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Computational Modeling Of The Structure And Catalytic Behavior Of Graphene-Supported Pt And Ptru Nanoparticles, Raymond Gasper Oct 2018

Computational Modeling Of The Structure And Catalytic Behavior Of Graphene-Supported Pt And Ptru Nanoparticles, Raymond Gasper

Doctoral Dissertations

Computer modeling has the potential to revolutionize the search for new catalysts for specific applications primarily via high-throughput methodologies that allow researchers to scan through thousands or millions of potential catalysts in search of an optimal candidate. To date, the bulk of the literature on computational studies of heterogeneous catalysis has focused on idealized systems with near-perfect crystalline surfaces that are representative of macroscopic catalysts. Advancing the frontier to nanoscale catalysis, in particular, heterogeneous catalysis on nanoclusters, requires consideration of low-symmetry nanoparticles with realistic structures including the attendant complexity arising from under-coordination of catalyst atoms and dynamic fluxionality of clusters. …


First-Principles Study On The Catalytic Role Of Cerium Dioxide In The Conversion Of Organic Compounds, Chuanlin Zhao Oct 2018

First-Principles Study On The Catalytic Role Of Cerium Dioxide In The Conversion Of Organic Compounds, Chuanlin Zhao

LSU Doctoral Dissertations

Ceria is an earth-abundant material that has been widely used in heterogeneous catalysis, environmental catalysis, and energy applications thanks for its ability to readily convert between different oxidation states. The objective of this study is to theoretically elucidate the reaction mechanisms for the conversion of model organic compounds on ceria, in order to gain insights for the design of cost-effective and selective ceria-based catalysts. Acetaldehyde, acetic acid, and para-nitrophenyl phosphate monoester were selected as the model compounds to probe ceria surfaces. Density functional theory calculations can provide accurate predictions of adsorption and reaction energetics, which can be used to …


Electronic Effect Of Platinum Alloy Catalysts On Olefin Hydrogenation Kinetics, Colin Reedy, Jeff Miller, Stephen Purdy Aug 2018

Electronic Effect Of Platinum Alloy Catalysts On Olefin Hydrogenation Kinetics, Colin Reedy, Jeff Miller, Stephen Purdy

The Summer Undergraduate Research Fellowship (SURF) Symposium

Dehydrogenation of alkanes is the first step in transforming light hydrocarbons into liquid fuels and chemicals. This process has traditionally used platinum alloys as catalysts. Alloys are used industrially because they have a greater selectivity than monometallic platinum. Alloying platinum with an inactive promoter modifies the crystalline structure of the surface (geometric effect), and the 5d electrons in platinum responsible for chemistry (electronic effect); both have been suggested to be primarily responsible for dehydrogenation selectivity in platinum alloys. Alloy catalysts have been synthesized using early 3d transition metal promoters with the same Pt3M crystal structure. X-Ray Absorption Spectroscopy …


Investigation Of The Effects Of Solid-State Treatments On The Structure And Mobility Of Copper In Zeolites, Jiayang Wu, Laura Wilcox, Rajamani Gounder Aug 2018

Investigation Of The Effects Of Solid-State Treatments On The Structure And Mobility Of Copper In Zeolites, Jiayang Wu, Laura Wilcox, Rajamani Gounder

The Summer Undergraduate Research Fellowship (SURF) Symposium

Zeolites are microporous, aluminosilicate catalysts that play an important role in industrial applications as well as studies for the fundamental understanding of catalysts for emerging reactions of interest. The introduction of aluminum into the zeolite lattice introduces a negative charge on the framework that can be balanced with extra-framework cations. The control of the aluminum distribution and the choice of charge balancing cations allows for the ability to tailor the active sites to facilitate a desired reaction. This research focuses on studying copper active sites in zeolites. Copper oxide was used as a copper precursor to introduce copper ions in …


Microwave-Assisted Synthesis Of Palladium Nanoparticles Supported On Copper Oxide In Aqueous Medium As An Efficient Catalyst For Suzuki Cross-Coupling Reaction, Hany A. Elazab, M. A. Sadek, Tamer T. El-Idreesy Jul 2018

Microwave-Assisted Synthesis Of Palladium Nanoparticles Supported On Copper Oxide In Aqueous Medium As An Efficient Catalyst For Suzuki Cross-Coupling Reaction, Hany A. Elazab, M. A. Sadek, Tamer T. El-Idreesy

Chemical and Biochemical Engineering Faculty Research & Creative Works

We report here a reliable green method for the synthesis of palladium nanoparticles supported on copper oxide as a highly active and efficient catalyst for Suzuki cross-coupling reaction. The experimental synthetic approach is based on microwave-assisted chemical reduction of an aqueous mixture of palladium and copper salt simultaneously using hydrazine hydrate as reducing agent. The catalyst was fully characterized using various techniques showing well-dispersed palladium nanoparticles. The catalytic activity and recyclability of the prepared catalyst were experimentally explored in the ligand-free Suzuki cross-coupling reaction with a diverse series of functionalized substrates. The synthesized Pd/CuO catalyst shows many advantages beside its …


The Catalytic Activity Of Copper Oxide Nanoparticles Towards Carbon Monoxide Oxidation Catalysis: Microwave – Assisted Synthesis Approach, Hany A. Elazab Jun 2018

The Catalytic Activity Of Copper Oxide Nanoparticles Towards Carbon Monoxide Oxidation Catalysis: Microwave – Assisted Synthesis Approach, Hany A. Elazab

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this research, we report a simple, versatile, and reproducible method for the synthesis of copper oxide nanoparticles via microwave assisted synthesis approach. The important advantage of this catalyst is due to its important role not only in the low temperature oxidation of CO but also in potential applications in pharmaceutical and fine chemical synthesis. The results reveal that the copper oxide catalyst has particularly a remarkable high activity for CO oxidation catalysis as it was found that copper oxide (CuO) catalyst has 100% conversion of carbon monoxide into carbon dioxide at 175 oC. This also could be attributed to …


Spectro-Electrochemical Platforms For Dynamic Analyses Of Catalytic Cascade Systems, Nalin I. Andersen Apr 2018

Spectro-Electrochemical Platforms For Dynamic Analyses Of Catalytic Cascade Systems, Nalin I. Andersen

Nanoscience and Microsystems ETDs

The development of spectro-electrochemical platforms that facilitate the dynamic analyses of complex catalytic cascade systems was explored in this research. These systems facilitated multiple modalities of catalysts and were used as platforms for monitoring catalytic transformations quasi-in situ. The analytical platforms allowed for the characterization of intermediates and products using surface-enhanced Raman spectroscopy (SERS). The design and fabrication of these devices proved to be reproducible, made of materials that can be manipulated for multiple applications, and incorporate fluid mechanics, electrochemistry, and multimodal catalysis. Microfluidic technology offers capabilities for understanding catalytic cascade systems by providing precise dynamic control of …


Microwave-Assisted Synthesis Of Palladium Nanoparticles Supported On Copper Oxide In Aqueous Medium As An Efficient Catalyst For Suzuki Cross-Coupling Reaction, Hany A. Elazab, M. A. Sadek, Tamer T. El-Idreesy Mar 2018

Microwave-Assisted Synthesis Of Palladium Nanoparticles Supported On Copper Oxide In Aqueous Medium As An Efficient Catalyst For Suzuki Cross-Coupling Reaction, Hany A. Elazab, M. A. Sadek, Tamer T. El-Idreesy

Chemical Engineering

We report here a reliable green method for the synthesis of palladium nanoparticles supported on copper oxide as a highly active and efficient catalyst for Suzuki cross-coupling reaction. The experimental synthetic approach is based on microwave-assisted chemical reduction of an aqueous mixture of palladium and copper salt simultaneously using hydrazine hydrate as reducing agent. The catalyst was fully characterized using various techniques showing well-dispersed palladium nanoparticles. The catalytic activity and recyclability of the prepared catalyst were experimentally explored in the ligand-free Suzuki cross-coupling reaction with a diverse series of functionalized substrates. The synthesized Pd/CuO catalyst shows many advantages beside its …


Laboratory Catalytic Reactors For Testing Heterogeneous Catalysts: A Practical Introduction, Steven Zhou, Jason Yang Jan 2018

Laboratory Catalytic Reactors For Testing Heterogeneous Catalysts: A Practical Introduction, Steven Zhou, Jason Yang

Jason Yang

Laboratory catalytic reactors are commonly used to evaluate performance of heterogeneous catalysts. It is of importance to select appropriate reactors for specific catalytic system before actual experiments are carried out. In the present work, various laboratory catalytic reactors are introduced and summarized for testing heterogeneous catalysts.


Assembling Of Niox/Mwcnts-Gc Anodic Nanocatalyst For Water Electrolysis Applications, Islam M. Al-Akraa Dr., Yaser M. Asal Mr, Saher D. Khamis Eng Jan 2018

Assembling Of Niox/Mwcnts-Gc Anodic Nanocatalyst For Water Electrolysis Applications, Islam M. Al-Akraa Dr., Yaser M. Asal Mr, Saher D. Khamis Eng

Chemical Engineering

Glassy carbon (GC) electrode is intended to be modified with nickel oxide (NiOx) and multiwalled carbon nanotubes (MWCNTs) in the anodic reaction of water electrolysis. NiOx deposition time is optimized and a 5 min was enough to attain the maximum activity. A further modification of the catalyst with MWCNTs could greatly enhance its stability during continuous electrolysis. As an outcome, an energy amount of 21.7 kWh/KgO2 is minimized. Several electrochemical and materials characterization setups will be utilized to test the catalyst activity and to know its geometry and structure.


Atomic Layer Deposition Prepared Nanostructured Materials For Various Catalytic Reactions, Xiaofeng Wang Jan 2018

Atomic Layer Deposition Prepared Nanostructured Materials For Various Catalytic Reactions, Xiaofeng Wang

Doctoral Dissertations

"Atomic layer deposition (ALD) has been widely used for thin film coating and metal nanoparticles (NPs) preparation. In this report, the applications of ALD prepared nanostructured materials in catalysis were examined.

Highly dispersed Pt monometallic catalysts with different substrates and multi-walled carbon nanotubes (MWCNTs) supported Pt-Co bimetallic catalysts were synthesized by ALD for selective hydrogenation of α, β-unsaturated aldehydes to unsaturated alcohols (UA). Pt/MWCNTs showed the highest selectivity of UA in selective hydrogenation of citral, as compared to Pt/SiO2, Pt/ALD-Al2O3, and Pt/γ-Al2O3. After adding Co, the highest selectivity was achieved …


Engineering Zeolite Catalysts Through Porosity And Surface Acidity Control For Selective Production Of Light Olefins, Xin Li Jan 2018

Engineering Zeolite Catalysts Through Porosity And Surface Acidity Control For Selective Production Of Light Olefins, Xin Li

Doctoral Dissertations

"Zeolites are broadly used as heterogeneous catalysts in various chemical and petrochemical industries to produce value-added chemicals and fuels, mainly due to their large surface area, acid-base properties, high thermal stability, and excellent shape-selectivity. In this dissertation, various zeolite catalysts were engineered through fine-tuning micro-meso-macro-porosity and surface acidity. The engineered zeolites were used as heterogeneous catalysts for production of light olefins such as ethylene and propylene through alcohol dehydration and hydrocarbon cracking reactions.

To control the zeolite porosity and acidity, SAPO-34@ZSM-5 and SAPO-34@Silicalite-1 composites with core-shell structure were synthesized and evaluated in ethanol dehydration reaction. Analysis of catalytic performance revealed …