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Catalytic Activity and Stability of Metal Nanoparticles from First-Principles Theory Wei-Xue Li Department of Chemical Physics, Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China. [email protected] To develop efficient heterogeneous catalyst with higher mass specific activity and stability is challenging, yet demanding nowadays due to the limited resources available for energy conversion, chemical production, and environment protection. To increase the mass-specific activity, the most used strategy is to reduce the particle size and thus to expose more surface sites. This applies particularly well for structural insensitive reactions, with cost of the increased tendency of sintering and/or disintegration of supported particles. For some of the structure sensitive reactions, the activity in term of for instance turn-over-frequency might even decrease with a reduction of the particle size. Shape-control to expose specific facets with desired activity and higher site density is a promising strategy; however, the performance of catalysts is often degraded by the strong protecting agents used to expose specific facets of catalysts. Rational design of catalysts exposing abundant active sites yet stable for a high specific activity remains a challenge. To approach this goal, density functional theory (DFT) calculations were carried out to explore the structural sensitivity of crystal phases of transition metals on molecule activation. The great influence of crystal structure and corresponding morphology effect on formation of the various active sites with distinct intrinsic activity and density will be presented. Finally, I will present our latest development on stabilization of the supported nanoparticles, slowing down the kinetics of sintering by modulation of the metal-support interfacial interaction and particle size distribution. The influence of the reaction environment (temperature and pressure) on stability will be discussed. Reference: 1. R. H. Ouyang, J. X. Liu, W. X. Li, Atomistic Theory of Ostwald Ripening and Disintegration of Supported Metal Particles under Reaction Conditions, J. Am. Chem. Soc. 2013, 135 1760-177 2. J. X. Liu, H. Y. Su, D. P. Sun, B. Y. Zhang, W. X. Li, Crystallographic Dependence of CO Activation on Cobalt Catalysts: HCP versus FCC, J. Am. Chem. Soc. 2013, 135, 16284-16287 3. W. Z. Li, J. X. Liu, J. Gu, W. X. Li, Y. W. Zhang, D. Ma, Chemical Insights into the Design and Development of Face-Centered Cubic Ruthenium Catalysts for Fischer-Tropsch Synthesis, J. Am. Chem. Soc. 2017, 139, 2267-2276