Materials Chemistry Commons^™

Fe/Co/Ni-Doped Mos2 An Electrocatalyst For Overall Water Splitting, Himanshi Lnu

Electronic Theses & Dissertations

Electrochemical water splitting is a promising method for sustainable hydrogen production, addressing global energy challenges. However, its practical application is limited by the need for efficient and durable electrocatalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). In this study, MoS₂ was doped with Co, Ni, and Fe at varying concentrations (5:0.5, 5:1, and 5:1.5) using a hydrothermal synthesis method to evaluate their potential as electrocatalysts for water splitting. Characterization revealed that metal doping significantly altered the electronic and morphological properties of MoS₂, enhancing its catalytic performance. Electrochemical evaluations in alkaline media demonstrated that Co-doped MoS₂ …

Trade-Off Between Limonene & Geraniol-Based Reprocessable And Non-Reprocessable Epoxy Thermosets: Role Of Aliphatic Diamines In Polymer Networks Design, Priyankkumar Kanubhai Patel

Electronic Theses & Dissertations

The growing demand for sustainable materials, driven by environmental concerns and the rapid depletion of fossil fuels, has garnered significant attention in the fabrication of bio-based epoxy thermosets as renewable alternatives to petroleum-derived thermosetting polymers. The present study focuses on the synthesis and characterization of epoxy prepolymer resins derived from limonene and geraniol via a two-step process, followed by the fabrication of thermally cross-linked flexible epoxy thermoset films using various traditional aliphatic diamine curing agents, namely 1,2-ethylenediamine (EDA), 1,4-butylenediamine (BDA), and 1,6-hexamethylenediamine (HDA). Additionally, the incorporation of cystamine, a disulfide-containing diamine, enabled the formation of a covalent adaptable network through …

Optimization Of Transition-Metal Inclusive Carbon Aerogels For Electrochemical Energy Applications, Allen Dalton Davis

Electronic Theses & Dissertations

The ever-growing need for energy alongside rising concerns for climate change demands the development of renewable energy technologies. Hydrogen fuel cells are a promising technology that can serve to either supplement energy generation or act as a lone power source. Yet for these devices to be truly green, the hydrogen that serves as fuel must be procured from a renewable resource. Electrolytic water splitting is a process that allows for the dissociation of water into H₂ and O₂. For this process to be practical, the electrolyzer needs to demonstrate high efficiency and stability, as well as a …

Exploring Soybean Oil-Based Polyol And Effect Of Non-Halogenated Flame Retardants In Rigid Polyurethane Foam, Sahithi Kondaveeti

Electronic Theses & Dissertations

To address the increasing demand for sustainable biomaterials due to the depletion of fossil fuel resources and growing environmental concerns, a new type of biodegradable and environmentally friendly rigid polyurethane foam (RPUF) has been synthesized. These foams are derived from chemically modified soybean oil-based polyol obtained from soybean oil by epoxidation followed by a ring-opening reaction. Polyurethane foam is generally used in construction, furniture, and automobile industries but is highly flammable and releases toxic gases and smoke during combustion. In this study, a highly efficient synergistic effect halogen-free flame-retardant (FR) melamine salt, 2-carboxyethyl(phenyl)phosphinic acid melamine salt (CMA) was synthesized from …

Enhanced Mechanical Strength Of Soybean Oil-Based Non-Isocyanate Polyurethane Adhesive For Wood Application By Introducing Nanofillers, Vatsal Chaudhari

Electronic Theses & Dissertations

Polyurethane (PU) is a versatile material that finds extensive use in various industries including bedding, construction, automotive, and packaging. Historically, this particular polymer relied significantly on petrochemical resources, a practice that was considered to have negative environmental impacts. The conventional method for preparing PU involves the use of isocyanate, which is a disadvantage due to its negative impact on the environment and human health. The resolution of this problem entails identifying an appropriate substitute for petroleum-derived products that minimize their impact on both the environment and human health. The researchers earlier utilized soybean oil, for the formulation of PUs in …

Castor Oil Polyol-Based Adhesives With Additional Crosslinker For Improvement In Mechanical And Thermal Properties., Yash Desai

Electronic Theses & Dissertations

Polyurethanes (PU) have been promising polymeric materials with many applications, including adhesives. Projecting an estimated revenue from 42.8 billion $ in 2021 to 61.5 billion $ by 2026. However, a large number of PU adhesives are sourced from petroleum products. Therefore, to lower the dependence on non-renewable resources and provide sustainable and affordable alternatives. In this work will synthesize bio-based adhesives of polyurethane from modified castor oil-based polyol. Generally, polyurethane reaction depends on the properties of polyol and isocyanates. The most important aspect of these reactions is the OH number of the polyol, which is responsible for the crosslinking and …

Evaluation Of Promising Eco-Friendly Flame Retardants For Bio-Based Rigid Polyurethane Foams Based On Modified Castor Oil, Prasadi Abeysinghe Arachchilage

Electronic Theses & Dissertations

Fossil fuel derivatives in the polyurethane industry are gradually being replaced with environmentally friendly alternative bio-based resources. Vegetable-oil-based polyols are emerging bio-based resources that can decrease cost competitiveness in polyurethane markets, reduce environmental impacts, and meet the urgent need for green and sustainable development strategies. Among this, interest is the use of castor oil to make polyurethane because of its inedibility and the fact that it contains many functionalizable chemical groups. However, the poor thermal stability and low load-bearing capacity of castor-oil-based rigid polyurethane foam limits its application. Two methods were used to address these limitations: (i) more hydroxyl groups …

Electrochemical Properties Of Mof-Derived Nickel Compounds For High-Performance Supercapacitors And Electrocatalysts, Shiva Bhardwaj

Electronic Theses & Dissertations

There are various forms in which humans use energy in daily life. From applications that require a high energy density to long-term storage, the requirements for energy usage are diverse. Therefore, with the continuous increase in users worldwide, more practical energy-driven sources are required, allowing manufacturers to look toward emerging functional materials. An emerging class of functional porous materials referred to as metal-organic framework (MOF) has received considerable attention over the past two decades, partially because of their potential use in various applications, including gas storage, molecular separations, electrocatalyst, and energy devices. For example, metal oxide and hydroxide-based MOF materials …

Transistion Metal Chalcogenides And Phosphides For Energy Storage And Conversion Through Water Splitting, Kelsey Thompson

Electronic Theses & Dissertations

In contemporary society, there are many different ways that energy is used in daily life. From applications that require a high energy density to long-term storage in a stable manner, the requirements for energy usage are diverse. Therefore, the greater the number of uses a designed material exhibits, the more practical it may be for wide-scale manufacture. Two areas of particular interest for energy applications are fuel cells (to generate energy) and supercapacitors (to store energy). To provide cheaper and more durable alternatives for energy storage, electrodes containing CoMoO₄, NiMoO₄, CoMoS₄, NiMoS₄, …

One-Step Synthesis Of Corn Oil-Based Polyol For Highly Flame-Retardant Rigid Polyurethane Foams, Tenzin Ingsel

Electronic Theses & Dissertations

Rigid polyurethane foams (RPUF), heavily utilized in construction, refrigeration, and the automotive industries, are a significant class of polyurethanes. They can substantially enhance energy efficiency by improving thermal insulation. However, the application of petrochemical sources in polyurethane has raised environmental concerns.

Such concerns call for the development and application of new bio-based polyurethanes to potentially reduce humanity's over-reliance on nonrenewable sources.

In this work, corn oil-based polyol was synthesized via popularized thiol-ene reaction. The obtained polyol was characterized by wet chemistry methods, spectroscopic evaluations, and chromatography. Non-halogenated flame retardants of cost-effective and environmentally friendly nature were incorporated into the polyurethane …

Multifunctional Carbon-Supported Cobalt-Nickel Compounds For Water Splitting And Energy Storage Applications, Wang Lin

Electronic Theses & Dissertations

In order to effectively reduce carbon emission and achieve the goal of mitigating climate change, hydrogen energy has high hopes as a representative of green energy. According to the most current and updated research, compounds of cobalt and nickel have been widely studied as alternatives instead noble metal materials as catalysts for the electrolysis of water. Based on some other research reports, a hydrothermal method to grow cobalt-nickel hydroxide on nickel foam that has been carbonized in advance was proposed. To compare the modification results of these materials by different activation methods, calcination, sulfidation, and phosphating were performed on the …

Facile Synthesis Of Metal Oxides, Sulphides, And Phosphides For Enhanced Energy Applications, Alfred Nkhama

Electronic Theses & Dissertations

An access to reliable, sustainable, eco-friendly and cost-effective energy supply is being challenged by the global increase in population and the rapid technological advancement. Sophisticated systems, machinery and various devices being innovated, require the steady energy supply for their operations and applicability. To have reliable energy, numerous researches are being conducted through various approaches across the world. In this research work, the facile approach in investigating and tuning the materials properties was employed to improve energy properties of metal oxides. Nanostructured NiFe-oxide and CoFe-oxide were synthesized using a facile coprecipitation method. It was revealed that; nanostructured materials have favorable structures …

Effect Of Post-Consumer Content And Bioplastic Incorporation On Polymeric Resin In Consumer Applications, Shelby Bicknell

Electronic Theses & Dissertations

Controversy surrounds the use of plastic products, primarily due to their potentially negative impact on the environment at the end of their lifecycle. The most widely used plastics are manufactured from petrochemicals such as petroleum, coal or natural gas. Petrochemical plastics are not able to readily breakdown in the environment, which aggravates the existing pollution problems. Fortunately, there are eco-friendly alternatives to petrochemical-based plastics. Bioplastics may be derived from renewable sources, biodegradable, or both. Bio-based plastics are plastics that may be derived from renewable biomass sources including, but not limited to, vegetable oils, cornstarch, straw, woodchips, and food waste. They …

Method Development To Quantify The Reinforcing Properties Of Silica Fillers, Hamid Reza Givehchi

Electronic Theses & Dissertations

Polysiloxane polymers are widely used as a high-temperature resistant materials with the ability to maintain flexibility at extremely low temperatures. Unfortunately, polysiloxane elastomers generally exhibit low strength and poor mechanical properties and have no practical use unless they are reinforced. These elastomers can be mechanically improved through the use of reinforcing silica-based fillers. It is known that silanol groups on the surface of silica filler particles can interact with the polysiloxane backbone. Interactions of silanol groups on the fillers’ surfaces with the polysiloxane backbone through hydrogen bonding may hinder the mobility of the polymer chain and can improve thermal, physical, …

Nanocomposites Of Polypyrrole And Cobalt Oxide As Efficient And Stable Multifunctional Materials For Supercapacitors And Overall Water Splitting, Ahlam Alghamdi

Electronic Theses & Dissertations

NANOCOMPOSITES OF POLYPYRROLE AND COBALT OXIDE AS EFFICIENT AND STABLE MULTIFUNCTIONAL MATERIALS FOR SUPERCAPACITORS AND OVERALL WATER SPLITTING

An Abstract of the Thesis by

Ahlam Alghamdi

The main objective of this study is to synthesize nanostructured cobalt oxide decorated on polypyrrole using a facile method for energy applications. For this, polypyrrole was first synthesized using a chemical polymerization method. In the second step, a varying amount of cobalt oxide was decorated on polypyrrole using a hydrothermal process. The synthesized materials were structurally and electrochemically characterized. It was observed that the electrochemical properties of the composites depend on their composition. The …

Highly Flame Retardant And Bio-Based Rigid Polyurethane Foams Derived From Orange Peel Oil, Chunyang Zhang

Electronic Theses & Dissertations

Polyurethane is an important class of polymer which is being used for various industrial applications in the form of rigid foams, flexible foams, thermoplastic, elastomer, coating, and adhesive. Especially there is a huge market for rigid polyurethane foams for their applications as thermal insulating material in building and housing. In general, polyurethanes are prepared using polyols and diisocyanates. Most of the polyols used by industries are petrochemical based. In this project, a novel polyol from an orange peel oil-based derivative, limonene dimercaptan, was synthesized using one step photochemical thiol-ene reaction. The synthesized polyol was used to prepare flame retardant polyurethane …

Biowaste Derived Rigid Polyurethane Foams And Supercapacitors: A Renewable And Sustainable Alternative For Petrochemicals, Charith K. R. Akurana Gamaralalage

Electronic Theses & Dissertations

Bio-based polyol for rigid polyurethane (PU) foams and porous structured carbon as an electrode material for supercapacitors were synthesized from readily available biowaste precursor (orange peel) as an alternative to currently used petroleum-based starting materials. Synthesized bio-based polyols were characterized using FTIR, GPC, hydroxyl number, and viscosity measurements. These analyses indicated that intended bio-based polyol was obtained via thiol-ene chemistry with a high yield. Rigid PU foams prepared from bio-based polyol exhibited density around 35 kg/m³, maintained a regular cell structure with uniform cell distribution, closed cell content over 90%, and excellent compressive strength of ~230 kPa, suggesting …

Synthesis And Characterization Of Molybdenum Sulfide And For Hydrogen Evolution Reaction And Supercapacitor Applications, Zhuo Wang

Electronic Theses & Dissertations

To meet the constantly rising requirement of energy other than traditional fossil fuel and environment protection, it is a perfect time to development low cost, and efficient materials for clean energy production. Hydrogen generation by water splitting is one of the cleanest ways to produce cheaper energy. Hydrogen evolution reaction (HER) is one of the key steps in water splitting process. Ideally, the thermodynamic potential for HER should be at 0 V (vs. SHE). However, without an efficient catalyst, this reaction occurred at higher potential, called overpotential. A good HER catalyst is needed to lower the overpotential and hence to …