Recent Advances In Exploring Highly Active & Durable Pgm-Free Oxygen Reduction Catalysts,
2023
College of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, PR China
Recent Advances In Exploring Highly Active & Durable Pgm-Free Oxygen Reduction Catalysts, Yuan Li, Miao-Ying Chen, Bang-An Lu, Jia-Nan Zhang
Journal of Electrochemistry
In order to reduce the considerable usage of expensive but scarce platinum at the cathode in proton exchange membrane fuel cells (PEMFCs), it is necessary to pursue alternatives to platinum. The most promising platinum group metal (PGM)-free catalysts for oxygen reduction reaction (ORR) are atomically dispersed, and nitrogen-coordinated metal site catalysts denoted as M-N-C (M = Fe, Co, or Mn, etc.). Over the last few decades, there have been great advances in these catalysts with high ORR activity and promising initial fuel cell performance approaching traditional Pt/C catalysts. However, the stability of these highly active Fe-N-C catalysts under practical fuel …
Electrochemical Oxidation Of Ethylene On Palladium Electrode,
2023
Chemistry Department, Chinese University of Hong Kong, Hong Kong 999077, China
Electrochemical Oxidation Of Ethylene On Palladium Electrode, Wei-Xing Wu, Ying Wang
Journal of Electrochemistry
The electrochemical oxidation of C2H4 is attracting increasing attention due to its vast potential market. The current electrochemical methods rely on the use of redox mediators, which may produce corrosive intermediates, while direct oxidation is still limited by its low activity and selectivity. Herein, we conducted electrochemical studies to obtain mechanistic insights into the benchmark Pd catalyst. The generated Pd(II) could be the active site for C2H4 oxidation. By designing the pulse sequence, we found the ratio of strongly and weakly adsorbed C2H4 on Pd to be 0.3:1. The result we …
Supperlattice-Like Structure: Ordered Mass Transfer Endowing High Quality Output Of Fuel Cell,
2023
a Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, School of Chemistry and Chemical Engineering, Chongqing University, Chongqing, China
Supperlattice-Like Structure: Ordered Mass Transfer Endowing High Quality Output Of Fuel Cell, Jian Wang, Wen-Hui Xuan, Qian He, Jing-Xia Jiang, Yuan-Yuan Zhou, Yao Nie, Qiang Liao, Min-Hua Shao, Wei Ding, Zi-Dong Wei
Journal of Electrochemistry
The current or voltage fluctuation in fuel cell operation is harmful to the fuel cell system and power application equipment. Here, we report a technique to eliminate such a fluctuation by the aid of new type of catalysts, superlattice-like mesoporous PtCo catalysts. The current fluctuation in fuel cells catalyzed by two invented catalysts are fixed at as low as 25 mA·cm−2 with a power of 0.75 W·cm−2 or 120 mA·cm−2 with a power of 1.01 W·cm−2, and no noticeable current decay was detected over 100 h. By contrast, a …
Magnetic Interactions In Open-Shell Conjugated Polymers,
2023
University of Southern Mississippi
Magnetic Interactions In Open-Shell Conjugated Polymers, Michael Steelman
Dissertations
Most materials are closed shell in which every electron participates in a bond, resulting in unremarkable magnetometry signatures and functionalities. While rare, modern technologies rely on magnetic materials in which unpaired electrons are localized to inorganic atomic centers. In recent decades, a collection of organic open-shell π-conjugated molecules have shown magnetic ordering, albeit at exceedingly low temperatures; a result of weak noncovalent intermolecular interactions limiting long range electronic exchange. Thus, practically applicable sp orbital magnetism that persists at or above room temperature remains a grand challenge for chemistry and physics. Despite the wide variety of chemical structures afforded by organic …
Development Of Battery Materials To Function As Corrosion Protection On Car Body Plates,
2023
Institut Teknologi Sepuluh Nopember
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
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 …
Potential Of Biduri Fiber (Calotropis Gigantea) As Material For Oil Spill Absorbent,
2023
Balai Besar Tekstil
Potential Of Biduri Fiber (Calotropis Gigantea) As Material For Oil Spill Absorbent, Anne Sukmawati, Wulan Septiani
Journal of Materials Exploration and Findings
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 …
Influence Of Synthesis Conditions On The Physicochemical And Electrocatalytic Properties Of Non-Stoichiometric Ba2sr2la2ti4o12 Perovskites,
2023
Institute of Electrochemistry and Energy Systems Acad. Evgeni Budevski, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl 10, 1113 Sofia, Bulgaria
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,
2023
Murray State University
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 …
Synthesis Of A Novel Terbium(Iii) Complex For Application In Metal Nanoparticle Surface Modification,
2023
Belmont University
Synthesis Of A Novel Terbium(Iii) Complex For Application In Metal Nanoparticle Surface Modification, Lauralee E. Hurst, Davon Ferrara, Justin Stace
Science University Research Symposium (SURS)
Lanthanide ions, such as terbium(III), exhibit bright luminescence when bound to organic ligands which strongly absorb light. This property has been used in creating chemical sensors or luminescent tags for microscopy. Complexes centered with terbium(III) exhibit a yellow-green luminescence upon excitation by shortwave ultraviolet light. In this work, a bifunctional ligand, 4-mercaptobenzoic acid (4mba), was chosen to selectively coordinate terbium(III) to the oxygens of the acid functional group, leaving the thiol group available for another compound. Thiol groups are effectively used in surface coordination to noble metal nanoparticles (NP). In efforts to create a novel 4mba-terbium(III)-NP system, a one pot …
Functionalizing Metal-Organic Super-Containers (Moscs) For Selective Anion Recognition,
2023
University of South Dakota
Functionalizing Metal-Organic Super-Containers (Moscs) For Selective Anion Recognition, Hanying Li
Dissertations and Theses
Anions are ubiquitous in Nature and play critical roles in both chemistry and biology. Biologically important molecules like enzymes, DNA, and ATP (adenosine triphosphate) are either anionic or contain negatively charged regions. Inorganic anions such as Cl- and HCO3- play essential roles in various physiological, environmental, and technological processes. Compared to cations, anions have larger ionic radii and more diffuse charge distribution, resulting in weaker electrostatic interactions. Developing synthetic receptors for controlled anion recognition is vital but poses significant challenges. Recent decades have shown remarkable progress in anion recognition, yielding diverse synthetic receptors with promising binding abilities. However, traditional approaches …
Structural And Functional Modulation Of Metal-Organic Supercontainers (Moscs) And Their Applications In Supramolecular Catalysis,
2023
University of South Dakota
Structural And Functional Modulation Of Metal-Organic Supercontainers (Moscs) And Their Applications In Supramolecular Catalysis, Shrijana Dc
Dissertations and Theses
Metal-organic supercontainers (MOSCs), a breakthrough development in our laboratory since 2012, have emerged as promising enzyme mimics, showcasing their prowess in encapsulating guest molecules and catalyzing confined chemical reactions. The intrigue surrounding MOSCs stems from their extraordinary traits, encompassing multiple binding domains, high stability, large surface area, tunable pore size, and structural modularity. Primarily comprising sulfonylcalix[4]arenes, divalent metal ions, and carboxylate linkers, MOSCs' quintessential architecture comprises both endo- and exo- nano-cavities, amenable to guest interaction, with geometry and functionality manipulation achievable through precise precursor selection. Nonetheless, early MOSC models exhibit limited reactivity, often necessitating more potent nucleophiles or electrophiles. This …
Diethoxycarbonyl-Bodipys As Heavy-Atom-Free Photosensitizers For Holographic Recording In Cellulose Acetate Photopolymer,
2023
Technological University Dublin
Diethoxycarbonyl-Bodipys As Heavy-Atom-Free Photosensitizers For Holographic Recording In Cellulose Acetate Photopolymer, Aimee Sheehan, Tatsiana Mikulchyk, Catherine S.P. De Castro, Safakath Karuthedath, Wejdan Althobaiti, Metodej Dvoracek, Sabad-E Gul, Hugh Byrne, FréDéRic Laquai, Izabela Naydenova, Mikhail Filatov
Articles
A series of new heavy-atom-free photosensitizers based on 2,6-diethoxycarbonyl-BODIPY scaffold was designed and applied for holographic recording in a photopolymerizable material. Photoinduced electron transfer between the BODIPY and meso-aryl subunits, followed by the formation of BODIPY triplet excited states via spin-orbit charge transfer intersystem crossing (SOCT-ISC) was studied by steady-state and ultrafast pump-probe transient optical spectroscopy. Highly efficient photosensitization was observed for dyads bearing pyrene and anthracene substituents, which exhibited singlet oxygen generation quantum yields () of up to 94%. Charge transfer and SOCT-ISC were observed in non-polar solvent (toluene) due to the increased electron accepting ability of the diethoxycarbonyl-BODIPY. …
Outstanding Advantages, Current Drawbacks, And Significant Recent Developments In Mechanochemistry: A Perspective View,
2023
Old Dominion University
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 …
Structural, Thermal, Optical, And Mechanical Properties Of Composite Films Developed From The Button Mushroom (Agaricus Bisporus)-Sourced High Molecular Weight Chitosan And Potato Starch,
2023
Technological University Dublin, Ireland
Structural, Thermal, Optical, And Mechanical Properties Of Composite Films Developed From The Button Mushroom (Agaricus Bisporus)-Sourced High Molecular Weight Chitosan And Potato Starch, Buliyaminu A. Alimi, Monjural Hoque, Shivani Pathania, Jude Wilson, Brendan Duffy, Jesus Maria Frias
Articles
Films were fabricated using the button mushroom (Agaricus bisporus) sourced high molecular weight chitosan with or without potato starch using the casting method. Glycerol was used as the plasticizer. Chitosan content in the film-forming solution (FFS) was varied (0.5, 0.75 and 1.0% w/v of FFS) while potato starch (1.0% of FFS) and glycerol (25% of the total solid content in the solution) contents were not varied. The control sample contained only chitosan (1.0% of the FFS) and glycerol. The effect of increasing the content of chitosan on the rheological properties of FFS and the properties of the films were investigated. …
Synthesis And Self-Assembling Properties Of Carbohydrate- And Diarylethene-Based Photoswitchable Molecular Gelators,
2023
Old Dominion University
Synthesis And Self-Assembling Properties Of Carbohydrate- And Diarylethene-Based Photoswitchable Molecular Gelators, Pramod Aryal, Joedian Morris, Surya B. Adhikari, Jonathan Bietsch, Guijun Wang
Chemistry & Biochemistry Faculty Publications
Carbohydrate-based low-molecular-weight gelators are interesting new materials with many potential applications. These compounds can be designed to include multiple stimuli-responsive functional groups. In this study, we designed and synthesized several chemically responsive bola-glycolipids and dimeric carbohydrate- and diarylethene-based photoswitchable derivatives. The dimeric glycolipids formed stable gels in a variety of solvent systems. The best performing gelators in this series contained decanedioic and dithienylethene (DTE) spacers, which formed gels in eight and nine of the tested solvents, respectively. The two new DTE-containing esters possessed interesting photoswitching properties and DTE derivative 7 was found to have versatile gelation properties in many solvents, …
Synthesis Of A Series Of Trimeric Branched Glycoconjugates And Their Applications For Supramolecular Gels And Catalysis,
2023
Old Dominion University
Synthesis Of A Series Of Trimeric Branched Glycoconjugates And Their Applications For Supramolecular Gels And Catalysis, Jonathan Bietsch, Anji Chen, Dan Wang, Guijun Wang
Chemistry & Biochemistry Faculty Publications
Carbohydrate-derived molecular gelators have found many practical applications as soft materials. To better understand the structure and molecular gelation relationship and further explore the applications of sugar-based gelators, we designed and synthesized eight trimeric branched sugar triazole derivatives and studied their self-assembling properties. These included glucose, glucosamine, galactose, and maltose derivatives. Interestingly, the gelation properties of these compounds exhibited correlations with the peripheral sugar structures. The maltose derivative did not form gels in the tested solvents, but all other compounds exhibited gelation properties in at least one of the solvents. Glucose derivatives showed superior performance, followed by glucosamine derivatives. They …
Silica Particles Convert Thiol-Containing Molecules To Disulfides,
2023
Stanford University
Silica Particles Convert Thiol-Containing Molecules To Disulfides, Yangjie Li, Kurt W. Kolasinski, Richard N. Zare
Chemistry Faculty Publications
Synthetic amorphous silica is a common food additive and a popular cosmetic ingredient. Mesoporous silica particles are also widely studied for their potential use in drug delivery and imaging applications because of their unique properties, such as tunable pore sizes, large surfaces areas, and assumed biocompatibility. Such a nanomaterial, when consisting of pure silicon dioxide, is generally considered to be chemically inert, but in this study, we showed that oxidation yields for different compounds were facilitated by simply incubating aqueous solutions with pure silica particles. Three thiol-containing molecules, L-cysteine, glutathione, and D-penicillamine, were studied separately, and it was found that …
Computational Investigation Of The Ionization Potential Of Lead Sulfide Quantum Dots,
2023
Claremont Colleges
Computational Investigation Of The Ionization Potential Of Lead Sulfide Quantum Dots, Jessica Beyer
Scripps Senior Theses
The purpose of this work was to determine the impact of quantum dot size on ionization potential and to determine how the presence of carbonyl-based ligands affect the ionization potential of lead sulfide quantum dot systems. Ionization potential (IP) is defined as the energy required to remove an electron from an atom, molecule, or material. IP helps scientists determine how reactive the material of interest is, which is crucial information when manufacturing nanomaterials. Accurate quantum chemical calculations of ionization potential are challenging due to the computational cost associated with the numerical solution of the Dyson equation. In this work, the …
Intergranular And Pitting Corrosion Mechanisms Of Sensitized Aluminum Alloy Aa5083,
2023
The University of Akron
Intergranular And Pitting Corrosion Mechanisms Of Sensitized Aluminum Alloy Aa5083, Clayton Egleston
Williams Honors College, Honors Research Projects
The motivation and objectives of this project is to examine the mechanisms of intergranular corrosion (IGC) and pitting corrosion of sensitized AA5083. In this regard, different characterization techniques were used, including optical analysis of microstructure, cyclic potentiodynamic polarization with Tafel fitting, electrochemical impedance spectroscopy with electrical equivalent circuit (EEC) fitting, and potentiostatic current transient monitoring. The transition from IGC to pitting corrosion occurs when the grain boundaries become saturated with the β-phase (Mg2Al3). It was found that AA5083 becomes more vulnerable to pitting corrosion as the degree of sensitization increases.
Nanostructured Ternary Nickel-Based Mixed Anionic (Telluro)-Selenide As A Superior Catalyst For Oxygen Evolution Reaction,
2023
Missouri University of Science and Technology
Nanostructured Ternary Nickel-Based Mixed Anionic (Telluro)-Selenide As A Superior Catalyst For Oxygen Evolution Reaction, Ibrahim Munkaila Abdullahi, Siby Thomas, Alessio Gagliardi, Mohsen Asle Zaeem, Manashi Nath
Chemistry Faculty Research & Creative Works
Developing Protocols for Designing High-Efficiency, Durable, Cost-Effective Electrocatalysts for Oxygen Evolution Reaction (OER) Necessitates Deeper Understanding of Structure–property Correlation as a Function of Composition. Herein, It Has Been Demonstrated that Incorporating Tellurium into Binary Nickel Chalcogenide (NiSe) and Creating a Mixed Anionic Phase Perturbs its Electronic Structure and Significantly Enhances the OER Activity. a Series of Nanostructured Nickel Chalcogenides Comprising a Layer-By-Layer Morphology Along with Mixed Anionic Ternary Phase Are Grown in Situ on Nickel Foam with Varying Morphological Textures using Simple Hydrothermal Synthesis Route. Comprehensive X-Ray Diffraction, X-Ray Photoelectron Spectroscopy, and in Situ Raman Spectroscopy Analysis Confirms the Formation …
