Electrocatalysis

Synthesis of well-defined multimetallic nanostructures is critical in discovering catalysts to replace platinum for the electrochemical oxygen reduction reaction. The synthesis of these nanostructures is often complicated by incompatibility of metals, dynamic reconstruction under operating conditions, and general characterization of the nanoparticles. Recently, we developed a synthesis in which we encountered and overcame these obstacles. We worked on improving alkaline ORR activity of Ag-based materials. While silver is less active material than Pt, it is also much less expensive. By improving the ORR activity of silver through alloying, we can make materials that are more competitive with Pt on a cost basis. Motivated by density functional theory calculations, we developed a synthesis to prepare Ag-Co nanoparticles that show superior ORR performance compared to monometallic Ag nanoparticles.

Our group focuses on understanding the interactions between plasma and liquids, a process known as plasma-driven solution electrolysis. By identifying the dominant reactive species, we can explore the unique opportunities presented by these highly reactive interfaces to drive both reductive and oxidative reactions. We demonstrated the feasibility of this type of chemistry in the synthesis of propylene oxide from propylene and water, where the hydrogen peroxide generated from plasma-liquid interaction serves as a selective oxidant for propylene towards propylene oxide. Current members working in this area include Han-Ting Chen and Yi Zhang