction in the specific capacity. …

La0.7Sr0.3Fe0.7Ga0.3O3-Δ As Electrode Material For A Symmetrical Solid Oxide Fuel Cell, Zhibin Yang, Yu Chen, Chao Jin, Guoliang Xiao, Minfang Han, Fanglin Chen

Fanglin Chen

In this research, La_0.7Sr_0.3Fe_0.7Ga_0.3O_3−δ (LSFG) perovskite oxide was successfully prepared using a microwave-assisted combustion method, and employed as both anode and cathode in symmetrical solid oxide fuel cells. A maximum power density of 489 mW cm⁻² was achieved at 800 °C with wet H₂ as the fuel and ambient air as the oxidant in a single cell with the configuration LSFG|La_0.8Sr_0.2Ga_0.83Mg_0.17O_3−δ|LSFG. Furthermore, the cells demonstrated good stability in H₂ and acceptable sulfur tolerance.

Cathode Polarizations Of A Cathode-Supported Solid Oxide Fuel Cell, Kevin Huang, Alessandro Zampieri, Martin Ise

Kevin Huang

The concentration, activation, and total polarizations of the cathode in a cathode-supported solid oxide fuel cell (SOFC) were theoretically and experimentally investigated. In the theoretical analysis, the exchange current density of the charge transfer was considered to be dependent on the PO2 determined by the preceding O2 diffusion, resulting in an interrelationship between activation and concentration polarizations. The established nonlinear polarization equations were then applied to solve the key parameters with area specific resistances and overpotentials of the polarizations experimentally measured by electrochemical impedance spectroscopy on an operating cathode-supported SOFC. To ensure the consistency and meaningfulness of the solutions, the …