Presenter(s): Nathan Stovall—Chemistry
Faculty Mentor(s): Shannon Boettcher, Raina Krivina S
ession 5: The Bonds that Make Us
Anthropogenic climate change has driven interest in the research and development of clean
energy alternatives . Great advancements in renewable energy production have been made, but its intermittent nature requires the development of a large-scale storage technology . Water electrolysis is a promising solution to the storage dilemma, via the state-of-the-art proton exchange membrane (PEM) electrolyzers that can convert renewable energy into hydrogen fuel . However, the acidic operating conditions of PEM cells results in slow kinetics of the oxygen evolution reaction (OER) . Iridium oxide is the only catalyst capable of withstanding these harsh conditions, but its low abundance and high costs limit large-scale implementation . My research focuses on designing a novel sub-monolayer-thick iridium oxide catalyst on an inexpensive conductive support that would allow to decrease iridium loading while maximizing activity . We have developed a novel synthetic method for adhering a cheap commercially available iridium precursor (IrCODCl dimer) to the surfaces of inexpensive acid-stable metal oxide nanoparticles . The mechanism of the assembly was investigated with UV-vis spectroscopy, X-ray photoelectron spectroscopy, and NMR . We discovered that the dimer attaches in a surface-limited manor allowing for precise control over the catalyst’s thickness . The determination of the mass loadings was accomplished via x-ray fluorescence and ex-situ inductively coupled plasma induced mass spectroscopy . Electrochemical measurements conducted in pH 1 have shown exceptionally high intrinsic activity at significantly reduced mass loadings . We are currently working on improving the catalyst’s stability which might in the future allow for industrial-scale implementation of water electrolysis as renewable energy storage .