Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 5 of 5
Full-Text Articles in Engineering
The Controlled Synthesis Of Hydrogen Electrocatalysts For Alkaline Exchange Membrane Fuel Cell And Electrolysis Applications Via Chemical Vapor Deposition, Stefan Thurston Dubard Williams
The Controlled Synthesis Of Hydrogen Electrocatalysts For Alkaline Exchange Membrane Fuel Cell And Electrolysis Applications Via Chemical Vapor Deposition, Stefan Thurston Dubard Williams
Doctoral Dissertations
The development of catalysts for the electrochemical processes of hydrogen systems (e.g., fuel cells and electrolyzer systems) continues to be an attractive area of research for renewable energy technologies. One significant challenge has been developing hydrogen catalysts suitable for alkaline environments, mainly due to the sluggish kinetics of hydrogen reactions. In alkaline environments, the kinetics are decreased by two orders of magnitude when compared to acidic environments. Chemical vapor deposition (CVD) is a conventional method used to synthesize these types of catalysts. This effort discusses extending work being done using a modified CVD process known as “Poor Man’s” CVD (PMCVD) …
Process Intensification Of Fuel Synthesis And Electrolysis, Jeremy Lee Hartvigsen
Process Intensification Of Fuel Synthesis And Electrolysis, Jeremy Lee Hartvigsen
Doctoral Dissertations
”As more renewable energy is added to the electric grid, energy storage becomes a high priority. Suggestions have been made for energy storage in the form of fuel and chemicals. Currently, Solid Oxide Electrolysis systems can operate in endothermic mode and reduce the electrical requirement by supplying heat. Fuel synthesis from syngas is exothermic and can supply heat. However, the temperature mismatch in the normal operation of the electrolysis step and fuel synthesis step makes the direct utilization of this heat impossible. This work explores possibilities of alternate arrangements of coupling electrochemical systems and chemical synthesis. This work also explores …
Computational Study Of Sodium Magnesium Hydride For Hydrogen Storage Applications, Fernando Antonio Soto Valle
Computational Study Of Sodium Magnesium Hydride For Hydrogen Storage Applications, Fernando Antonio Soto Valle
Doctoral Dissertations
Hydrogen offers considerable potential benefits as an energy carrier. However, safe and convenient storage of hydrogen is one of the biggest challenges to be resolved in the near future. Sodium magnesium hydride (NaMgH 3) has attracted attention as a hydrogen storage material due to its light weight and high volumetric hydrogen density of 88 kg/m3. Despite the advantages, hydrogen release in this material occurs at approximately 670 K, which is well above the operable range for on-board hydrogen storage applications. In this regard, hydrogen release may be facilitated by substitution doping of transition-metals. This dissertation describes first-principles computational methods that …
Adsorption And Diffusion Of Gases In Nano-Porous Materials, Nethika Sahani Suraweera
Adsorption And Diffusion Of Gases In Nano-Porous Materials, Nethika Sahani Suraweera
Doctoral Dissertations
In this work, a systematic computational study directed toward developing a molecular-level understanding of gas adsorption and diffusion characteristics in nano-porous materials is presented. Two different types of porous adsorbents were studied, one crystalline and the other amorphous. Physisorption and diffusion of hydrogen in ten iso-reticular metal-organic frameworks (IRMOFs) were investigated. A set of nine adsorbents taken from a class of novel, amorphous nano-porous materials composed of spherosilicate building blocks and isolated metal sites was also studied, with attention paid to the adsorptive and diffusive behavior of hydrogen, methane, carbon dioxide and their binary mixtures. Both classes of materials were …
Protein Engineering For The Enhanced Photo-Production Of Hydrogen By Cyanobacterial Photosystem I, Ifeyinwa Jane Iwuchukwu
Protein Engineering For The Enhanced Photo-Production Of Hydrogen By Cyanobacterial Photosystem I, Ifeyinwa Jane Iwuchukwu
Doctoral Dissertations
Photosystem I (PSI) from plants, algae, and cyanobacteria can mediate H2 evolution in vivo and in vitro. A simple, self-platinization procedure that permits stable PSI-mediated H2 evolution in vitro has been developed. The H2 evolution capabilities of PSI from Thermosynechococcus elongatus have been characterized. This organism utilizes cytochrome c6 (cyt c6) as the e- donor to P700. Using a solution-based, self-organized platinization of the PSI nanoparticles, this study demonstrates a sodium ascorbate-cyt-PSI-Pt-H2 electron transport and proton reduction system that yields light-dependent H2. The system was thermostable with H2 evolution increasing up to 55°C. In addition, stability studies have shown the …