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Full-Text Articles in Engineering

Segmentation Of Intracranial Structures From Noncontrast Ct Images With Deep Learning, Evan Porter Jan 2022

Segmentation Of Intracranial Structures From Noncontrast Ct Images With Deep Learning, Evan Porter

Wayne State University Dissertations

Presented in this work is an investigation of the application of artificially intelligent algorithms, namely deep learning, to generate segmentations for the application in functional avoidance radiotherapy treatment planning. Specific applications of deep learning for functional avoidance include generating hippocampus segmentations from computed tomography (CT) images and generating synthetic pulmonary perfusion images from four-dimensional CT (4DCT).A single institution dataset of 390 patients treated with Gamma Knife stereotactic radiosurgery was created. From these patients, the hippocampus was manually segmented on the high-resolution MR image and used for the development of the data processing methodology and model testing. It was determined that …


Electrochemical Gelation Of Metal Chalcogenide Quantum Dots, Chathuranga Chinthana Hewa Rahinduwage Jan 2022

Electrochemical Gelation Of Metal Chalcogenide Quantum Dots, Chathuranga Chinthana Hewa Rahinduwage

Wayne State University Dissertations

Quantum dots (QDs) are attractive because of their unique size-dependent optical and electronic properties and high surface area. They are tested in research for diverse applications, including energy conversion, catalysis, and sensing. Assembling QDs into functional solid-state devices while preserving their attractive properties is a challenge. Methods currently under the research are not effective in directly fabricating QDs onto devices, making large area assemblies, maintaining the high surface area by forming 3D porous structures, and conducting electricity for applications such as sensing. QD gels are an example of QD assemblies that consist of a 3D porous interconnected QD network. They …


Optical Signal Processing With Discrete-Space Metamaterials, Mohammad Moein Moeini Jan 2022

Optical Signal Processing With Discrete-Space Metamaterials, Mohammad Moein Moeini

Wayne State University Dissertations

As digital circuits are approaching the limits of Moore’s law, a great deal of efforthas been directed to alternative computing approaches. Among them, the old concept of optical signal processing (OSP) has attracted attention, revisited in the light of metamaterials and nano-photonics. This approach has been successful in realizing basic mathematical operations, such as derivatives and integrals, but it is difficult to be applied to more complex ones. Inspired by digital filters, we propose a radically new OSP approach, able to realize arbitrary mathematical operations over a nano-photonic platform. We demonstrate this concept for the case of spatial differentiation, image …


High Mobility N-Type Field Effect Transistors Enabled By Wse2/Pdse2 Heterojunctions, Arthur Bowman Iii Jan 2021

High Mobility N-Type Field Effect Transistors Enabled By Wse2/Pdse2 Heterojunctions, Arthur Bowman Iii

Wayne State University Dissertations

Two-dimensional (2D) semiconductors such as transition metal dichalcogenides (TMDs) have emerged as a promising candidate for post-silicon electronics. Few-layer tungsten diselenide (WSe2), a well-studied TMD, has sown high hole mobility and ON/OFF ratio in field effect transistor (FET) devices. But the n-type performance of WSe2 is still quite limited by the presence of a substantial Schottky Barrier. Palladium diselenide, (PdSe2) is a newly discovered TMD that is of interest because of its high electron mobility, and moderate ON/OFF ratios. However, despite its relatively small bandgap, the n-type performance of few-layer PdSe2 FETs has also been limited by a Schottky barrier, …


Software As A Service: The Mediating Role Of Consequences Of Saas Diffusion On Firm Performance, Cristina Marie-Mccarthy Recchia Jan 2021

Software As A Service: The Mediating Role Of Consequences Of Saas Diffusion On Firm Performance, Cristina Marie-Mccarthy Recchia

Wayne State University Dissertations

ABSTRACTSOFTWARE AS A SERVICE: THE MEDIATING ROLE OF CONSEQUENCES OF SAAS DIFFUSION ON FIRM PERFORMANCE by CRISTINA MARIE-MCCARTHY RECCHIA DECEMBER 2021 Advisor: Dr. Ratna Babu Chinnam Major: Industrial Engineering Degree: Doctor of Philosophy There are ample studies that support a positive link between information technology and firm performance. Bharadwaj (2000) and Chae (2014, 2018) are two examples that provided a foundation for this work. These scholars looked at how capabilities associated with information technology contribute to improved financial performance using a specific set of financial ratios. In addition, there are studies that examine a positive link between Software-as-a-Service (SaaS) and …


Improved Contacts And Device Performance In Mos2 Transistors Using 2d Semiconductor Interlayers, Kraig Andrews Jan 2020

Improved Contacts And Device Performance In Mos2 Transistors Using 2d Semiconductor Interlayers, Kraig Andrews

Wayne State University Dissertations

The rapid growth of modern electronics industry over the past half-century has been sustained by the continued miniaturization of silicon-based electronics. However, as fundamental limits approach, there is a need to search for viable alternative materials for next-generation electronics in the post-silicon era. Two-dimensional (2D) semiconductors such as transition metal dichalcogenides (TMDs) have attracted much attention due to their atomic thickness, absence of dangling bonds and moderately high carrier mobility. However, achieving low-resistance contacts has been major impediment in developing high-performance field-effect transistors (FETs) based on 2D semiconductors. A substantial Schottky barrier (SB) is often present at the metal/2D-semicondcutor interface, …


Ac Conductivity Studies Of Polyethylene-Oxide-Garnet Type Li7la3zr2o12 Hybrid Composite Solid Polymer Electrolyte For Li-Ion Battery, Parisa Bashiri Jan 2020

Ac Conductivity Studies Of Polyethylene-Oxide-Garnet Type Li7la3zr2o12 Hybrid Composite Solid Polymer Electrolyte For Li-Ion Battery, Parisa Bashiri

Wayne State University Dissertations

Solid electrolytes including ceramics and polymers are considered to be the ultimate substitute for organic liquid electrolytes currently used in commercialized lithium ion batteries to address the safety concerns due to Li dendrite growth and internal short circuiting. However, low ionic conductivity due to high grain boundary resistance in ceramics and semi-crystalline nature of polymers has held back the solid electrolytes from being used in Li-ion batteries. Polyethylene oxide (PEO), complexed with a Li-salt, is a well-studied polymer electrolyte showing ionic conductivity properties at room temperature. However, the coexistence of amorphous and crystalline regions at room temperature (< Tm, the melting temperature) has

-8 -6 …


Study Of Grain Growth In Single-Phase Polycrystals, Pawan Vedanti Jan 2020

Study Of Grain Growth In Single-Phase Polycrystals, Pawan Vedanti

Wayne State University Dissertations

Materials with random microstructure are characterized by additional thermodynamic parameters, entropy and temperature of microstructure. It has been argued that there is one more law of thermodynamics: entropy of microstructure decays in isolated systems. This assertion has been checked experimentally for the process of grain growth which showed that entropy of grain structure decays indeed as expected. The equation of state for microstructure entropy has also been studied. In general, entropy of grain microstructure is expected to be a function of grain structure energy and the average grain size. Our experiments suggest that in fact, the equation of state degenerates …


Incorporating Cardiac Substructures Into Radiation Therapy For Improved Cardiac Sparing, Eric Daniel Morris Jan 2020

Incorporating Cardiac Substructures Into Radiation Therapy For Improved Cardiac Sparing, Eric Daniel Morris

Wayne State University Dissertations

Growing evidence suggests that radiation therapy (RT) doses to the heart and cardiac substructures (CS) are strongly linked to cardiac toxicities, though only the heart is considered clinically. This work aimed to utilize the superior soft-tissue contrast of magnetic resonance (MR) to segment CS, quantify uncertainties in their position, assess their effect on treatment planning and an MR-guided environment.

Automatic substructure segmentation of 12 CS was completed using a novel hybrid MR/computed tomography (CT) atlas method and was improved upon using a 3-dimensional neural network (U-Net) from deep learning. Intra-fraction motion due to respiration was then quantified. The inter-fraction setup …


Data-Driven Intelligent Scheduling For Long Running Workloads In Large-Scale Datacenters, Guoyao Xu Jan 2019

Data-Driven Intelligent Scheduling For Long Running Workloads In Large-Scale Datacenters, Guoyao Xu

Wayne State University Dissertations

Cloud computing is becoming a fundamental facility of society today. Large-scale public or private cloud datacenters spreading millions of servers, as a warehouse-scale computer, are supporting most business of Fortune-500 companies and serving billions of users around the world. Unfortunately, modern industry-wide average datacenter utilization is as low as 6% to 12%. Low utilization not only negatively impacts operational and capital components of cost efficiency, but also becomes the scaling bottleneck due to the limits of electricity delivered by nearby utility. It is critical and challenge to improve multi-resource efficiency for global datacenters.

Additionally, with the great commercial success of …


Spectral Methods For Hamiltonian Systems And Their Applications, Lewei Zhao Jan 2019

Spectral Methods For Hamiltonian Systems And Their Applications, Lewei Zhao

Wayne State University Dissertations

Hamiltonian systems typically arise as models of conservative physical systems and have many applications. Our main emphasis is using spectral methods to preserve both symplectic structure and energy up to machine error in long time. An engery error estimation is given for a type of Hamiltonian systems with polynomial nonlinear part, which is numerical verified by solving a Henon-Heiles systems. Three interesting applications are presented : the first one is the N-body problems. The second one is approximation for Weyl's Law and the third one is simulating quantum cooling in an optomechanical system to study the dissipative dynamics. Moreover, nonsmooth …


Rare-Earth-Activated Group Vi D0 Metal Oxides As Thermosensitive Phosphors, Samarage Sameera Perera Jan 2019

Rare-Earth-Activated Group Vi D0 Metal Oxides As Thermosensitive Phosphors, Samarage Sameera Perera

Wayne State University Dissertations

ABSTRACT

RARE-EARTH-ACTIVATED GROUP VI d0 METAL OXIDES AS

THERMOSENSITIVE PHOSPHORS

by

SAMARAGE SAMEERA PRASAD PERERA

AUGUST 2019

Advisor: Dr. Federico A. Rabuffetti

Major: Chemistry

Degree: Doctor of Philosophy

Thermosensitive phosphors are solid-state materials that demonstrate distinct dependence of luminescence emission on temperature. These materials enable optical temperature sensing in environments where conventional thermometry is not possible (e.g., gas turbines, combustion engines, surface temperature distributions). However, the design of thermosensitive phosphors that show adequate sensitivity and low thermal quenching in the intermediate temperature range (i.e., 500–1000 K) remains challenging. This challenge can be addressed by understanding how to rationally manipulate the …


Fundamental Insights On The Electrolysis Of Co2 Using Solid Oxide Electrolysis Cells, Juliana Silva Alves Carneiro Jan 2019

Fundamental Insights On The Electrolysis Of Co2 Using Solid Oxide Electrolysis Cells, Juliana Silva Alves Carneiro

Wayne State University Dissertations

The work reported in this thesis focused on providing a fundamental understanding, at the molecular level, required to guide the effective design of electrocatalysts towards a superior reaction kinetics on the electrode of solid oxide electrolysis cells SOECs devices (SOECs) during the CO2 electrolysis. High temperature SOECs are electrochemical energy conversion technologies, that have emerged as promising alternatives to mitigate environmental issues associated with combustion-based technologies, such as the rising atmospheric CO2 levels. The conversion of excess CO2 into high-energy molecules, such as CO can be efficiently achieved through the use of SOEC – which facilitates the electrochemical reduction of …


Mixture Models With Grouping Structure: Retail Analytics Applications, Haidar Almohri Jan 2018

Mixture Models With Grouping Structure: Retail Analytics Applications, Haidar Almohri

Wayne State University Dissertations

Growing competitiveness and increasing availability of data is generating tremendous interest in data-driven analytics across industries. In the retail sector, stores need targeted guidance to improve both the efficiency and effectiveness of individual stores based on their specific location, demographics, and environment. We propose an effective data-driven framework for internal benchmarking that can lead to targeted guidance for individual stores. In particular, we propose an objective method for segmenting stores using a model-based clustering technique that accounts for similarity in store performance dynamics. It relies on effective Finite Mixture of Regression (FMR) techniques for carrying out the model-based clustering with …


Integrated Strategies For Sustainable Wastewater-Based Algal Biofuel Production And Environmental Mitigation In The Us, Javad Roostaei Jan 2018

Integrated Strategies For Sustainable Wastewater-Based Algal Biofuel Production And Environmental Mitigation In The Us, Javad Roostaei

Wayne State University Dissertations

Integration of algae cultivation with wastewater treatment has received increasing interest as a cost-effective strategy for biofuel production. However, there has been no full assessment of algal biofuel production with wastewater on macro-scale by taking into account wastewater resources, land availability, CO2 emission resources, and geographic variation. This research addressed and evaluated the use of wastewater for algae cultivation, in terms of modeling and laboratory experiments. The first goal of this research was to develop a spatially explicit lifecycle model, by integrating life cycle assessment (LCA), and Geographic Information Systems (GIS) analysis, for the evaluation of the environmental and economic …


Synthesis Of Volatile And Thermally Stable Aluminum Hydride Complexes And Their Use In Atomic Layer Deposition Of Metal Thin Films, Kyle Blakeney Jan 2018

Synthesis Of Volatile And Thermally Stable Aluminum Hydride Complexes And Their Use In Atomic Layer Deposition Of Metal Thin Films, Kyle Blakeney

Wayne State University Dissertations

The research discussed in this dissertation spans both synthetic inorganic and nanomaterials chemistry. Aluminum hydride complexes have been synthesized and characterized which are highly volatile and thermally stable and their potential as reducing agents for ALD of electropositive metal and metal-containing films was evaluated. A major discovery has been the deposition of aluminum metal films by thermal ALD using an aluminum dihydride complex supported by a simple amido-amine ligand (Chapters 2). Aluminum is the most electropositive element deposited by purely thermal ALD to date and represents a significant breakthrough for this field. This process may have important industrial applications and …


Data-Driven Modeling For Decision Support Systems And Treatment Management In Personalized Healthcare, Milad Zafar Nezhad Jan 2018

Data-Driven Modeling For Decision Support Systems And Treatment Management In Personalized Healthcare, Milad Zafar Nezhad

Wayne State University Dissertations

Massive amount of electronic medical records (EMRs) accumulating from patients and populations motivates clinicians and data scientists to collaborate for the advanced analytics to create knowledge that is essential to address the extensive personalized insights needed for patients, clinicians, providers, scientists, and health policy makers. Learning from large and complicated data is using extensively in marketing and commercial enterprises to generate personalized recommendations. Recently the medical research community focuses to take the benefits of big data analytic approaches and moves to personalized (precision) medicine. So, it is a significant period in healthcare and medicine for transferring to a new paradigm. …


Carbazole Based Multifunctional Dopamine Agonists And Related Molecules As Potential Symptomatic And Disease Modifying Therapeutic Agents For Parkinson’S Disease, Asma S.Mohamed Elmabruk Jan 2018

Carbazole Based Multifunctional Dopamine Agonists And Related Molecules As Potential Symptomatic And Disease Modifying Therapeutic Agents For Parkinson’S Disease, Asma S.Mohamed Elmabruk

Wayne State University Dissertations

Parkinson’s disease (PD) is a progressive neurodegenerative disease that develops from gradual depletion of dopamine (DA) and dopaminergic neurons in the substantia nigra pars compacta (SNc) with the accumulation of intraneuronal proteinaceous matter named as Lewy bodies. The four cardinal symptoms associated with PD are tremor, rigidity, bradykinesia, and postural instability. Although the exact mechanism and etiology of PD are not fully understood, several factors have been implicated in the pathogenesis and progression of PD including protein aggregation, oxidative stress, mitochondrial dysfunction, environmental, and genetic factors.

The current therapy of Parkinson’s disease is categorized into four classes: levodopa, DA agonists, …


Drug Delivery Strategies For The Treatment Of Advanced Lung Cancer And Various Lung Metastases, Elizabeth Bielski Jan 2018

Drug Delivery Strategies For The Treatment Of Advanced Lung Cancer And Various Lung Metastases, Elizabeth Bielski

Wayne State University Dissertations

Lung cancer remains the leading cause of cancer-related deaths in the United States. Secondary lung tumors metastasized from other cancer sites also remains highly prevalent, in which most metastatic tumors cannot be cured with existing therapies. Chemoresistance (multi drug resistance – MDR) that develops intrinsically or acquired is one of the key factors leading to fatality in these patients. MDR develops form a variety of resistance mechanisms that can occur consecutively or concurrently, therefore, making most current treatments unsuccessful. Current therapies have known to slow tumor growth, but rarely provide a cure. Immunotherapy has seen some promise, including the use …


Identification Of Streptococcus Pyogenes Using Raman Spectroscopy, Ehsan Majidi Jan 2018

Identification Of Streptococcus Pyogenes Using Raman Spectroscopy, Ehsan Majidi

Wayne State University Dissertations

Despite the attention that Raman Spectroscopy has gained recently in the area of pathogen identification, the spectra analyses techniques are not well developed. In most scenarios, they rely on expert intervention to detect and assign the peaks of the spectra to specific molecular vibration. Although some investigators have used machine-learning techniques to classify pathogens, these studies are usually limited to a specific application, and the generalization of these techniques is not clear. Also, a wide range of algorithms have been developed for classification problems, however, there is less insight to applying such methods on Raman spectra. Furthermore, analyzing the Raman …


Study Of Periodical Flow Heat Transfer In An Internal Combustion Engine, Xi Luo Jan 2017

Study Of Periodical Flow Heat Transfer In An Internal Combustion Engine, Xi Luo

Wayne State University Dissertations

In-cylinder heat transfer is one of the most critical physical behaviors which has a direct influence on engine out emission and thermal efficiency for IC engine. In-cylinder wall temperature has to be precisely controlled to achieve high efficiency and low emission. However, this cannot be done without knowing gas-to-wall heat flux. This study reports on the development of a technique suitable for engine in-cylinder surface temperature measurement, as the traditional method is “hard to reach.” A laser induced phosphorescence technique was used to study in-cylinder wall temperature effects on engine out unburned hydrocarbons during the engine transitional period (warm up). …


Chalcogenide Nanocrystal Assembly: Controlling Heterogeneity And Modulating Heterointerfaces, Jessica Davis Davis Jan 2017

Chalcogenide Nanocrystal Assembly: Controlling Heterogeneity And Modulating Heterointerfaces, Jessica Davis Davis

Wayne State University Dissertations

This dissertation work is focused on developing methods to facilitate charge transport in heterostructured materials that comprise a nanoscale component. Multicomponent semiconductor materials were prepared by (1) spin coating of discrete nanomaterials onto porous silicon (pSi) or (2) self-assembly. Spin-coating of colloidal quantum dot (QD) PbS solutions was employed to create prototype PbS QD based radiation detection devices using porous silicon (pSi) as an n-type support and charge transport material. These devices were initially tested as a photodetector to ascertain the possibility of their use in high energy radiation detection. Short chain thiolate ligands (4-fluorothiophenolate) and anion passivation at the …


Video Stream Adaptation In Computer Vision Systems, Yousef Sharrab Sharrab Jan 2017

Video Stream Adaptation In Computer Vision Systems, Yousef Sharrab Sharrab

Wayne State University Dissertations

Computer Vision (CV) has been deployed recently in a wide range of applications, including surveillance and automotive industries. According to a recent report, the market for CV technologies will grow to $33.3 billion by 2019. Surveillance and automotive industries share over 20% of this market. This dissertation considers the design of real-time CV systems with live video streaming, especially those over wireless and mobile networks. Such systems include video cameras/sensors and monitoring stations. The cameras should adapt their captured videos based on the events and/or available resources and time requirement. The monitoring station receives video streams from all cameras and …


Synthesis Of Discrete Transition Metal (Ni, Fe, Co, Mn) Phosphide Nanoparticles: Compositional Effect On Catalytic And Magnetic Properties, Da Li Jan 2017

Synthesis Of Discrete Transition Metal (Ni, Fe, Co, Mn) Phosphide Nanoparticles: Compositional Effect On Catalytic And Magnetic Properties, Da Li

Wayne State University Dissertations

This dissertation research is focused on the synthesis, characterization of binary and ternary transition metal (Ni, Co, Fe, Mn) phosphide nanomaterials and their catalytic and magnetic properties.

A phase-control strategy enabling the arrested-precipitation synthesis of nanoparticles of Ni5P4 and NiP2 is presented. The composition and purity of the product can be tuned by changing key synthetic levers, including the metal precursor, the oleylamine (OAm) and Trioctylphosphine (TOP) concentrations, temperature, time and the presence or absence of a moderate temperature soak step to facilitate formation of Ni and/or Ni-P amorphous nanoparticle intermediates.

New CoxFe2-xP nanoparticles (0 ≤ x ≤ 2), Co2-xMnxP …


Product Development Resilience Through Set-Based Design, Stephen H. Rapp Jan 2017

Product Development Resilience Through Set-Based Design, Stephen H. Rapp

Wayne State University Dissertations

Often during a system Product Development program external factors or requirements change, forcing system design change. This uncertainty adversely affects program outcome, adding to development time and cost, production cost, and compromise to system performance. We present a development approach that minimizes the impacts, by considering the possibility of changes in the external factors and the implications of mid-course design changes. The approach considers the set of alternative designs and the burdens of a mid-course change from one design to another in determining the relative value of a specific design. The approach considers and plans parallel development of alternative designs …


Novel Approaches For Assessment Of Copper Toxicity: Fast Scan Cyclic Voltammetry And Optical Bioassays, Annette R. Tremonti Jan 2016

Novel Approaches For Assessment Of Copper Toxicity: Fast Scan Cyclic Voltammetry And Optical Bioassays, Annette R. Tremonti

Wayne State University Dissertations

Anthropogenic activities negatively impact fresh water ecosystems through toxic contaminants that are released into the environment. Copper (Cu) is a water contaminant that is fundamentally persistent once introduced into the environment that has the potential for bioaccumulation. Although Cu toxicity has been studied for decades, there is still a continuing problem with new sources and pathways. New approaches are needed to understand distribution and transport of Cu and its potential for complex biological impacts beyond the simple assessment of lethality. Several novel approaches were used in this research project to advance our understanding of Cu toxicity, including fast scan cyclic …


Enhanced Pump Schedule Optimization For Large Water Distribution Networks To Maximize Environmental And Economic Benefits, Seyed Mohsen Sadatiyan Abkenar Jan 2016

Enhanced Pump Schedule Optimization For Large Water Distribution Networks To Maximize Environmental And Economic Benefits, Seyed Mohsen Sadatiyan Abkenar

Wayne State University Dissertations

For more than four decades researchers tried to develop optimization method and tools to reduce electricity consumption of pump stations of water distribution systems. Based on this ongoing research trend, about a decade ago, some commercial pump operation optimization software introduced to the market. Using metaheuristic and evolutionary techniques (e.g. Genetic Algorithm) make some commercial and research tools able to optimize the electricity cost of small water distribution systems (WDS). Still reducing the environmental footprint of these systems and dealing with large and complicated water distribution system is a challenge.

In this study, we aimed to develop a multiobjective optimization …


Europium(Ii)-Containing Complexes For Responsive Magnetic Resonance Imaging, Levi Alexander Ekanger Jan 2016

Europium(Ii)-Containing Complexes For Responsive Magnetic Resonance Imaging, Levi Alexander Ekanger

Wayne State University Dissertations

The research projects described in this dissertation are focused on studying the oxidation of EuII-containing complexes within the context of responsive MRI. Prior to this research, EuII had not been explored within the context of oxidation-responsive MRI nor had the use of this ion been reported in vivo. The results of these studies enable predictions about the oxidation-responsive behavior of EuII-containing complexes in vitro and in vivo.

The EuII-containing cryptate 1.33 was used to evaluate EuII-based positive contrast enhancement after intravenous, intraperitoneal, and subcutaneous injections. The transitory behavior of the positive contrast enhancement correlated with reported levels of oxygenation and …


Dielectric Anomalies Of Both Chiral And Achiral Nematogens Near The Isotropic To Mesogenic Phase Transition, Garrett Justin Godfrey Jan 2016

Dielectric Anomalies Of Both Chiral And Achiral Nematogens Near The Isotropic To Mesogenic Phase Transition, Garrett Justin Godfrey

Wayne State University Dissertations

The dielectric properties of nematic liquid crystals were studied in both the achiral and chiral limits. For achiral nematics, the literature documents that pretransitional curvature occurs for polar molecules on both sides of the nematic and isotropic phase transition. This curvature is due to anti-parallel dimer formation. However, past models have failed to quantitatively describe pretransitional curvature. Through a generalization of the order parameter, a macroscopic model has been developed to mathematically describe the pretransitional curvature on the isotropic side of the transition. The new model was fitted to dielectric data from the literature. Meaningful parameter estimates were extracted.

The …


Nano-Structured Electrocatalysts For High Performance Lithium Sulfur Batteries, Negar Mosavati Jan 2016

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 …