CAREER: Designing 3-Dimensional Active Site Environments in Metal-Organic Frameworks for Oxygen Electrochemistry

Electrochemical reactions – such as those in fuel cells - play an important role in realizing an environmentally-sustainable, globally-scalable hydrogen economy. Catalysts are required to promote electrochemical reactions at practical rates. However, the high-cost and low-efficiency of current electrocatalysts has prevented large-scale adoption of electrochemical technologies.

While significant advances have been made in designing cheaper alternatives for the oxygen reduction reaction important in fuel cell catalysis, performance has plateaued over the past decade. The project focuses on a a new class of structurally-modified Metal Organic Framework catalysts (MOFs) that are not constrained by the limitations of current catalysts, thus opening the door to both lower-cost and higher-efficiency fuel cell technology.

The overall goal of this work is to establish bimetallic porphyrin-based MOFs (PMOFs) as a viable platform for future experimental and theoretical oxygen reduction reaction (ORR) studies. Multiscale molecular modeling approaches (including density functional theory, wave function theory and classical force fields) will be used to (1) screen MOF libraries and identify 3-D active sites that circumvent scaling relations, (2) develop methods to predict solvation effects within confined PMOF pores, and (3) quantify the various transport processes that are important for PMOF electrocatalysts.

Taken together these objectives will (1) assess the potential of using PMOFs for ORR and (2) generate fundamental insights related to various ubiquitous phenomena (i.e., solvation, O2 transport and charge transfer) in nanoporous materials. The software infrastructure and theoretical approaches employed will expand the boundaries of atomistic phenomena that can be studied computationally; these methods will be valuable to both the nanoporous materials and heterogeneous catalysis communities.

The research program is closely integrated with educational and outreach activities that focus on developing (1) a research-oriented Molecular Modeling Lab course and (2) virtual reality-based chemistry modules for K-12 students. The research-oriented course will help create a scientific mindset and instill a “lifetime of learning” for students, while the chemistry modules will improve K-12 student engagement and retention in STEM.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.