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Full-Text Articles in Materials Chemistry

Carbon Dioxide-Induced Corrosion Of Aisi 4140 Steel In Acidified Artificial Geothermal Brine, Anawati Anawati, Rayhan Izzat, Riene Kaelamanda Pragitta, Rafli Ihsan Hernandi Mar 2023

Carbon Dioxide-Induced Corrosion Of Aisi 4140 Steel In Acidified Artificial Geothermal Brine, Anawati Anawati, Rayhan Izzat, Riene Kaelamanda Pragitta, Rafli Ihsan Hernandi

Makara Journal of Science

Carbon dioxide (CO2)-induced corrosion often occurs in the structural materials of geothermal industry. The presence of CO2 influences the formation of various corrosion products. This research investigates the effect of dissolved CO2 in acidic brines on the corrosion behavior of AISI 4140 steel at atmospheric pressure. The brines were the standard brine, Ca-free brine, and high-salinity brine. The corrosion behavior was studied using electrochemical and immersion tests. A cyclic polarization test showed that the corrosion rate was higher in dissolved CO2 brine than in non-CO2 brine, and an immersion test demonstrated a similar result. …


Investigating The Structure Of Metal-Organic Frameworks And The Behaviors Of Adsorbed Guest Molecules In Mofs Via Solid-State Nmr Spectroscopy, Yihao Shen Feb 2023

Investigating The Structure Of Metal-Organic Frameworks And The Behaviors Of Adsorbed Guest Molecules In Mofs Via Solid-State Nmr Spectroscopy, Yihao Shen

Electronic Thesis and Dissertation Repository

Metal-organic frameworks (MOFs) are a class of hybrid organic-inorganic microporous materials with lots of significant applications including gas capture and storage, gas separation, batteries, catalysis, ion exchange and drug delivery. MOFs based on s-block metals are important due to their many practical applications. These MOFs are also very interesting because the s-block MOFs often exhibit unpredictable behavior of coordination. In this thesis, the structures of six s-block metal (Li, Na, Cs, Mg, Ca, Sr) based MOFs involving V-shaped link, 4, 4′- sulfonyldibenzoate (SDB) are characterized by various techniques including, powder X-ray diffraction, TGA and solid-state NMR spectroscopy. 13C CPMAS …


Carbon Dioxide Capture Potential Of Chitosan-Nanocrystalline Cellulose Aerogel Composite Materials: Synthesis, Functionalization, And Characterization, Victor Oghenekohwo Jan 2023

Carbon Dioxide Capture Potential Of Chitosan-Nanocrystalline Cellulose Aerogel Composite Materials: Synthesis, Functionalization, And Characterization, Victor Oghenekohwo

Theses and Dissertations

The carbon dioxide capture technology has been established as an invaluable player in the current global efforts to allay the warming of the planet and climate change. In this connection, the study centers on the valorization of waste organic materials for the application described herein. The sorbents, sourced from a combination of by-products of food processing and agricultural residue waste products, viz. seafood waste and sugarcane bagasse, showed prospects for selective carbon dioxide capture, adsorbing up to 5.78 mg/g of the gas at 273 K and 2.82 mg/g at 298 K, as observed on the Micromeritic ASAP 2020 surface area …


Pressure - Temperature Phase Diagram Of Crsite3, J L. Musfeldt, David Mandrus, Zhenxian Liu Jan 2023

Pressure - Temperature Phase Diagram Of Crsite3, J L. Musfeldt, David Mandrus, Zhenxian Liu

Chemistry Publications and Other Works

van der Waals solids are well known to host remarkable phase diagrams with competing phases, unusual energy transfer processes, and elusive states of matter. Among this class of materials, chalcogenides have emerged as the most flexible and relevant platforms for unraveling charge-structure-function relationships. In order to explore the properties of complex chalcogenides under external stimuli, we measured the far infrared spectroscopic response of CrSiTe3 under extreme pressure-temperature conditions. Analysis of the 368 cm−1 Si-Te stretching mode and the manner in which it is screened by the closure of the indirect gap reveals that the insulator-metal transition takes place immediately after …


Potential Of Biduri Fiber (Calotropis Gigantea) As Material For Oil Spill Absorbent, Anne Sukmawati, Wulan Septiani Jan 2023

Potential Of Biduri Fiber (Calotropis Gigantea) As Material For Oil Spill Absorbent, Anne Sukmawati, Wulan Septiani

Journal of Materials Exploration and Findings (JMEF)

Biduri fiber (Calotropis gigantea) is a natural hollow fiber with hydrophobic and oleophilic properties potentially used as oil spilled sorbent from seawater. This study aims to determine the absorption capacity and efficiency of the Biduri fiber and membrane to fuel oil. Measurement of oil absorption to seawater was carried out at various fiber weights (0.5-1.5 g), fiber composition (50-95%), contact time (10-90 minutes), temperature (30 and 50°C), and compared with commercial products. The results showed that the fiber weight variation of 0.5-1.5 g has an average absorption efficiency of 96.67%, and the highest absorption was obtained in a weight of …


Development Of Battery Materials To Function As Corrosion Protection On Car Body Plates, Tubagus Noor Rohmannudin, Sulistijono Sulistijono, Noval Adrinanda, Faridz Wira Dharma, Samuel Areliano Jan 2023

Development Of Battery Materials To Function As Corrosion Protection On Car Body Plates, Tubagus Noor Rohmannudin, Sulistijono Sulistijono, Noval Adrinanda, Faridz Wira Dharma, Samuel Areliano

Journal of Materials Exploration and Findings (JMEF)

Most car bodies made for mass production are made from steel or aluminum. Both are strong metals, but steel is cheaper than aluminum and is more commonly used in lower-end cars for a broader consumer range. The weakness of steel compared to aluminum is that it is susceptible to corrosion under certain conditions, and thus it may deteriorate over time without proper care. To prevent corrosion, modern cars are coated with paint to prevent direct contact with the environment. As a second line of protection, a car battery can be connected to the body to create an impressed current cathodic …


Influence Of Synthesis Conditions On The Physicochemical And Electrocatalytic Properties Of Non-Stoichiometric Ba2sr2la2ti4o12 Perovskites, Ofeliya Kostadinova, Iliyan Popov, Simeon M. Stankov, Hristo Kolev, Tamara Petkov Jan 2023

Influence Of Synthesis Conditions On The Physicochemical And Electrocatalytic Properties Of Non-Stoichiometric Ba2sr2la2ti4o12 Perovskites, Ofeliya Kostadinova, Iliyan Popov, Simeon M. Stankov, Hristo Kolev, Tamara Petkov

Karbala International Journal of Modern Science

Present work studies the influence of the pretreatment milling media (deionized water (BLTOS-H) and isopropanol (BLTOS-i)) on the surface characteristics, structure, chemical composition and catalytic activity of non-stoichiometric Ba2Sr2La2Ti4O12 perovskites. The IR spectroscopy and XRD analyses shows a difference in the structure and phase composition of the two materials. X-ray photoelectron spectroscopy detects a Ba2+- and La3+-enriched and Sr2+-depleted surface. The BLTOS-i sample appears to exhibit higher specific surface area (SSA) and pore volume in comparison to BLTOS-H. The electrochemical tests showed that BLTOS-H sample have similar behavior to platinum at current densi-ties up to 10 mA cm-2, while BLTOS-i …


Dual Ionic Liquid-Functionalized Cellulosic Materials: Thermal, Mechanical And Conductive Properties, Elizabeth Mcgrew, Kevin M. Miller Phd Jan 2023

Dual Ionic Liquid-Functionalized Cellulosic Materials: Thermal, Mechanical And Conductive Properties, Elizabeth Mcgrew, Kevin M. Miller Phd

Posters-at-the-Capitol

Cellulose, an inexpensive and renewable biomacromolecule, represents an intriguing synthetic foundation for new materials with task-specific properties. Here, we wish to report a synthetic route for functionalizing cellulose with a side chain containing two ionic liquid functional groups using azide-alkyne ‘click’ cyclization strategy, followed by quaternization of the two resulting heterocycles (1,2,3-triazole and imidazole). Through this functionalization strategy, the resulting cellulosic materials exhibited significant softening, with several glass transition (Tg) values observed below room temperature, indicating the amorphous nature of the materials, with the Tg dependent on both the length of the side chain and the …


Translating Chemistry, Structure, And Processing To The Solid-State Morphology And Function Of Organic Semiconductors Through Computational Modeling And Simulations, Chamikara D. Karunasena Jan 2023

Translating Chemistry, Structure, And Processing To The Solid-State Morphology And Function Of Organic Semiconductors Through Computational Modeling And Simulations, Chamikara D. Karunasena

Theses and Dissertations--Chemistry

The immense synthetic design space and material versatility have driven the exploration and development of organic semiconductors (OSC) over several decades. While many OSC designs focus on the chemistries of the molecular or polymer building blocks, a priori, multiscale control over the solid-state morphology is required for effective application of the active layer in a given technology. However, molecular assembly during solid-state formation is a complex function interconnecting the building block chemistry and the processing environment. Insufficient knowledge as to how these aspects engage, especially at the atomistic and molecular scales, has so far limited the ability to predict …


Outstanding Advantages, Current Drawbacks, And Significant Recent Developments In Mechanochemistry: A Perspective View, Silvina Pagola Jan 2023

Outstanding Advantages, Current Drawbacks, And Significant Recent Developments In Mechanochemistry: A Perspective View, Silvina Pagola

Chemistry & Biochemistry Faculty Publications

Although known since antiquity, mechanochemistry has remained dormant for centuries. Nowadays, mechanochemistry is a flourishing research field at the simultaneous stages of gathering data and (often astonishing) observations, and scientific argumentation toward their analysis, for which the combination of interdisciplinary expertise is necessary. Mechanochemistry’s implementation as a synthetic method is constantly increasing, although it remains far from being fully exploited, or understood on the basis of fundamental principles. This review starts by describing many remarkable advantages of mechanochemical reactions, simplifying and “greening” chemistry in solutions. This description is followed by an overview of the current main weaknesses to be addressed …


Feasibility Studies For Use Of Copper Slag In Clinker Manufacture, Suresh Vanguri, Suresh Palla, Gonthi Prasad, Sanjeev Kumar Chaturvedi, Bibekananda Mohapatra Dec 2022

Feasibility Studies For Use Of Copper Slag In Clinker Manufacture, Suresh Vanguri, Suresh Palla, Gonthi Prasad, Sanjeev Kumar Chaturvedi, Bibekananda Mohapatra

Makara Journal of Science

This study investigated the feasibility of using copper slag (CS-C) as a raw material in the production of Portland cement (PC). The effect of addition of 0%-3.5% CS-C on the clinkerization process, mineralogy, microstructure, and compressive strength development was studied. The Presence of CS-C in the raw mix resulted in the reduced temperature of clinkerization by about 50 °C. The quality of clinker prepared from the raw mix containing 3% CS-C and burned at 1400 °C was comparable to that of clinker prepared from the raw mix containing no CS-C and burned at 1450 °C. Gradual polymorphic modification of alite …


Advances On Composite Cathodes For Lithium-Sulfur Batteries, Xi-Yao Li, Chang-Xin Zhao, Bo-Quan Li, Jia-Qi Huang, Qiang Zhang Dec 2022

Advances On Composite Cathodes For Lithium-Sulfur Batteries, Xi-Yao Li, Chang-Xin Zhao, Bo-Quan Li, Jia-Qi Huang, Qiang Zhang

Journal of Electrochemistry

Lithium-sulfur (Li-S) batteries are deemed as high-promising next-generation energy storage technique due to their ultrahigh theoretical energy density, where the sulfur cathodes with high specific capacity guarantee the energy density advantage and directly determine the battery performances. After decades of exploration, the most promising sulfur cathodes are sulfur/carbon composite (S/C) cathodes and sulfurized polyacrylonitrile (SPAN) cathodes. In this manuscript, recent advances on S/C and SPAN cathodes in Li-S batteries are comprehensively reviewed. The electrochemical reaction circumstances on S/C and SPAN cathodes are firstly introduced and compared to reveal the working mechanisms of the two types of Li-S batteries. The S/C …


Carbon-Al Interface Effect On The Performance Of Ionic Liquid-Based Supercapacitor At 3 V And 65 OC, Zhen-Zhen Ye, Shu-Ting Zhang, Xin-Qi Chen, Jin Wang, Ying Jin, Chao-Jie Cui, Lei Zhang, Lu-Ming Qian, Gang Zhang, Wei-Zhong Qian Dec 2022

Carbon-Al Interface Effect On The Performance Of Ionic Liquid-Based Supercapacitor At 3 V And 65 OC, Zhen-Zhen Ye, Shu-Ting Zhang, Xin-Qi Chen, Jin Wang, Ying Jin, Chao-Jie Cui, Lei Zhang, Lu-Ming Qian, Gang Zhang, Wei-Zhong Qian

Journal of Electrochemistry

Ionic liquid (IL) electrolyte-based supercapacitors (SCs) have advantages of high operating voltage window, high energy density and nonflammability, as compared to conventional acetonitrile-based organic electrolyte SCs, and are typically suitable for the large-scale energy storage in the era of carbon neutrality full of renewable, but unstable electricity. However, current efforts were concentrated on the study with coin-cell type of IL-SCs, and less has been reported on the pouch type of IL-SCs for a long cycling time yet. To fabricate a reliable SC for the life time test or for the accelerated aging test under high temperature, one should concern the …


Investigating The Electrochemical Behavior Of Dihydropyrrolopyroles For Use As Anodically Coloring Electrochromes, Perry Skiouris, Ally Kisiel, Valentino Sorto, Julia Mauro, Graham Collier Dec 2022

Investigating The Electrochemical Behavior Of Dihydropyrrolopyroles For Use As Anodically Coloring Electrochromes, Perry Skiouris, Ally Kisiel, Valentino Sorto, Julia Mauro, Graham Collier

Symposium of Student Scholars

Electrochromic materials have found widespread use in consumer electronics, energy saving windows, and military applications. They contain unique electronic properties allowing them to undergo a color change in a redox reaction. One classification of these molecules is known as anodically coloring electrochromes (ACEs). When in solution, these compounds are transmissive in the neutral (ground) state and absorb visible light upon oxidation, by the formation of a radical cation, thus making them colored. The focus of this study is the electronic transitions of this radical cation and how chemical modifications to the structures produce a variable color profile. To design prospective …


Synthesis And Electrochemical Characterization Of Alkali Metal Borides As Redox Active Anion Frameworks, Michael R. Shabetai Dec 2022

Synthesis And Electrochemical Characterization Of Alkali Metal Borides As Redox Active Anion Frameworks, Michael R. Shabetai

University of New Orleans Theses and Dissertations

Redox activity in intercalation cathodes is commonly attributed to changes in oxidation states of transition metal ions. Recently, a growing body of evidence revealed that the redox activity of oxygen contributes to the capacity of some known cathodes. We focused on designing an oxygen free intercalation cathode with redox-active anions. In order to overcome the entropic driving force for the decomposition of a charged redox active anion cathode, we looked for chemistries with solid (no gases) possible decomposition products. Additionally, the involvement of anions in a network of covalent bonds with shared electrons was considered as a possible way for …


Elucidation Of Active Site And Mechanism Of Metal Catalysts Supported In Nu-1000, Hafeera Shabbir Dec 2022

Elucidation Of Active Site And Mechanism Of Metal Catalysts Supported In Nu-1000, Hafeera Shabbir

All Dissertations

Advances in extraction of shale oil and gas has increased the production of geographically stranded natural gas (primarily consisting of methane (C1) and ethane (C2)) that is burned on site. A potential utilization strategy for shale gas is to convert it into fuel range hydrocarbons by catalytic dehydrogenation followed by oligomerization by direct efficient catalysts. This work focuses on understanding metal cation catalysts supported on metal-organic framework (MOF) NU-1000 that will actively and selectively do this transformation under mild reaction conditions, while remaining stable to deactivation (via metal agglomeration or sintering). I built computational models validated by experimental methods to …


Visible Light-Assisted Deconstruction/Refunctionalization Of Strained And Unstrained N-Cycloalkylanilines, Elvis Duah Boateng Dec 2022

Visible Light-Assisted Deconstruction/Refunctionalization Of Strained And Unstrained N-Cycloalkylanilines, Elvis Duah Boateng

Graduate Theses and Dissertations

The exploitation of ring strain as a driving force to facilitate chemical reactions is a well-appreciated principle in organic chemistry. Of the strained carbocycles frequently explored in this respect, cyclopropane ring systems have drawn considerably more interest among synthetic chemists than their homolog, the cyclobutane ring systems, even though the strain energy of cyclobutane (26.7 kcal/mol) is similar to that of cyclopropane (27.5 kcal/mol). We have previously developed a [4+2] annulation reaction for the synthesis of aniline-substituted six-membered carbocycles under photoredox catalysis via the oxidative cleavage of N-cyclobutylanilines. The key reaction involved in this method is a ring-opening process of …


Near-Ir Laser Ablation Of Simulated Radiologically Contaminated Oxides On Carbon Steel Feeder Pipes, Thao Viet Do Nov 2022

Near-Ir Laser Ablation Of Simulated Radiologically Contaminated Oxides On Carbon Steel Feeder Pipes, Thao Viet Do

Electronic Thesis and Dissertation Repository

As nuclear power plants age and retire from service, many countries face significant challenges concerning the safe long-term storage and disposal of large volumes of low and intermediate level radioactive wastes (L&ILW). The volumes of metallic waste are of particular concern, as when metal corrodes it produces hydrogen that could lead to pressure build-up in interim storage and disposal. In Canada, a significant fraction of the metallic wastes for Canada Deuterium Uranium (CANDU) nuclear reactors are out-of-core reactor components, such as carbon steel (CS) feeder pipes. The radioactive contamination is expected to be largely confined to the surface oxide layers …


Expanding The Scope Of Clickable Azide-Functionalized Nanoclusters To Include Au144, Johanna A. De Jong Nov 2022

Expanding The Scope Of Clickable Azide-Functionalized Nanoclusters To Include Au144, Johanna A. De Jong

Electronic Thesis and Dissertation Repository

Thiolate-protected Au144 nanoclusters (NCs) are an intriguing member of the gold NC family. Their geometric structure, distinct electrochemical features, and susceptibility to structural rearrangement under the duress of ligand exchange have been studied. However, there are currently no established protocols for surface modification or tuning of their ligand shells post synthesis. Here, the direct synthesis of three regioisomers of azide-modified Au144 NCs with 60 azide moieties, i.e., Au144(SC2H4C6H4-N3)60, is reported, in which the azide functionality is located at the ortho-, meta-, or …


Developing Carbon Quantum Dots As A Luminescent Material And Revisiting Ecl And Led Absolute Measurement Methods, Jonathan Ralph Adsetts Nov 2022

Developing Carbon Quantum Dots As A Luminescent Material And Revisiting Ecl And Led Absolute Measurement Methods, Jonathan Ralph Adsetts

Electronic Thesis and Dissertation Repository

Luminescent materials play increasingly important roles in our lives. Improvements in these materials’ quantum efficiencies (QEs), costs and toxicity can greatly reduce the power consumption, price and environmental damage to the planet, respectively. Carbon quantum dots (CQDs) and luminescent materials exhibiting thermally activated delayed fluorescence (TADF) are two interesting materials in these aspects. Furthermore, measurements on electrochemiluminescence (ECL) and electroluminescence of these luminescent materials can quickly evaluate their performance for many applications. In this thesis, controlled CQD syntheses are revealed beneficial to luminescent materials applications. Their film ECL demonstrated relatively stable anionic and cationic radicals leading to high emission at …


Multi-Electron Reaction-Boosted High Energy Density Batteries: Material And System Innovation, Rui-Qi Guo, Feng Wu, Xin-Ran Wang, Ying Bai, Chuan Wu Nov 2022

Multi-Electron Reaction-Boosted High Energy Density Batteries: Material And System Innovation, Rui-Qi Guo, Feng Wu, Xin-Ran Wang, Ying Bai, Chuan Wu

Journal of Electrochemistry

The continuous development of the global energy structure transformation has put forward higher demands upon the development of batteries. The improvements of the energy density have become one of the important indicators and hot topic for novel secondary batteries. The energy density of existing lithium-ion battery has encountered a bottleneck due to the limitations of material and systems. Herein, this paper introduces the concept and development of multi-electron reaction materials over the past twenty years. Guided by the multi-electron reaction, light weight electrode and multi-ion effect, current development strategies and future trends of high-energy-density batteries are highlighted from the perspective …


Preparation Of Highly-Cyclized Sulfurized Polyacrylonitrile For Lithium-Sulfur Batteries, Xuan Ji, Jia-Yu Wang, An-Bang Wang, Wei-Kun Wang, Ming Yao, Ya-Qin Huang Nov 2022

Preparation Of Highly-Cyclized Sulfurized Polyacrylonitrile For Lithium-Sulfur Batteries, Xuan Ji, Jia-Yu Wang, An-Bang Wang, Wei-Kun Wang, Ming Yao, Ya-Qin Huang

Journal of Electrochemistry

Sulfurized polyacrylonitrile (SPAN) is regarded as an attractive cathode candidate of lithium-sulfur (Li-S) batteries for its non-dissolution mechanism and effective alleviation of polysulfides shuttling issue in Li-S batteries, displaying high utilization of cathode active material, outstanding cycle stability and structural stability. However, the relation between cyclization degree and cycle stability of SPAN is still unveiled. In this work, SPAN-C-V composites were synthesized by co-introduction of CuSO4 and zinc n-ethyl-n-phenyldithiocarbamate (ZDB) in the co-heating of sulfur and polyacrylonitrile. The co-introduction of CuSO4 and ZDB reduced the cyclization reaction onset temperature of PAN while increased the C—C/C=C …


Application Of Artificial Intelligence To Lithium-Ion Battery Research And Development, Zhen-Wei Zhu, Jing-Yi Qiu, Li Wang, Gao-Ping Cao, Xiang-Ming He, Jing Wang, Hao Zhang Nov 2022

Application Of Artificial Intelligence To Lithium-Ion Battery Research And Development, Zhen-Wei Zhu, Jing-Yi Qiu, Li Wang, Gao-Ping Cao, Xiang-Ming He, Jing Wang, Hao Zhang

Journal of Electrochemistry

Lithium-ion batteries (LIBs) have become one of the best solutions to the energy storage issue in modern society. However, the battery materials and device development are both complex, and involve multivariable problems. Traditional trial-and-error approach, which relies on researchers to conduct experiments, has encountered bottlenecks in the improvement of the battery performance. Artificial intelligence (AI) is the most potential technology to deal with this issue due to its powerful high-speed and capabilities of processing massive data. In particular, the capability of machine learning (ML) algorithms in assessing multidimensional data variables and discovering patterns in the sets are expected to assist …


Characterization Of 1d And 2d Materials With Tip-Enhanced Raman Spectroscopy, María Olivia Avilés Oct 2022

Characterization Of 1d And 2d Materials With Tip-Enhanced Raman Spectroscopy, María Olivia Avilés

Electronic Thesis and Dissertation Repository

Carbon-based materials, such as 1D single-walled carbon nanotubes (SWCNT) or 2D graphene, are promising materials for a variety of applications in energy storage, biosensors, and medical imaging applications. Similarly, beyond graphene, 2D transition metal dichalcogenides (TDM) that can have either a metallic or semiconducting character have gained interest for potential applications in electronics and photonics. Specifically, metallic TMDs such as vanadium disulfide (VS2) show potential applications in optoelectronics and lithium-ion batteries. On the other hand, semiconducting TDMs like tungsten disulfide (WS2) show a direct band gap, making them interesting for photovoltaic applications, transistors, or photodetectors. The …


Direct Ink 3d Printing Of Porous Carbon Monoliths For Gas Separations, Marisa L. Comroe, Kurt W. Kolasinski, Dipendu Saha Sep 2022

Direct Ink 3d Printing Of Porous Carbon Monoliths For Gas Separations, Marisa L. Comroe, Kurt W. Kolasinski, Dipendu Saha

Chemistry Faculty Publications

Additive manufacturing or 3D printing is the advanced method of manufacturing monolithic adsorbent materials. Unlike beads or pellets, 3D monolithic adsorbents possess the advantages of widespread structural varieties, low heat and mass transfer resistance, and low channeling of fluids. Despite a large volume of research on 3D printing of adsorbents having been reported, such studies on porous carbons are highly limited. In this work, we have reported direct ink 3D printing of porous carbon; the ink consisted of commercial activated carbon, a gel of poly(4-vinylphenol) and Pluronic F127 as plasticizer, and bentonite as the binder. The 3D printing was performed …


Sensitized Photooxidation Of Prenylated Compounds: Mechanisms Of Downstream Dark Effects And Phototoxicity Priming, Shakeela Jabeen Sep 2022

Sensitized Photooxidation Of Prenylated Compounds: Mechanisms Of Downstream Dark Effects And Phototoxicity Priming, Shakeela Jabeen

Dissertations, Theses, and Capstone Projects

This thesis consists of four chapters as detailed below.

Chapter 1 discusses a singlet oxygen priming mechanism. Airborne singlet oxygen derived from photosensitization of triplet dioxygen is shown to react with an alkene surfactant (8-methylnon-7-ene-1 sulfonate) leading to ‘ene’ hydroperoxides that in the dark inactivate planktonic E. coli. The ‘ene’ hydroperoxide photoproducts are not toxic on their own, but they become toxic after the bacteria are pretreated with singlet oxygen. The total quenching rate constant (kT) of singlet oxygen of the alkene surfactant was measured to be 1.1 × 106 M1 s− …


Visible Light Photocatalysis Of Organic Reactions In H2o, Sankarsan Biswas Sep 2022

Visible Light Photocatalysis Of Organic Reactions In H2o, Sankarsan Biswas

Dissertations, Theses, and Capstone Projects

Visible-light photocatalysis in H2O provides an attractive, green alternative to typical organic synthesis, which often involves toxic solvents, metal catalysts, and large energy demands. Hence, there is a growing need for an efficient photocatalytic methods that use either aqueous media as a solvent or can proceed solvent-free. However, commercially available photocatalysts do not work well for aqueous photocatalysis. Supramolecular systems in particular have been explored recently to address these issues associated with aqueous photocatalysis. Chapter 1 will review recent advances in aqueous supramolecular photocatalysis with examples of different supramolecular systems and how they have addressed some of the …


Engineering Rare-Earth Based Color Centers In Wide Bandgap Semiconductors For Quantum And Nanoscale Applications, Gabriel I. López-Morales Sep 2022

Engineering Rare-Earth Based Color Centers In Wide Bandgap Semiconductors For Quantum And Nanoscale Applications, Gabriel I. López-Morales

Dissertations, Theses, and Capstone Projects

For many years, atomic point-defects have been readily used to tune the bulk properties of solid-state crystalline materials, for instance, through the inclusion of elemental impurities (doping) during growth, or post-processing treatments such as ion bombardment or high-energy irradiation. Such atomic point-defects introduce local ‘incompatible’ chemical interactions with the periodic atomic arrangement that makes up the crystal, resulting for example in localized electronic states due to dangling bonds or excess of electrons. When present in sufficient concentrations, the defects interact collectively to alter the overall bulk properties of the host material. In the low concentration limit, however, point-defects can serve …


Growth, Optimization, And Characterization Of Topological Insulator Nanostructures By Molecular Beam Epitaxy, Ido Levy Sep 2022

Growth, Optimization, And Characterization Of Topological Insulator Nanostructures By Molecular Beam Epitaxy, Ido Levy

Dissertations, Theses, and Capstone Projects

Topological insulators (TIs) have been the subject of much research since their discovery in 2009. The unique band structure of the TIs makes them attractive in research of exotic physical phenomena, such as the realization of the quantum anomalous Hall effect, as well as novel applications, including quantum computing, spintronics, and more. From a crystal growth perspective, their van-der-Waals structure also provides new opportunities, for example, by enabling the growth on a large selection of substrates. This thesis presents the growth of three-dimensional TI layers, heterostructures and magnetic TIs by molecular beam epitaxy (MBE). First, we show the improvement of …


Fabrication Of Gold Nanoraspberry Arrays By Soft Lithography, Christy Yu-Qing Xie Aug 2022

Fabrication Of Gold Nanoraspberry Arrays By Soft Lithography, Christy Yu-Qing Xie

Undergraduate Student Research Internships Conference

Nanostructures and nanoparticles have garnered increasing interest over the past decade due to their unique properties and applications. These properties include localized surface plasmon resonance (LSPR) and allow for surface modification. We can tune these properties depending on the nanoparticle’s size, shape, and geometry.

This work aims to fabricate plasmonic platforms through patterning gold nanoparticles (raspberries) by microcontact printing, a simple and cost-effective soft lithography technique. This is done through large-scale patterning using polydimethylsiloxane (PDMS) stamps to pattern an adhesion template and spatially guide the adsorption of gold nanoparticles (AuNPs).