CAS: Innovating New Strategies for Selective Electrocatalytic Reduction

With the support of the Chemical Catalysis program in the Division of Chemistry, Dr. Jenny Y. Yang of the University of California, Irvine is studying new methods to improve the performance of catalysts that use electrical energy for chemical transformations.

Electricity-driven catalysts have many potential economic and environmental advantages over conventional thermal catalysts. They often function under milder conditions, are more energy efficient, and generate less chemical waste. They also have a smaller carbon footprint if operated using renewable electricity.

However, some catalysts often convert water to hydrogen as an undesirable side reaction that wastes energy. The proposed study seeks to develop and test catalyst design strategies to inhibit hydrogen evolution while achieving higher yields of the desired products. The concepts will be applied to catalysts that can recycle CO2 into useful products.

However, these design strategies are general, and the studies have broader potential to improve the performance of all electricity-driven catalysts. These studies will also provide excellent training for undergraduate and graduate researchers and postdoctoral associates in multiple topics directly relevant to training the next-generation scientific work force.

In addition to building expertise in state-of-the-art experimental techniques, they will also develop skills in critical thinking, hypothesis-driven experimental design, and written and oral communication. Additionally, the researchers will work in a highly collaborative team atmosphere that works towards common goals.

With the support of the Chemical Catalysis program in the Division of Chemistry, Dr. Jenny Y. Yang of the University of California, Irvine is studying new strategies for selective electrocatalytic reduction.

Electrochemical methods for reduction have several advantages over the use of stoichiometric reductants. These include the ability to dial in a redox potential to elicit greater reaction selectivity, fewer operational hazards and reduced chemical waste. However, electrochemical and electrocatalytic reduction reactions that require protons often suffer from low Faradaic yields due to direct proton reduction to hydrogen.

The challenge of product selectivity over hydrogen evolution is pervasive throughout electrochemical reduction reactions. The studies will pursue catalyst design strategies to kinetically suppress proton reduction while not inhibiting the reduction of desired substrates. The strategies will be tested on complexes designed to have CO2 reduction activity.

Electrocatalytic CO2 reduction toward fuels is important as a mechanism for renewable energy storage and transport. Thus, the proposed research will concurrently develop guidelines for mediating electrochemical reduction and result in new catalysts and mechanistic insights into CO2 reduction to fuels. However, the design strategies are generalizable to a broad range of catalysts, from electro-organic reduction to other feedstock-to-fuel reductions.

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.