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Full-Text Articles in Physical Sciences and Mathematics

Applying Density Functional Theory Simulations To Study The Charge Balancing And Structure Directing Roles Of Fluoride In Zeolite Synthesis, Tongkun Wang Nov 2023

Applying Density Functional Theory Simulations To Study The Charge Balancing And Structure Directing Roles Of Fluoride In Zeolite Synthesis, Tongkun Wang

Doctoral Dissertations

Zeolites represent a major cornerstone of today’s energy industry as the most-used petrochemical catalyst by weight in the world. Constituted by tetrahedra of T-atoms including Si, Al, Ge and Ti, zeolites form a huge family of nano-porous crystalline materials which also provide reliable candidates for novel, energy related applications such as efficient separations, hydrogen-purifying/storing and conversions from biomass to biofuel. However, the formation mechanism of zeolite is still not clear, as synthesis processes are complicated by requirements including structure directing agents (SDAs), hydroxide or fluoride medium, and experimental conditions like temperature. Attempts for designing new zeolite structures still fall in …


Photophysical And Photochemical Processes In Small Molecules And Materials For Solar Energy Conversion, Ethan Lambert May 2023

Photophysical And Photochemical Processes In Small Molecules And Materials For Solar Energy Conversion, Ethan Lambert

Honors Theses

The work covered in this thesis all falls under the theme of photophysical processes after light and matter interact. Those of primary interest are Raman scattering induced vibrations and excited state dynamics probed by transient absorption spectroscopy. Small molecules are studied with Raman spectroscopy and computational chemistry. These studies unearth the shifts in vibrational frequency as a function of charge transfer or receipt and how a quantitative assay of natural orbital populations and delocalization can offer both the nature and magnitude of this charge transfer. Further, a method is presented that builds upon previous work within the academic family tree; …


Detection Of Nitrogen Dioxide Via Graphene-Enhanced Raman Scattering, Spencer Hazeslip May 2023

Detection Of Nitrogen Dioxide Via Graphene-Enhanced Raman Scattering, Spencer Hazeslip

Chemistry & Biochemistry Undergraduate Honors Theses

This paper presents the development of a nitrogen dioxide (NO2) sensor that utilizes the phenomenon of graphene-enhanced Raman scattering (GERS). The sensor consists of monolayer graphene on a silicon wafer, functionalized noncovalently with Copper(II) 2,9,16,23-tetra-tert-butyl-29H,31H-phthalocyanine (CuTTPc) via the solution soaking method. A custom sensing chamber was constructed to enable Raman spectra to be collected during NO2 exposure. The response of the sensor was found to be linear between 10 and 100 ppm NO2, indicating that it could be used for both detection and quantification. Furthermore, the sensor was shown to be reusable after …


Analysis Of Forensically Relevant Evidence Using Electrochemistry, Spectroscopy, And Mass Spectrometry Tools, Colby Edward Ott Jan 2022

Analysis Of Forensically Relevant Evidence Using Electrochemistry, Spectroscopy, And Mass Spectrometry Tools, Colby Edward Ott

Graduate Theses, Dissertations, and Problem Reports

Forensic science relies on the use of multiple techniques in the assessment of evidence to increase the accuracy and reliability of the results. However, with the rapidly changing drug landscape due to the introduction of novel psychoactive substances, many traditional screening methods are no longer sensitive or selective enough for use. Additionally, many screening methods such as chemical color tests are prone to false positive and negative results and are subjective. Therefore, the goal of this dissertation was to develop a novel analytical scheme that can provide a more efficient, rapid, and sensitive method that will facilitate adoption in the …


Structural Tuning And Spectroscopic Characterizations Of Polysulfide As Battery Materials, Daiqiang Liu Oct 2021

Structural Tuning And Spectroscopic Characterizations Of Polysulfide As Battery Materials, Daiqiang Liu

Electronic Thesis and Dissertation Repository

Polysulfide materials have drawn extensive attention for next-generation battery development since the current lithium-ion battery has almost reached its limit regarding energy density and safety issues. Many phosphorus and sodium sulfide materials have been used in different battery types, such as solid-state and sodium-sulfur batteries. However, there are still issues that prevent these techniques from applications. In recent years, there has been increasing attention on investigations of the structural and phase transformations of electrode and electrolyte materials under high pressure. Many studies have shown that external pressure can affect structural properties and influence electrical properties. In this study, three battery-related …


Synthesis And Raman Study Of Hollow Core-Shell Ni1.2Co0.8P@N-C As An Anode Material For Sodium-Ion Batteries, Jia-Hui Chen, Xiao-Bin Zhong, Chao He, Xiao-Xiao Wang, Qing-Chi Xu, Jian-Feng Li Jun 2020

Synthesis And Raman Study Of Hollow Core-Shell Ni1.2Co0.8P@N-C As An Anode Material For Sodium-Ion Batteries, Jia-Hui Chen, Xiao-Bin Zhong, Chao He, Xiao-Xiao Wang, Qing-Chi Xu, Jian-Feng Li

Journal of Electrochemistry

With the increasing demand for large-scale energy storage, great progress has been made in discovering new advanced energy storage materials. Sodium-ion batteries (SIBs) have attracted much attention in recent years due to their use of abundant sodium resources and their comparable electrochemical capacity to lithium-ion batteries (LIBs). In this paper, we developed novel hollow core-shell Ni-Co bimetallic phosphide nanocubes with N-doped carbon coatings (Ni1.2Co0.8P@N-C) as the anode material for SIBs. The material was synthesized through a low-temperature phosphorization method using resorcinol formaldehyde (RF) resin coating with a Ni-Co Prussian blue analogue (PBA) as a template and …


An In-Situ Study Of The Aqueous Speciation Of Uranium (Vi) Under Hydrothermal Conditions, Diwash Dhakal May 2019

An In-Situ Study Of The Aqueous Speciation Of Uranium (Vi) Under Hydrothermal Conditions, Diwash Dhakal

MSU Graduate Theses

Rigorous study of the speciation distribution of uranyl-chloride bearing solutions under hydrothermal conditions is important to understand the transport mechanism of uranium underground, which is of uttermost interest to parties studying the geological uranium deposits and those studying the possibilities of geological repositories for spent nuclear waste. I report an in-situ Raman spectroscopic study of the speciation distribution of aqueous uranyl-chloride complexes upto 500°C conducted using a HDAC as the high PT spectroscopic cell. The samples studied contained the species UO22+, UO2Cl+, UO2Cl20 and UO2Cl3- …


The Corrosion Of Carbon Steel Under Deep Geologic Nuclear Waste Disposal Conditions, Shannon L.W. Hill Jun 2016

The Corrosion Of Carbon Steel Under Deep Geologic Nuclear Waste Disposal Conditions, Shannon L.W. Hill

Electronic Thesis and Dissertation Repository

The proposed disposal scenario for high-level nuclear waste (spent fuel) in Canada is emplacement within a sealed, deep geological repository (DGR) located in either granitic rock or sedimentary clay. Disposal is based on a multi-barrier approach, with the primary barrier being a sealed container which could be either dual-walled with a copper shell over an inner carbon steel vessel for granitic rock or a single thick-walled steel container for sedimentary clay. This study focuses on the corrosion behaviour of A516 Gr70 carbon steel as well as the corrosion products formed in a variety of groundwater compositions and concentrations expected within …


In Situ High-Pressure Study Of Metal-Organic Frameworks And Their Performance For Co2 Storage Probed By Vibrational Spectroscopy, Yue Hu Aug 2015

In Situ High-Pressure Study Of Metal-Organic Frameworks And Their Performance For Co2 Storage Probed By Vibrational Spectroscopy, Yue Hu

Electronic Thesis and Dissertation Repository

Metal-organic frameworks (MOFs) are an important class of porous materials, owing to their potential applications in a variety of areas, including gas storage, molecular separations, catalysis, sensors and so on. Most importantly, their extraordinary surface areas, tunable pore properties and potential for industrial scale production have made MOFs a promising material for clean energy applications, such as CO2 storage. The chemical and mechanical stabilities of MOFs play a crucial role in their CO2 storage performance, which require extreme loading pressures that are far beyond ambient pressure at times. Application of high external pressure (e.g., in gigapascal range) on …


Applications Of Raman Spectroscopy Technique In Lithium Ion Batteries, Liang Zhao, Yong-Sheng Hu, Hong Li, Zhao-Xiang Wang, Hong-Xing Xu, Xue-Jie Huang, Li-Quan Chen Feb 2011

Applications Of Raman Spectroscopy Technique In Lithium Ion Batteries, Liang Zhao, Yong-Sheng Hu, Hong Li, Zhao-Xiang Wang, Hong-Xing Xu, Xue-Jie Huang, Li-Quan Chen

Journal of Electrochemistry

The Raman spectroscopy has been widely used in the study of lithium ion batteries.In this short review,we gave some examples of the applications of Raman spectroscopy in the study of electrode materials including carbonaceous materials,spinel LiMxMn2-x O4,LiFePO4,as well as polymer electrolytes,room temperaturemolten salt electrolytes and the solid-electrolyte interphase layers.The advantages and disadvantages of the ex-situ and in-situ Raman spectrum techniques are discussed.Using new Raman techniques to investigate Li-ion batteries are suggested.


Electrochemical Surface-Enhanced Raman Spectroscopy—Current Status And Perspective, Bin Ren, Jian-Feng Li, Yi-Fan Huang, Zhi-Cong Zeng, Zhong-Qun Tian Aug 2010

Electrochemical Surface-Enhanced Raman Spectroscopy—Current Status And Perspective, Bin Ren, Jian-Feng Li, Yi-Fan Huang, Zhi-Cong Zeng, Zhong-Qun Tian

Journal of Electrochemistry

Electrochemical interface is a very important interface closely related to various energy and life processes. Surface-enhanced Raman scattering was widely used in electrochemistry soon after its discovery to understand the surface bonding,configuration,and orientation of the surface species. In recent 10 years,the fast development of nanoscience and nanotechnology has offered SERS with abundant substrates and characterization methods,which has allowed impressive development of electrochemical SERS. This articles will follow the time line to make systematically overview of SERS on Au and Ag,thin-layer transition-metal SERS,pure transition metal SERS,core-shell SERS and those methods for studying single crystal surfaces,including gap-mode SERS, TERS and SHINERS. Emphasis …


In Situ Surface-Enhanced Raman Scattering Spectroscopic Study Of Sulfur Adsorption On Polycrystalline Platinum Electrode Surface, Bolian Xu-, In-Su Park, Ying Li, De-Jun Chen, Yuye J. Tong Aug 2010

In Situ Surface-Enhanced Raman Scattering Spectroscopic Study Of Sulfur Adsorption On Polycrystalline Platinum Electrode Surface, Bolian Xu-, In-Su Park, Ying Li, De-Jun Chen, Yuye J. Tong

Journal of Electrochemistry

The paper reports the first in situ surface enhanced Raman scattering (SERS) spectroelectrochemistry study of sulfur adsorption and electro-oxidation on highly roughened polycrystalline Pt surface in both acidic and basic supporting electrolytes. The SERS spectra were taken at a constant electrode potential after accumulative electro-oxidation CVs of the Pt electrode with pre-adsorbed sulfur species and at different electrode potentials that were varied stepwise of the Pt electrode immersed in sulfur-containing electrolytes without pre-adsorbed sulfur species. In both cases,a dominant vibrational band at 299 cm -1 in acidic electrolyte but at 310 cm-1 in basic electrolyte was observed,which was assigned to …


A Sutface-Enhanced Raman Spectroscopic Study On The Inhibition Mechanism Of Bmat On Stainless Steel In Hydrochloric Acid Solutions, Yinghua Zha, Baoming Wei May 1995

A Sutface-Enhanced Raman Spectroscopic Study On The Inhibition Mechanism Of Bmat On Stainless Steel In Hydrochloric Acid Solutions, Yinghua Zha, Baoming Wei

Journal of Electrochemistry

The absorbtion of some nitrogen and sulfur compounds such as BMAT on 18-8stainless steel(SS)in 0.5% HCl were investigated by surface enhanced Raman scattering(SERS)spectroscopy.The SERS spectra of BMAT adsorbed on SS were measured using a SS electredepositedwith discontin uous silvet micro-islands.The results show that the inhibitor,BMAT,is chemisorbed onthe SS surface through the N atom. Under the influence of π-electron interaction ,BMAT can beadsorbed on SS surface at an angle. The allyls in BMAT molecules play the role of steric hindrance inthe inbibition effect.