(689h) Computational Design of Sub-Surface Engineered Metal Oxides for Catalysis

Metal oxide-based catalysts have occupied a prominent place in heterogeneous catalysis, and are making a broad impact in the chemical industry as well as other energy and environmental applications. Extensive research efforts have been put forward to understand the nature of metal oxide as the catalyst itself as well as the support material for energy and chemical transformation.

In this talk, I will show that subsurface-engineered metal oxides(SEMO), where the subsurface layer(s) of a stable-inactive oxide are substituted or alloyed with another reactive oxide, not only hold the promise of meeting the desire for active, stable and cost-effective catalysts but also provide a versatile platform to study the structure-property relationship of metal oxides. As little as 1-2 unit cell of reactive oxide in the subsurface activates the otherwise inert surface. On the other hand, the capping layer consisted of a stable-inactive oxide protects the reactive components of the catalyst from degradation or dissolution under harsh chemical conditions. Using density functional theory, we have computational predicted several robust nano-catalysts the two half reactions for electrochemical water splitting: hydrogen evolution and oxygen evolution.¹

In the second half of my talk, I will demonstrate these SEMO can be used to effectively control the morphology of supported metal nanoparticles, including particle size and wetting. Genetic algorithm was employed for the global optimization of the metal nanoparticle supported on a number of SEMOs with different guest metals. Our findings suggest that SEMO can used as a versatile platform to study the metal-support interaction, where the support surface reducibility can be well deconvoluted from oxide support lattice. I will also show the application of SEMO supported NP in surface catalysis, such as reverse water-gas shift (RWGS) reaction.

(1) Akbashev, A. R.; Zhang, L.;et. al. Energy Environ. Sci.2018,11(7), 1762–1769.