Physical Sciences and Mathematics Commons^™

Premade Nanoparticle Films For The Synthesis Of Vertically Aligned Carbon Nanotubes, Abdul Hoque, Ahamed Ullah, Beth S. Guiton, Noe T. Alvarez

Chemistry Faculty Publications

Carbon nanotubes (CNTs) offer unique properties that have the potential to address multiple issues in industry and material sciences. Although many synthesis methods have been developed, it remains difficult to control CNT characteristics. Here, with the goal of achieving such control, we report a bottom-up process for CNT synthesis in which monolayers of premade aluminum oxide (Al₂O₃) and iron oxide (Fe₃O₄) nanoparticles were anchored on a flat silicon oxide (SiO₂) substrate. The nanoparticle dispersion and monolayer assembly of the oleic-acid-stabilized Al₂O₃ nanoparticles were achieved using 11-phosphonoundecanoic acid …

Development Of Novel Adsorbent For Industrial Waste Water Treatment, Islam M. Al-Akraa, Hassan M. Shehata Eng, Dalia A. Ali Eng., Hoda A. Elsawy Dr

Chemical Engineering

The main objective of this research project is to perform some experimental procedures to inform the ability of the novel adsorbent used in this project. The chemical modification of the adsorbent is the chemical oxidation of pure powder chitosan using some specific redox pairs which are potassium dichromate and sodium bisulphite. After preparing the modified chitosan, there are some parameters that must be discussed during the adsorption process. The first parameter is the time parameter, showing experimentally the optimum time for adsorption under certain conditions by collecting values of absorbance and concentration of thymol blue adsorbed after the process from …

Preparation And Characterization Of Ruthenium-Gold Raman-Active Catalytic Surfaces, Thang Nguyen

Student Scholar Symposium Abstracts and Posters

Heterogeneous reactions at the gas-solid interface play a major role in many important industrial and environmental processes. These reactions typically rely on metal surfaces, to act as a catalyst between gas phase reactants and products. The catalysts lower the transition state barrier in the formation of the products. The mechanisms of reactions on catalysts is often not fully known due to the difficulty of observing the bond breakage and formation between gaseous molecules at the interface. One method in which the catalytic mechanism can be studied is by using Raman Spectroscopy. However, one drawback of this method is the fact …

Method Of Increasing Mass Transfer Rate Of Acid Gas Scrubbing Solvents, Joseph E. Remias, Cameron A. Lippert, Kunlei Liu

Center for Applied Energy Research Faculty Patents

A method of increasing the overall mass transfer rate of acid gas scrubbing solids is disclosed. Various catalyst compounds for that purpose are also disclosed.

Atomically Dispersed Pd On Nanodiamond/Graphene Hybrid For Selective Hydrogenation Of Acetylene, Fei Huang, Yuchen Deng, Yunlei Chen, Xiangbin Cai, Mia Peng, Zhimin Jia, Pengju Ren, Dequan Xiao, Xiaodong Wen, Ning Wang, Hongyang Liu, Ding Ma

Chemistry and Chemical Engineering Faculty Publications

An atomically dispersed palladium (Pd) catalyst supported onto a defective nanodiamond-graphene (ND@G) is reported here for selective hydrogenation of acetylene in the presence of abundant ethylene. The catalyst exhibits remarkable performance for the selective conversion of acetylene to ethylene: high conversion (100%), ethylene selectivity (90%), and good stability (i.e., steady for at least 30 hours). The unique struc-ture of the catalyst (i.e., atomically dispersion of Pd atoms on graphene through Pd-C bond anchoring) ensure the facile desorption of ethylene against the over-hydrogenation of ethylene to undesired ethane, which is the key for the outstanding selectivity of the catalyst.

Visible Light Generation Of High-Valent Corrole-Manganese(V)-Oxo Intermediates And Biomimetic Studies Of The Oxidation Of Organic Sulfides Catalyzed By Manganese Corroles With Iodobenzene Diacetate, Davis Ray Ranburger

Masters Theses & Specialist Projects

High-valent transition metal-oxo intermediates play essential roles as active oxidizing species in enzymatic and biomimetic catalytic systems. Extensive research has been conducted on a variety of transition metal catalysts being studied as models for the ubiquitous cytochrome P450 enzymes. In doing so, the production of enzyme-like oxidation catalysts and probing studies on the sophisticated oxygen atom transfer mechanism are taking place.

In this work, visible-light irradiation of highly-photo-labile corrole-manganese(IV) bromates and chlorates was studied in two corrole systems with differing electronic environments, i.e. 5,10,15-trisphenylcorrole (H3TPC) and 5,10,15- tris(pentafluorophenyl)corrole (H3TPFC). In both systems, homolytic cleavage of the O- …

Synergistic Interactions Of H2 And N2 With Molten Gallium In The Presence Of Plasma, Maria L. Carreon, Daniel F. Jaramillo-Cabanzo, Indira Chaudhuri, Madhu Menon, Mahendra K. Sunkara

Physics and Astronomy Faculty Publications

The present study examines the interaction of hydrogen and nitrogen plasmas with gallium in an effort to gain insights into the mechanisms behind the synergetic effect of plasma and a catalytic metal. Absorption/desorption experiments were performed, accompanied by theoretical-computational calculations. Experiments were carried out in a plasma-enhanced, Ga-packed, batch reactor and entailed monitoring the change in pressure at different temperatures. The results indicated a rapid adsorption/dissolution of the gas into the molten metal when gallium was exposed to plasma, even at a low temperature of 100 °C. The experimental observations, when hydrogen was used, indicate that gallium acts as a …

Catalytic Oxidation And Depolymerization Of Lignin In Aqueous Ionic Liquid, Lalitendu Das, Siquan Xu, Jian Shi

Biosystems and Agricultural Engineering Faculty Publications

Lignin is an integral part of the plant cell wall, which provides rigidity to plants, also contributes to the recalcitrance of the lignocellulosic biomass to biochemical and biological deconstruction. Lignin is a promising renewable feedstock for aromatic chemicals; however, an efficient and economic lignin depolymerization method needs to be developed to enable the conversion. In this study, we investigated the depolymerization of alkaline lignin in aqueous 1-ethyl-3-methylimidazolium acetate [C₂C₁Im][OAc] under oxidizing conditions. Seven different transition metal catalysts were screened in presence of H₂O₂ as oxidizing agent in a batch reactor. CoCl₂ and …

Enhancements In Mass Transfer For Carbon Capture Solvents Part I: Homogeneous Catalyst, Leland R. Widger, Moushumi Sarma, Jonathan J. Bryant, David S. Mannel, Jesse G. Thompson, Cameron A. Lippert, Kunlei Liu

Center for Applied Energy Research Faculty and Staff Publications

The novel small molecule carbonic anhydrase (CA) mimic [Co^III(Salphen-COO⁻)Cl]HNEt₃ (1), was synthesized as an additive for increasing CO₂ absorption rates in amine-based post-combustion carbon capture processes (CCS), and its efficacy was verified. 1 was designed for use in a kinetically slow but thermally stable blended solvent, containing the primary amines 1-amino-2-propanol (A2P) and 2-amino-2-methyl-1-propanol (AMP). Together, the A2P/AMP solvent and 1 reduce the overall energy penalty associated with CO₂ capture from coal-derived flue gas, relative to the baseline solvent MEA. 1 is also effective at increasing absorption kinetics of kinetically fast solvents, such …

Mo2c/Cnt: An Efficient Catalyst For Rechargeable Li–Co2 Batteries, Yuyang Hou, Jiazhao Wang, Lili Liu, Yuqing Liu, Shulei Chou, Dongqi Shi, Hua-Kun Liu, Yu-Ping Wu, Weimin Zhang, Jun Chen

Australian Institute for Innovative Materials - Papers

The rechargeable Li-CO2 battery is a novel and promising energy storage system with the capability of CO2 capture due to the reversible reaction between lithium ions and carbon dioxide. Carbon materials as the cathode, however, limit both the cycling performance and the energy efficiency of the rechargeable Li-CO2 battery, due to the insulating Li2CO3 formed in the discharge process, which is difficult to decompose in the charge process. Here, a Mo2C/carbon nanotube composite material is developed as the cathode for the rechargeable Li-CO2 battery and can achieve high energy efficiency (77%) and improved cycling performance (40 cycles). A related mechanism …

New Urjc-1 Material With Remarkable Stability And Acid-Base Catalytic Properties, Pedro Leo, Ferdnando Martinez, Guillermo Calleja, David Briones, Lukasz Wojtas

Chemistry Faculty Publications

Emerging new metal-organic structures with tunable physicochemical properties is an exciting research field for diverse applications. In this work, a novel metal-organic framework Cu(HIT)(DMF)_0.5, named URJC-1, with a three-dimensional non-interpenetrated utp topological network, has been synthesized. This material exhibits a microporous structure with unsaturated copper centers and imidazole–tetrazole linkages that provide accessible Lewis acid/base sites. These features make URJC-1 an exceptional candidate for catalytic application in acid and base reactions of interest in fine chemistry. The URJC-1 material also displays a noteworthy thermal and chemical stability in different organic solvents of different polarity and boiling water. Its catalytic …

Self-Assembled 3d Foam-Like Nico2o4 As Efficient Catalyst For Lithium Oxygen Batteries, Lili Liu, Jun Wang, Yuyang Hou, Jun Chen, Hua-Kun Liu, Jiazhao Wang, Yu-Ping Wu

Australian Institute for Innovative Materials - Papers

A self-assembled 3D foam-like NiCo2O4 catalyst has been synthesized via a simple and environmental friendly approach, wherein starch acts as the template to form the unique 3D architecture. Interestingly, when employed as a cathode for lithium oxygen batteries, it demonstrates superior bifunctional electrocatalytic activities toward both the oxygen reduction reaction and the oxygen evolution reaction, with a relatively high round-trip efficiency of 70% and high discharge capacity of 10 137 mAh g-1 at a current density of 200 mA g-1, which is much higher than those in previously reported results. Meanwhile, rotating disk electrode measurements in both aqueous and nonaqueous …

Developing Catalysts For Improving Direct Amide Formation, Courtney Carley

Summer Research

The widespread occurrence of the amide functional group in the pharmaceutical industry and its prevalence in biological structures such as proteins illustrate the huge impact that amides have on our daily lives. Current methods of forming amides are expensive and harmful to the environment, so there is a need for the development of greener processes for the formation of amides. The first objective of this research is to synthesize catalysts for the direct formation of amides from carboxylic acids and amines. Previously developed catalysts for this transformation are not active enough, and are thus rarely used. The new catalysts to …

A Light-Assisted, Polymeric Water Oxidation Catalyst That Selectively Oxidizes Seawater With A Low Onset Potential, Jun Chen, Pawel W. Wagner, Lei Tong, Danijel Boskovic, Weimin Zhang, David L. Officer, Gordon G. Wallace, Gerhard F. Swiegers

Australian Institute for Innovative Materials - Papers

Vapour phase polymerisation (vpp) of PEDOT to incorporate high levels of a sulphonated manganese porphyrin yields a vivid green conducting polymer that, under illumination, catalyzes selective oxidation of water from seawater from ca. 0.40 V (vs. NHE; Pt counter electrode) without observable chlorine formation. This onset potential is comparable to that of certain metal oxide semiconductors that achieve higher photocurrents but are not capable of selectively oxidising the water in seawater.

Synthesis Of Bipyridine-Derived Iron Catalysts For Hydrogenation, Jack Elder

Summer Research

Industrially, alkene and carbonyl hydrogenation reactions are catalyzed by iridium, rhodium and ruthenium-centered catalysts. These highly toxic metals are very expensive, both to attain and to dispose of after degradation. This ongoing research seeks to investigate cleaner and more economical alternative catalysts by synthesizing and testing a bipyridine-derived iron catalyst utilizing the unconventional ligand-assisted heterolytic cleavage of hydrogen mechanism to facilitate double bond hydrogenation. In the time allotted, this segment of research sought to synthesize the two catalyst ligands 6-hydroxy-2,2’-bipyrdine and 6,6’-dihydroxy-2,2’-bipyridine, and to model ligand-iron attachment using commercially available iron complexes. The former of the two ligands was synthesized …

Photochemical Oxidation Studies Of Porphyrin Ruthenium Complexes, Eric Vanover

Masters Theses & Specialist Projects

In nature, transition metal containing enzymes display many biologically important, attractive and efficient catalytic oxidation reactions. Many transition metal catalysts have been designed to mimic the predominant oxidation catalysts in nature, namely, the cytochrome P450 enzymes. Ruthenium porphyrin complexes have been the center of this research and have successfully been utilized, as catalysts, in major oxidation reactions, such as the hydroxylation of alkanes. The present work focuses on photocatalytic studies of aerobic oxidation reactions with well characterized ruthenium porphyrin complexes.

The photocatalytic studies of aerobic oxidation reactions of hydrocarbons The photocatalytic studies of aerobic oxidation reactions of hydrocarbons catalyzed by …

Chromium Salen, Gráinne Hargaden, Pier Giorgio Cozzi

Articles

No abstract provided.

Fabrication And Catalytic Property Of Cerium Oxide Nanomaterials, Keren Jiang

Department of Chemistry: Dissertations, Theses, and Student Research

Cerium oxide, or ceria (CeO_x: x = 1.5 to 2), has been widely used as a heterogeneous catalyst. Ceria has several properties make it high catalytic active: the fluctuating valence of cerium, the high oxygen storage capacity and high oxygen mobility in the nonstoichiometric ceria. With the high abundance of cerium on earth crust, ceria is a highly effective alternative of the noble metal catalysts. Research has been focused on designing nanostructured ceria and ceria related materials in recent years. The catalytic activity of ceria can be enhanced by the nanoscale effect which can be applied for various …

Carbon Nanotube Architectures As Catalyst Supports For Proton Exchange Membrane Fuel Cells, Weimin Zhang, Peter Sherrell, Andrew I. Minett, Joselito M. Razal, Jun Chen

Faculty of Science - Papers (Archive)

Catalyst support materials exhibit great influence on the performance and durability of proton exchange membrane (PEM) fuel cells. This minireview article summarises recent developments into carbon nanotube-based support materials for PEM fuel cells, including the membrane electrode assembly (MEA). The advantages of using CNTs to promote catalyst performance and stability, a perspective on research directions and strategies to improve fuel cell performance and durability are discussed. It is hoped that this mini-review will act as a conduit for future developments in catalyst supports and MEA design for PEM fuel cells.

Immobilization Of The Aminopeptidase From Aeromonas Proteolytica On Mg2+/Al3+ Layered Double Hydroxide Particles, Steven T. Frey, Stephanie L. Guilmet, Richard G. Egan Iii, Alyssa Bennett, Sarah R. Soltau, Richard C. Holz

Chemistry Faculty Research and Publications

A novel biomaterial formed by the immobilization of the Aminopeptidase from Aeromonas proteolytica (AAP) on synthetic Mg²⁺ and Al³⁺ ion-containing layered double hydroxide (LDH) particles was prepared. Immobilization of AAP on the LDH particles in a buffered, aqueous mixture is rapid such that the maximum loading capacity, 1 × 10⁻⁹ moles of AAP/mg LDH, is achieved in a few minutes. X-ray powder diffraction of LDH samples before and after treatment with AAP indicates that the enzyme does not intercalate between the layers of LDH, but instead binds to the surface. Treatment of AAP/LDH with various amounts of …

A Bio-Inspired Molecular Water Oxidation Catalyst For Renewable Hydrogen Generation: An Examination Of Salt Effects, Robin Brimblecombe, Miriam Rotstein, Annette Koo, G Charles Dismukes, Gerhard F. Swiegers, Leone Spiccia

Faculty of Science - Papers (Archive)

Most transport fuels are derived from fossil fuels, generate greenhouse gases, and consume significant amounts of water in the extraction, purification, and/or burning processes. The generation of hydrogen using solar energy to split water, ideally from abundant water sources such as sea water or other non-potable sources, could potentially provide an unlimited, clean fuel for the future. Solar, electrochemical water splitting typically combines a photoanode at which water oxidation occurs, with a cathode for proton reduction to hydrogen. In recent work, we have found that a bioinspired tetra-manganese cluster catalyzes water oxidation at relatively low overpotentials (0.38 V) when doped …

A Bio-Inspired Molecular Catalyst That Selectively Catalyzes Water Oxidation In Seawater, Without Significant Chlorine Formation, Robin Brimblecombe, G. Charles Dismukes, Gerhard F. Swiegers, Leone Spiccia

Faculty of Science - Papers (Archive)

Most transport fuels are derived from fossil fuels, generate greenhouse gases, and consume significant amounts of water in the extraction, purification, and/or burning processes. The generation of hydrogen using solar energy to split water, ideally from sea water or other non-potable sources, could potentially provide an unlimited, clean fuel for the future. Solar, electrochemical water splitting typically combines a photoanode at which water oxidation occurs, with a cathode for proton reduction to hydrogen. In recent work we have found that a bioinspired tetra-manganese cluster catalyzes water oxidation at relatively low overpotentials (0.38 V) when doped into a Nafion proton conduction …

Kinetic Evaluation Of Highly Active Supported Gold Catalysts Prepared From Monolayer-Protected Clusters: An Experimental Michaelis-Menten Approach For Determining The Oxygen Binding Constant During Co Oxidation Catalysis, Cormac G. Long, John D. Gilbertson, G. Vijayaraghavan, K. J. Stevenson, Christopher J. Pursell, Bert D. Chandler

Chemistry Faculty Research

Thiol monolayer-protected Au clusters (MPCs) were prepared using dendrimer templates, deposited onto a high-surface-area titania, and then the thiol stabilizers were removed under H2/N2. The resulting Au catalysts were characterized with transmission electron microscopy, X-ray photoelectron spectroscopy, and infrared spectroscopy of adsorbed CO. The Au catalysts prepared via this route displayed minimal particle agglomeration during the deposition and activation steps. Structural data obtained from the physical characterization of the Au catalysts were comparable to features exhibited from a traditionally prepared standard Au catalyst obtained from the World Gold Council (WGC). A differential kinetic study of CO oxidation catalysis by the …

Kinetic Analysis Of Oleic Acid Esterification Using Lipolytic Enzyme As Catalyst, Mohd S. Mahmud, James W. Ryan, Cyrus Cooper, Tomasz Safinski, Mark I. Nelson, Harvinder S. Sidhu, Soji A. Adesina

Faculty of Informatics - Papers (Archive)

This paper deals with the esterification kinetics of oleic acid (OA) using ethanol (EtOH) over acrylic-supported lipase from Aspergillus niger (Novozym 435) as catalyst. The reaction was carried out in a stirred 500 mL Pyrex glass reactor at 45oC under conditions with negligible external and internal transport resistances. Reaction runs in a microaqueous medium employed OA: EtOH ratio, b, between 0.01 to 2.0 without initial addition of water. The rate dependency on reactant concentration has a maximum at b=0.9, just below the stoichiometric ratio, and was therefore described by a Michaelis- Menten kinetic expression implicating irreversible surface reaction between adsorbed …