(Keynote) Theoretical Inspirations from Radoslav Adzic’s Electrocatalysis Work
Authors: Mavrikakis Manos , Elnabawy Ahmed O. , Roling Luke T. , Herron Jeff A. 
Published: February 2020

When combined with controlled synthesis of well-defined facets and shapes, density functional theory (DFT) could give especially accurate descriptions of electrocatalytic reactions on surfaces. Dr. Adzic’s group has pioneered the controlled and uniform deposition of a monolayer (or overlayers) of Pt on a single crystal or nanoparticles of another transition metal or transition metal alloys.1-6 Not only does this morphology achieve better utilization of the overlying Pt atoms, but the resulting structures also possess remarkable stability as electrocatalysts. Here, we review our long-standing collaboration with Dr. Adzic on the oxygen reduction reaction (ORR) over Pt monolayer or overlayers atop a variety of transition metals5,7-12, as well as the electrooxidation of formic acid on Pt monolayers on single-crystals of transition metals. A logical extension of this methodology is to support Pt overlayers atop shape-selected nanoparticles, which selectively expose well-defined facets. Time-permitting, we will also be discussing insights from studying ORR of Pt overlayers on Pd icosahedra13, octahedra14, and nanocubes15. In several cases, the induced compressive strain and ligand effects that the Pt monolayer or overlayers experience on various substrates weaken the adsorption of oxygenated species (e.g.: OH) compared to pure Pt, thereby enhancing the ORR activity.

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