Catalysis and Reaction Engineering Commons^™

Pd-Based Hydrogen Separation Membranes Synthesized Via A Liquid-Phase Route, Chase W. Thompson

Chemical and Biological Engineering ETDs

Palladium (Pd) membranes have gained significant attention for their ability to selectively separate hydrogen, a critical process for clean energy applications such as fuel cells and hydrogen storage. However, challenges such as grain growth, sintering, hydrogen embrittlement, and film uniformity limit their scalability and long-term stability. This thesis focuses on the controlled synthesis, deposition, and stability of Pd nanoparticles to optimize membrane performance for hydrogen separation. This work investigates solution-phase synthesis of Pd nanoparticles, focusing on temperature, precursor concentration, and solvent composition as key variables influencing particle growth and dispersion. Pd membranes were fabricated using nanoparticle deposition onto porous supports, …

Mg And Fe Co-Doped Perovskites For The Electrochemical Oxidative Coupling Of Methane In Solid Oxide Electrolyzers, Luke H. Denoyer

Chemical and Biological Engineering ETDs

More efficient usage of shale gas reserves and natural gas resources will allow for higher olefin yields and lower greenhouse gas emissions. The oxidative coupling of methane (OCM) is a direct pathway for converting methane to ethylene at temperatures >700 °C. The OCM process is typically regulated via the choice of catalyst, reactor conditions, temperature range and gas mixing. The electrochemical oxidative coupling of methane (E-OCM) is a modification to the OCM reaction by controlling the oxygen content via externally applied potentials to an SOEC. Perovskite oxide catalysts are useful for E-OCM due to their flexible bond networks and desired …

An Investigation Of The Chemistry, Thermodynamics And Catalytic Activity Of Molybdenum Carbides, Shanti Kiran Nayak

Chemical and Biological Engineering ETDs

These studies investigate the chemistry and stability of molybdenum carbides as an electrocatalyst. Due to their unique electronic properties, molybdenum carbides are purposed as electrocatalysts for reaction systems such as hydrogen evolution reaction, bifunctional water splitting and CO oxidation.

In this study, various synthesis processes were utilized to produce different types of molybdenum carbide with varying properties of particle size, surface area and excess carbon. The samples characterized by XRD accompanied by Whole Profile Fitting, Electron Microscopy, Gas Adsorption (surface area) and XPS.

These synthesis processes were refined using fundamental thermodynamic analyses. These analyses highlight regions of stability of different …

Microbial Desalination Cells With Efficient Platinum Group Metal-Free Cathode Catalysts, Morteza Rezaei Talarposhti

Chemical and Biological Engineering ETDs

Iron-nitrogen-carbon based catalyst was used at the cathode of a microbial desalination cell (MDC) and compared with platinum (Pt) and activated carbon (AC) cathode. Fe-N-C catalyst was prepared using nicarbazin (NCB) as organic precursor by sacrificial support method (SSM). Rotating ring disk electrode (RRDE) experiments shows that Fe-NCB had higher electrocatalytic activity compared to AC and Pt. The utilization of Fe-NCB into the cathode improved substantially the performance output with initial maximum power density of 49±2 μWcm^-2 in contrast to Pt and AC catalysts which have shown lower values of 34±1 μWcm^-2 and 23.5±1.5 μWcm^-2, respectively. …

Activity Of Pgm-Free Electrocatalysts For Oxygen Reduction Reaction: Ph And Co-Catalysis Effects, Mario Santiago Rojas Carbonell 8148369

Chemical and Biological Engineering ETDs

Fuel cells offer a source to the current and always increasing demand for electric power. But as any new technology, there are challenges that need to be addressed to render it feasible for the market place. One of this challenges is finding the appropriate materials to catalyze the oxygen reduction reaction (ORR) that occurs in the cathode. Oxygen is used as an oxidant in a significant portion of the fuel cells due to its readily availability and high reduction potential. Now, one the bottlenecks that stops the large-scale adoption is the expensive and rare metals that have been used as …