Materials Science and Engineering Commons^™

Dft Study Of NiM@Pt1AuN-M-1 (N=19, 38, 55, 79; M = 1, 6, 13, 19) Core-Shell Orr Catalyst, Wen-Jie Li, Dong-Xu Tian, Hong Du, Xi-Qiang Yan

Journal of Electrochemistry

The slow kinetics of oxygen reduction reaction (ORR) limits the performance of low temperature fuel cells. Thus, it needs to design effective catalysts with low cost. Core-shell clusters (CSNCs) show promising activity because of their size-dependent geometric and electronic effects. The ORR activity trend of Ni_m@Pt₁Au_n-m-1(n = 19, 38, 55, 79; m = 1, 6, 13, 19) was studied using the GGA-PBE-PAW methods. The adsorption configurations of *O, *OH and *OOH were optimized and the reaction free energies of four proton electron (H⁺ + e^-) transfer steps …

Preparation And Electrochemical Evaluation Of Mos2/Graphene Quantum Dots As A Catalyst For Hydrogen Evolution In Microbial Electrolysis Cell, Hong-Yan Dai, Hui-Min Yang, Xian Liu, Xiu-Li Song, Zhen-Hai Liang

Journal of Electrochemistry

Microbial electrolysis cell (MEC) is a relatively new bioelectrochemical technology that produces H₂ and meanwhile treats organic wastewater. Cathode hydrogen evolution catalyst plays a key role in MEC. The doping of Graphene Quantum Dots (GQDs) into MoS₂ nanosheets can improve the catalytic activity of MoS₂ by creating abundant defect sites both in the edge plane and the basal plane, as well as enhancing the electrical conductivity. In this paper, using Na₂MoO₄ , cysteine and GQDs as raw materials, a series of MoS₂/GQDs composites were firstly synthesized via hydrothermal method, and then loaded …

Study On Inhibition Of Lithium Dendrite Growth By Mg(No3)2 Additive In Carbonate Electrolyte, Biao Zhang, Yi Shuai, Yu Wang, Na-Chuan Yang, Kang-Hua Chen

Journal of Electrochemistry

In the lithium-sulfurized polyacrylonitrile battery system, the formation and growth of lithium dendrites in the negative electrode seriously deteriorate the charge and discharge performance of the battery. If the growth of lithium dendrites pierces the separator and causes thermal runaway, it will also bring serious damage to the battery, causing potential safety risks. In the carbonate electrolyte that is more conducive to stabilizing the positive electrode sulfurized polyacrylonitrile material, the growth of lithium dendrites is particularly serious. In this paper, magnesium nitrate was added to the carbonate electrolyte to investigate the combined effect of nitrate and magnesium ions on the …

A Preliminary Study On Graphene Film-Metal Composites Prepared By Electrodeposition, Shuang-Juan Liu, Hai-Jing Wang, Jing Guo, Peng-Cheng Wang, Hao Zhou, Cai Meng, Han-Jie Guo

Journal of Electrochemistry

Graphene film (GF) has excellent electrical and thermal conductivity, but low strength and hardness. In order to obtain good comprehensive mechanical properties to improve the practical value of GF, the concept of preparing GF-metal composite materials was proposed. This work was conducted to preliminarily study the feasibility of using electrodeposition method to prepare GF-metal composites. Two kinds of composites, GF-Cu and GF-Cr, were successfully prepared by using GF as the cathode, and pure Cu and DSA (Dimensionally Stable Anode) as the anodes, respectively, with applying DC power externally. Employing certain electrochemical parameters, the cation in the electrolyte moved towards the …

Effect Of Conductive Additives On Electrochemical Performance Of All-Solid-State Li-S Batteries, Dong-Hao Wang, He-Feng Yan, Zheng-Liang Gong

Journal of Electrochemistry

All-solid-state lithium sulfur batteries (ASSLSBs) with inorganic solid electrolytes offer an opportunity to realize both high energy density (lithium metal ~ 3860 mAh·g^-1, sulfur ~ 1675 mAh·g^-1), safety and reliability, via eliminating the polysulfides shuttle effect and flammable liquid electrolyte. However, it still remains a huge challenge for ASSLSBs to achieve high areal active mass loading, high utilization efficiency of the active materials and good cycle stability simultaneously due to the insulating nature of sulfur and Li₂S (conductivities of sulfur and Li₂S are 5×10^-30 S·cm^-1 and 3.6×10^-7 S·cm^{-1 …}

Preparation Of Coo/Rgo@Ni Foam Electrode And Its Electrocatalytic Reduction Of Co2, Qian Guo, Jia-Long Fu, Cheng-Yan Zhang, Chao-Yue Cai, Cheng Wang, Li-Hua Zhou, Rui-Bo Xu, Ming-Yan Wang

Journal of Electrochemistry

The worldwide extensive release of carbon dioxide (CO₂) has caused serious environmental pollution and unprecedented climate change problems. Thus, for the sustainable development of human society, it is very necessary to convert CO₂ to renewable fuels through clean and economical processes. The electrochemical CO₂ reduction reaction (CO₂RR) is regarded as a promising approach for the recycling of carbon resource and the generation of sustainable fuels. However, the slow kinetics and formation of multiple products in CO₂RR hinder its large-scale application. Hence, great research efforts are made to develop electrocatalysts with high product …

High Depth-Of-Discharge Zinc Rechargeability Enabled By A Self-Assembled Polymeric Coating, David J. Arnot, Matthew B. Lim, Nelson S. Bell, Noah B. Schorr, Ryan C. Hill, Andrew Meyer, Yang-Tse Cheng, Timothy N. Lambert

Chemical and Materials Engineering Faculty Publications

Zinc has the potential for widespread use as an environmentally friendly and cost-effective anode material pending the resolution of rechargeability issues caused by active material loss and shape change. Here, a self-assembled Nafion-coated Celgard 3501 (NC-Celgard) separator is shown to enable unprecedented cycle life of a Zn anode in alkaline electrolyte at high depth-of-discharge (DOD_Zn). Using commercially relevant energy-dense electrodes with high areal capacities of 60 mAh cm^–2, Zn–Ni cells tested at 20% DOD_Zn cells achieve over 200 cycles while 50% DOD_Zn cells achieve over 100 cycles before failure. The 20% and 50% DOD …

Engineering The Surface Of Fe3o4 Nanoparticles For Catalytic And Magnetic Applications, Natalia Da Silva Moura

LSU Doctoral Dissertations

With the rapid depletion of the U.S. energy resources coupled with population growth, heat management technologies must be improved to sustain our quality of life. Precisely, in catalysis, it is estimated that only ~50% of the energy supplied to the reactor is used for product conversion due to dissipation losses. Among the emerging technologies with a promising reduction in heat losses is induction heating, offering targeted heat delivery with magnetic nanoparticles. Under alternating magnetic fields (AMF), these nanoparticles can absorb the energy from Radio-Frequency (RF) fields and dissipate it as heat on the nanoparticle surface. This in situ heat generation …

Evaluation Of Stretch Film Behavior During Long-Term Storage Under Different Atmospheric Conditions, Kyle Dunno, Maria Symanski

Journal of Applied Packaging Research

This study examined the post-application behavior of two 20.3 micron machine stretch films, one categorized as high-performance and one as general-performance, for thirty days while stored at either 23°C or 38°C. For each film type, the stretch film was applied to a simulated unit load to produce neutral and positive applied total stretch scenarios. The relaxation curves developed from each test indicate the relaxation rate of the films varied based on the storage condition. Observed was an average of 41% containment loss for both high-performance and general-purpose films when the simulated loads were stored at 38°C. For simulated loads stored …

A Xanes Study Of Lithium Polysulfide Solids: A First-Principles Study, Qing Guo, Kah Chun Lau, Ravindra Pandey

Michigan Tech Publications, Part 1

X-ray absorption spectroscopy (XAS) is used for capturing the reaction mechanisms at the molecular level via the determination of local electronic configurations inside Li-S batteries. In this paper, a comprehensive investigation of the S K-edge X-ray absorption near-edge structure (XANES) of a series of stoichiometric lithium polysulfide solids was performed, assuming that these polysulfide solids are formed during the battery cycling process. The results based on density functional theory show that the pre-edge peak in the S K-edge XANES spectra is not a common feature in the solid phase in contrast to the case of pristine polysulfide molecules where the …

Analytical Model For Electromagnetic Induction In Pulsating Ferrofluid Pipe Flows, Huiyu Wang, John G. Monroe, Swati Kumari, Serhiy O. Leontsev, Erick S. Vasquez, Scott M. Thompson, Matthew J. Berg, Dibbon Keith Walters, Keisha B. Walters

Chemical and Materials Engineering Faculty Publications

No abstract provided.

Laser Surface Treatment And Laser Powder Bed Fusion Additive Manufacturing Study Using Custom Designed 3d Printer And The Application Of Machine Learning In Materials Science, Hao Wen

LSU Doctoral Dissertations

Selective Laser Melting (SLM) is a laser powder bed fusion (L-PBF) based additive manufacturing (AM) method, which uses a laser beam to melt the selected areas of the metal powder bed. A customized SLM 3D printer that can handle a small quantity of metal powders was built in the lab to achieve versatile research purposes. The hardware design, electrical diagrams, and software functions are introduced in Chapter 2. Several laser surface engineering and SLM experiments were conducted using this customized machine which showed the functionality of the machine and some prospective fields that this machine can be utilized. Chapter 3 …

Silk Fibroin Supraparticles Created By The Evaporation Of Colloidal Ouzo Droplets, Ashley Lamb, Fengjie He, Shengjie Zhai, Hui Zhao

Mechanical Engineering Faculty Research

Due to its high biocompatibility and biodegradability, supraparticles made from silk fibroin—produced from Bombyx mori (B. mori) cocoons—can find various applications in biomedical fields. The evaporation of Ouzo droplets by not requiring energy nor a surfactant is an environmentally friendly, easy, and cost-effective strategy to fabricate three-dimensional supraparticles, tackling the so-called “coffee ring effect” associated with droplet evaporation. Silk fibroins are dissolved into quaternary droplets, comprised of ultrapure water, ethanol, trans-anethole oil, and formic acid. The Ouzo droplet is able to form an oil ring that facilitates the droplet contraction to create a three-dimensional supraparticle. Using the Ouzo effect to …

Metal Oxide Nanoparticles Synthesized By Nonthermal Plasma For Electrochemical Applications, Qinyi Chen

McKelvey School of Engineering Graduate Student Theses & Dissertations

Metal oxide nanocrystals can be synthesized by colloidal processing and gas-phase processing routes. High-quality nanocrystals produced by colloidal routes typically have surface ligands. Transport of electrons and ions among nanocrystals is hindered by surface ligand, and degrades related electrical performance. Gas-phase processing, for example combustion and thermal plasma, can make free-standing nanocrystals. However, nanocrystals produced by combustion method are heavily agglomerated, which further limits the usage of nanoparticles in electrochemical applications. Nonthermal plasma, as an emerging attractive route, has been initially focused on the synthesis of elemental group IV materials, and extended to include the synthesis of multicomponent materials, such …

Novel Photothermal Materials And Thermally Engineered Membranes For Solar Desalination, Sisi Cao

McKelvey School of Engineering Graduate Student Theses & Dissertations

Although 71% of earth surface is covered with water, more than 97% of it is saltwater, and freshwater is limited to only about 2.5%. The freshwater shortage has been exacerbated due to the environmental pollution, increased agriculture needs, socio-economic development, and population growth. Among various desalination technologies, membrane distillation has gained wide attention due to its ability to treat highly saline water utilizing waste heat from industrial processes. However, the implementation of conventional membrane distillation is hindered in the remote regions and disaster-struck communities where the low-grade thermal energy from industrial plants and electricity are not readily available. To address …

Flexible Electronics For Neurological Electronic Skin With Multiple Sensing Modalities, Haochuan Wan

McKelvey School of Engineering Graduate Student Theses & Dissertations

The evolution of electronic skin (E-skin) technology in the past decade has resulted in a great variety of flexible electronic devices that mimic the physical and chemical sensing properties of skin for applications in advanced robotics, prosthetics, and health monitoring technologies. The further advancement of E-skin technology demands closer imitation of skin receptors' transduction mechanisms, simultaneous detection of multiple information from different sources, and the study of transmission, processing and memory of the signals among the neurons. Motivated by such demands, this thesis focuses on design, fabrication, characterization of novel flexible electronic devices and integration of individual devices to realize …

Nucleation Studies In Barium Silicate Glasses And Soda-Lime Silicate Glass, Xinsheng Xia

McKelvey School of Engineering Graduate Student Theses & Dissertations

Controlling nucleation is key for the manufacture of glasses and glass-ceramics. It has been observed by different researchers in many silicate glasses that at low temperatures the critical work of cluster formation (i.e. the nucleation barrier) slowly rises rather than decreasing with decreasing temperature. However, this experimental observation is in contradiction with nucleation theories. In this dissertation, crystal nucleation was studied in BaO·2SiO2, 5BaO·8SiO2, and Na2O·2CaO·3SiO2 glasses. The main research topics include measurements of the nucleation rate, the structural evolution of the glass, and the low-temperature nucleation behavior. A special focus is given to the low-temperature nucleation anomaly. In total, …

Direct Activation Of Light Alkanes To Value-Added Chemicals Using Supported Metal Oxide Catalysts, Md Ashraful Abedin

LSU Doctoral Dissertations

One of the most challenging aspects of modern-day catalysis is the conversion of methane. Direct conversion of methane via dehydroaromatization (MDHA) is a well-known process which can produce valuable hydrocarbons. Mo oxide supported on ZSM-5/MCM-22 has been studied extensively in recent years for MDHA. Mo carbides are responsible for activating methane by forming CHx species. These are dimerized into C2Hy and oligomerized on ZSM-5/MCM-22 Brønsted acid sites to form aromatics. Sulfated zirconia (SZ) supported Mo catalyst contains the acid sites necessary to produce benzene in MDHA. Here, sulfated hafnia (SH), a homologous oxide like SZ, has been proposed to provide …

Martensitic And Inter-Martensitic Transformations In Magnetocaloric Ni2.15mn0.85ga Heusler Alloy, A. Madiligama, P. Ari-Gur, Y, Ren, V, Shavrov, Y. Ge, J. George, I. Musabirov, V. Koledov

Mechanical and Aerospace Engineering Faculty Publications

The entropy changes of successive martensitic phase transformations in Ni-Mn-Ga Heusler alloys can be utilized to realize enhanced magnetocaloric properties. A detailed study of phase transformations of one such alloy, Ni2.15Mn0.85Ga, (ΔQ = 4900 J/kg at 343 K, under 140 kOe), is reported here. Upon cooling, the paramagnetic cubic (L21) austenitic phase transforms into a ferromagnetic 7M modulated monoclinic martensitic phase. This phase is stable in a narrow temperature range, and upon further cooling, transforms into a non-modulated ferromagnetic tetragonal (L10) phase. The separation between the equilibrium temperatures of the austenitic and tetragonal martensitic phases is only ~50 K. The …

Findings Report: Virtual Workshop On ‘Resilient Supply Of Critical Minerals’, Marek Locmelis, Angela D. Lueking, Michael S. Moats, Kwame Awuah-Offei, Lana Z. Alagha, Mark W. Fitch, Alanna Krolikowski, Shelby Clark

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Executive Summary
On August 2-3, 2021, the Thomas J. O’Keefe Institute for Sustainable Supply of Strategic Minerals at Missouri University of Science and Technology (Missouri S&T) hosted the NSF-funded virtual workshop ‘Resilient Supply of Critical Minerals’. The workshop was convened via Zoom and attracted 158 registrants, including 108 registrants from academia (61 students), 30 registrants from government agencies, and 20 registrants from the private sector. Four topical sessions were covered:

A. Mineral Exploration and Source Diversification.
B. Supply Chain and Policy Issues.
C. Improving Mineral Recycling and Reprocessing Technologies.
D. Technological Alternatives to Critical Minerals.

Each topical session was composed …