ME Seminar Series: The Next Evolution in Water Oxidation
John Kitchin, Carnegie Mellon University
Electrochemical water oxidation may play a crucial role in future renewable energy systems for energy storage, fuel synthesis, and integration with oxycombustion systems. Some outstanding challenges in efficiently oxidizing water remain, including the overly high energetic cost of water electrolysis, and the high cost of materials that perform moderately well. Many efforts have focused on searching for new oxidebased materials with enhanced performance, but no exceptional material has been found to date that is substantially better than known materials. We will show a simple model based on thermodynamics and parameterized by density functional theory that suggests there is an upper bound in activity oxide-based materials that may explain why substantially better materials have not yet been found, and that suggests what must be done to find better materials. We will highlight some challenges in the accuracy of the model, both on the experimental side of what is actually modeled, and on the computational side of the methods used for the modeling. We will illustrate a new, more accurate computational methodology and our plans to use that in pushing the next evolution in water oxidation forward.