Engineering Commons^™

Sn-Doped Α-Fe2O3 Photocatalyst Containing Oxygen Vacancy For Water-Splitting, Zu-Hua Wang, Dong-Fang Niu, Hui-Cheng Li, Rong-Bin Du, Heng Xu, Xin-Sheng Zhang

Journal of Electrochemistry

The α-Fe₂O₃ nanoparticles containing oxygen vacancies were synthesized in atmospheric N₂ by dip-dropping method without a high vacuum employed before annealing. The influences of annealing atmosphere and Sn-doping on the photocatalytic performance of α-Fe₂O₃ nanoparticles were studied by annealing the photocatalyst in N₂ or air and adding SnCl₄ to the precursor directly. The results showed that the current density of Sn-doping α-Fe₂O₃ annealed in N₂ at 550 °C and 1.23 V (vs. RHE) was 35 times greater than that of pristine α-Fe_{2 …}

Electrochemical Synthesis Of Porous Polyaniline Electrodes Using Hkust-1 As A Template And Their Electrochemical Supercapacitor Property, Qiong Luan, Chun-Feng Xue, Hong-Ye Zhu, Fu-Juan Yang, Xu-Li Ma, Xiao-Gang Hao

Journal of Electrochemistry

Excellent electrode plays vital important role in the performance of supercapacitors. Polyaniline (PANI) with good conductivity is often used to prepare electrode. However, its available surface is limited and results in a poor supercapacitance in many cases. It is desirable to fabricate an electrode containing electroactive PANI with high surface area deriving from its porous structure. Here, the metal-organic framework (MOF) material with high surface area was selected as a hard template for synthesizing porous PANI. Microporous PANI composite electrodes (Micro-PANI/CC) were fabricated by depositing aniline on to carbon cloth (CC) pre-coated with MOF material of HKUST-1 using a unipolar …

Direct Electrochemistry Of Glucose Oxidase Based On Ws2 Quantum Dots And Its Biosensing Application, Chen-Lu Li, Hua-Ping Peng, Zhong-Nan Huang, Yi-Lun Sheng, Pei-Wen Wu, Xin-Hua Lin

Journal of Electrochemistry

In this study, a novel electrochemical glucose biosensor has been developed by immobilizing glucose oxidase (GOx) on tungsten disulfide quantum dots (WS₂ QDs) on the surface of glassy carbon electrode (GCE). Transmission electron microscopy, UV-vis spectroscopy and cyclic voltammetry were employed to characterize the morphology, structure, and electrochemical behaviors of the as-prepared WS₂ QDs and the biofilm modified electrode. The results suggested that the WS₂ QDs could accelerate the electron transfer between the electrode and the immobilized enzyme, which enabled the direct electrochemistry of GOx without any electron mediator. Besides, the immobilized GOx in WS₂ QDsfilm …

The Problem Of The Anode Electrolyte In H-Type Electrolytic Cell For Electrochemical Reduction Of Carbon Dioxide, Rui Zhang, Wei-Xin Lv, Li-Xu Lei

Journal of Electrochemistry

Electrochemical reduction of carbon dioxide (CO₂) was studied in the H-type electrolytic cell. It was found that the voltage between the cathode and the anode would increase during the long time electrolysis process, for this reason the electrolytic process would be unsustainable. After the experimental investigations carried out by constant potential electrolysis, constant current electrolysis, pH test and KHCO₃ concentration analysis of anode electrolyte before and after the electrolysis, the increase in cell voltage might be caused by the following process: H⁺, that was generated from the anodic oxygen evolution reaction, reacted with HCO_{3 …}

Application Of Adamantane Schiff Base Nickel Complexes/Graphene Oxide/Glassy Carbon Modified Electrode In Detection Of Carmine, Peng Guo, Zheng Liu, Hai-Ying Li, Li-Ming Ma

Journal of Electrochemistry

The Schiff base nickel complexes/graphene oxide/glassy carbon electrodes were prepared by embedded method and electrodeposition on which were used to quantitatively detect the contents of carmine. Cyclic voltammetry, chronoamperometry, scanning electron microscopy (SEM) and other methods were employed to characterize properties and morphologies of the modified electrodes. The results show that the adamantane double Schiff base nickel complexes/graphene oxide/glassy carbon electrode had high electric catalytic activity toward carmine oxidation reaction, and might provide an easy and quick way to detect carmine content with good reproducibility.

A New Thin Layered Structural Coating On A Metal Substrate For Enhanced Hydrogen Production From Steam Methane Reforming, Michael A. Lugo-Pimentel

Dissertations and Theses

In the past decade the use of hydrogen has become more ubiquitous. Its applications range from the upgrading of fossil fuels, to the production of ammonia, to the hydrogenation of fats, to the production of muriatic acid and methanol, all without including the efforts being taken to move towards a hydrogen economy. Its widespread use and its increasing demand lays pressure to find more efficient techniques of hydrogen production. Because the overwhelming majority of hydrogen produced nowadays comes from the steam reforming of natural gas (SMR), it appears that the most adept way to improve yields is by improving the …

Improving Performance Of Au/Ts-1 Catalyst For Propylene Epoxidation, Jacob Kunisch, Zheng Lu

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

C.V. - Wojciech Budzianowski, Wojciech M. Budzianowski

Wojciech Budzianowski

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Renewable Energy And Sustainable Development (Resd) Group, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.

Synthesis Of Copper Oxide Nanoparticles In Droplet Flow Reactors, Christopher Reilly

Honors Theses and Capstones

Synthesis of metal oxide nanoparticles within droplet flow reactors is advantageous over batch synthesis due to the elimination of concentration and temperature gradients inside the reactor and prevention of reactor fouling. We present results on the synthesis of copper oxide nanoparticles using aqueous droplets of copper acetate and acetic acid inside a bulk stream of sodium hydroxide in 1-octanol. Varying the copper acetate, acetic acid, and sodium hydroxide concentration resulted in needle-like and plate-like nanoparticles of varying sizes. The rate of mass transfer from the bulk to the droplet phase was found to increase with flow rate and addition of …

Photocatalytic Decomposition Of Phenol Under Visible And Uv Light Utilizing Titanium Dioxide Based Catalysts, Marjorie G. Steiner

Honors Theses and Capstones

Pollution in wastewater effluvia from phenol and phenolic compounds is a common occurrence in many industrial manufacturing plants. Phenol is toxic to human beings as well as a contaminant to the environment, meanwhile, it is difficult to remove from wastewater due to its non-biodegradable nature. To boost the rate of decomposition, various catalytic approaches have been developed. With the interest of decreasing operation cost, titanium dioxide (TiO₂) based catalysts have emerged as good candidates for the photocatalytic process.

In this honors project, a series of TiO₂ based catalysts, including TiO₂, N-TiO₂, Cu-TiO_{2 …}

Use Of Natural Ores As Oxygen Carriers In Chemical Looping Combustion: A Review, Michael J. Matzen, Jessica Pinkerton, Xiaomeng Wang, Yaşar Demirel

Department of Chemical and Biomolecular Engineering: Faculty Publications

Chemical looping combustion (CLC) has gained considerable ground in energy production due to its inherent carbon capture with a minimal energy penalty. The choice of metal oxide used as an oxygen carrier (OC) in CLC has a substantial weight on the overall efficiency of energy production as well as the ultimate cost per MW. While much work has gone into manufacturing synthetic OCs with high fuel conversions, harsh operating conditions and process limitations cause some unavoidable loss of the oxygen carrier. With low production costs and minimal conditioning required, natural ores have grown in interest as cheap alternative oxygen carriers. …

Synthesis And Energy Applications Of Mesoporous Titania Thin Films, Syed Z. Islam

Theses and Dissertations--Chemical and Materials Engineering

The optical and electronic properties of TiO₂ thin films provide tremendous opportunities in several applications including photocatalysis, photovoltaics and photoconductors for energy production. Despite many attractive features of TiO₂, critical challenges include the innate inability of TiO₂ to absorb visible light and the fast recombination of photoexcited charge carriers. In this study, mesoporous TiO₂ thin films are modified by doping using hydrogen and nitrogen, and sensitization using graphene quantum dot sensitization.

For all of these modifiers, well-ordered mesoporous titania films were synthesized by surfactant templated sol-gel process. Two methods: hydrazine and plasma treatments have been …

Tunable Nanocomposite Membranes For Water Remediation And Separations, Sebastián Hernández Sierra

Theses and Dissertations--Chemical and Materials Engineering

Nano-structured material fabrication using functionalized membranes with polyelectrolytes is a promising research field for water pollution, catalytic and mining applications. These responsive polymers react to external stimuli like temperature, pH, radiation, ionic strength or chemical composition. Such nanomaterials provide novel hybrid properties and can also be self-supported in addition to the membranes.

Polyelectrolytes (as hydrogels) have pH responsiveness. The hydrogel moieties gain or lose protons based on the pH, displaying swelling properties. These responsive materials can be exploited to synthesize metal nanoparticles in situ using their functional groups, or to immobilize other polyelectrolytes and biomolecules. Due to their properties, these …

Fractionation And Characterization Of Lignin Streams From Genetically Engineered Switchgrass, Enshi Liu

Theses and Dissertations--Biosystems and Agricultural Engineering

Development of biomass feedstocks with desirable traits for cost-effective conversion is one of the main focus areas in biofuels research. As suggested by techno-economic analyses, the success of a lignocellulose-based biorefinery largely relies on the utilization of lignin to generate value-added products, i.e. fuels and chemicals. The fate of lignin and its structural/compositional changes during pretreatment have received increasing attention; however, the effect of genetic modification on the fractionation, depolymerization and catalytic upgrading of lignin from genetically engineered plants is not well understood. This study aims to fractionate and characterize the lignin streams from a wild-type and two genetically engineered …

Investigating A Sequentially Assembled Mnox/Pt Nanocatalyst As A Potential Anode For Ethylene Glycol Fuel Cells, Ghada El-Nowihy

Chemical Engineering

Aiming at a better electrocatalytic enhancement of ethylene glycol (EG) electrooxidation (EGO) in an alkaline medium for EG fuel cells (EGFCs), a MnOx/Pt anode was developed. A sequential layer-by-layer electrodeposition technique was employed to assemble first platinum nanoparticles (nano-Pt) directly onto the surface of a glassy carbon (GC) electrode then manganese oxide nanoparticles (nano-MnOx) were next immobilized. Field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectroscopy (EDS) were employed to evaluate the surface morphology and the bulk composition of the proposed catalyst in addition to the relative ratio of the catalyst’s ingredients. On the other hand, the catalyst …

Optimising The Performance Of Cement-Based Batteries, Aimee Byrne, Shane Barry, Niall Holmes Dr., Brian Norton

Articles

The development of a battery using different cement-based electrolytes to provide a low but potentially sustainable source of electricity is described. The current, voltage, and lifespan of batteries produced using different electrolyte additives, copper plate cathodes, and (usually) aluminium plate anodes were compared to identify the optimum design, components, and proportions to increase power output and longevity. Parameters examined include water/cement ratio, anode to cathode surface area ratio, electrode material, electrode spacing, and the effect of sand, aggregate, salts, carbon black, silica fume, and sodium silicate on the electrolyte. The results indicate that the greatest and longest lasting power can …

Pore-Confined Carriers And Biomolecules In Mesoporous Silica For Biomimetic Separation And Targeting, Shanshan Zhou

Theses and Dissertations--Chemical and Materials Engineering

Selectively permeable biological membranes composed of lipophilic barriers inspire the design of biomimetic carrier-mediated membranes for aqueous solute separation. This work imparts selective permeability to lipid-filled pores of silica thin film composite membranes using carrier molecules that reside in the lipophilic self-assemblies. The lipids confined inside the pores of silica are proven to be a more effective barrier than bilayers formed on the porous surface through vesicle fusion, which is critical for quantifying the function of an immobilized carrier. The ability of a lipophilic carrier embedded in the lipid bilayer to reversibly bind the target solute and transport it through …

Platinum Nanoparticles-Cobalt Oxide Nanostructures As Efficient Binary Catalyst For Ethylene Glycol Electro-Oxidation, Ghada El-Nowihy

Chemical Engineering

An enhanced electrocatalytic activity towards ethylene glycol oxidation reaction (EGO) in alkaline medium is observed at a glassy carbon (GC) electrode modified with a nanoparticle-based binary catalyst composed of Pt (nano-Pt) and cobalt oxide (nano-CoOx). The electrocatalytic activity of the modified electrodes towards EGO depends on the loading level as well as the composition of the catalyst layer atop the GC electrode surface. Several techniques including cyclic voltammetry (CV), field-emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectroscopy (EDS) are used to address the catalytic activity of the proposed catalyst and to reveal their surface morphology and composition, respectively. …

Platinum-Rhodium Alloy Electrocatalyst Activities In The Methanol Oxidation Reaction, William R. Sandorf

Williams Honors College, Honors Research Projects

This study evaluates the electrochemical activity of several compositions of platinum-rhodium alloys on carbon support to identify potential replacements for the expensive platinum electrocatalysts currently used in direct methanol fuel cells (DMFCs). The electrochemical active surface areas (ECSAs) of each sample were determined using cyclic voltammetry (CV) in a 0.5 M H₂SO₄ solution to normalize CV currents generated in the methanol oxidation reaction (MOR). The activity of five compositions was tested; Pt₃Rh, Pt₂Rh, PtRh, Pt₂Rh, and Pt₃Rh. 100 mg of each catalyst was synthesized at 10% by weight platinum …

Catalytic Hydrotreatment For The Development Of Renewable Transportation Fuels, Lilu Funkenbusch

Dissertations, Master's Theses and Master's Reports

Biologically-derived feedstocks are a highly desirable source of renewable transportation fuel. They can be grown renewably and can produce fuels similar in composition to conventional fossil fuels. They are also versatile and wide-ranging. Plant oils can produce renewable diesel and wood-based pyrolysis oils can be made into renewable gasoline. Catalytic hydrotreatment can be used to reduce the oxygen content of the oils and increase their viability as a “drop-in” transportation fuel, since they can then easily be blended with existing petroleum-based fuels. However, product distribution depends strongly on feedstock composition and processing parameters, especially temperature and type of catalyst. Current …

Biomimetic Devices To Drive A Thermodynamically Uphill Reaction Using Light And To Degrade Industrial Waste Stream Components, Madison Joanne Sloan

Theses and Dissertations--Chemistry

Given the amount of industrial waste produced each year, as well as the accruing amount of greenhouse gases in our atmosphere produced by the burning of fossil fuels, it is imperative that humanity develop environmentally-sustainable sources of energy and methods of remediation. Nature achieves both of these by use of enzymes as catalysts, inspiring interest in designing biomimetic systems capable of harnessing clean energy and remediating industrial waste. This study examined the ability of enzymes in electrochemical and convective flow systems to achieve these tasks. The first portion studied the incorporation of enzymes into an electrochemical system to drive the …

Preparation And Application Of Catalysts For The Stereospecific Reduction And Photooxygenation Of Olefins In Continuous Operations: A Novel Method For The Production Of Artemisinin, Daniel C. Fisher

Theses and Dissertations

Over the last two centuries, the discovery and application of catalysts has had a substantial impact on how and what chemicals are produced.Given their broad significance, our group has focused on developing new catalyst systems that are recoverable and reusable, in an attempt to reduce concomitant costs.

Our efforts have centered on constructing a recyclable chiral heterogeneous catalyst capable of effecting asymmetric hydrogenations of olefins with high stereoselectivity. A class of phosphinoimidazoline ligands, developed by researchers at Boehringer-Ingelheim, known as BIPI ligands, have proven efficacious in the asymmetric reduction of alkenes. However, these chiral ligands are homogeneous and coordinated to …