The Chemical and Biological Engineering Department is pleased to present student seminars by Ruihan Li and Kunhuan Liu as part of our ChBE Seminar Series.

Ruihan Li will present a seminar titled "Dynamics of Electrocatalytic Materials during Water Oxidation in Acid."

ABSTRACT: In pursuit of a sustainable energy landscape, electrocatalytic conversion processes, which enable the production of societally important fuels and chemicals, are envisioned to play an important role as we transition away from heavy reliance on fossil fuels. Hydrogen generated via water electrolysis is an increasingly attractive option for heavy freight and seasonal energy storage. However, the anodic oxygen evolution reaction (OER) poses challenges in terms of cost and energy efficiency, as the electrocatalytic materials that are both active and stable under oxidizing conditions in strong acid are limited to precious metal-based oxide, such as iridium. To understand material transformations in Ir-based catalysts and alternatives using earth-abundant metals that impact both activation and degradation processes, I employ two flexible electrocatalyst material platforms, specifically nonstoichiometric iridium-based material (Ca2IrO4) and Mn-based heteroanionic materials (Fe8-xMnxO10Cl3), allowing for systematic tuning of catalyst properties and probing their responses to well-controlled reaction conditions.

In the first part of my talk, I will highlight recent efforts to reveal changes in surface adsorbate energetics and local iridium structures with applied potentials using in situ x-ray absorption spectroscopy. Then, I will transition to manganese oxychlorides, correlating catalyst dynamics with OER behaviors by progressively probing the surface, near-surface, and bulk electronic and geometric structures.

Kunhuan Liu will present a seminar titled "Computational and Data-Driven Exploration of Metal-Organic Frameworks for High Capacity Cryogenic Hydrogen Storage."

ABSTRACT: Hydrogen is considered a crucial clean energy vector to mitigate climate change, but due to the low volumetric energy density of gaseous hydrogen, it is difficult to store hydrogen for many practical applications. Cryogenic sorption-based methods, particularly using nanoporous metal-organic frameworks (MOFs), have been considered as viable solutions to enhance the deliverable capacity of stored hydrogen. MOFs are a class of porous crystalline material synthesized from well-defined molecular building blocks (organic ligands and metal clusters) and exhibit tunable surface area and porosity.

This talk will focus on work combining computational methods and high-throughput screening to identify promising MOF candidates and structure-property relationships for hydrogen storage. In the first part of the work, I constructed in silico 105,764 MOF structures using 534 topologies and performed high-throughput screening of their hydrogen deliverable capacities using molecular simulations and surrogate machine learning models. Based on the analysis, I explored the effect of MOF topology on hydrogen deliverable capacity. We discovered that the best performing MOFs are generated with a set of topologies that have a low average deliverable capacity. I subsequently identified two mathematical descriptors of the topologies that best explain the pattern. In the second part of the work, I studied rht-MOFs that are based on supermolecular building blocks (SBBs). I showed that computational techniques can be used to explore a variety of SBBs, which are otherwise experimentally expensive to study. By exploring the structural space and elucidating the structure-property relationships in silico, we help focus the experimental efforts on the most promising materials.

Bagels and coffee will be provided at 9:30am, and the seminar will start at 9:40am. Please plan to arrive on time to grab a bagel and mingle!

*Please note that there will be no Zoom option for seminars this year.