Utilizing the Surface Electrostatic Potential to Predict the Interactions of Pt and Ni Nanoparticles with Lewis Acids and Bases—σ-Lumps and σ-Holes Govern the Catalytic Activities

High Resolution Image Download MS PowerPoint Slide An improved understanding of the interactions of transition-metal (TM) nanoparticles with Lewis acids/bases will facilitate the design of more efficient catalysts. Therefore, Pt 14, Pt 13, Pt 12, and Ni 12 nanoparticles have been studied at the TPSSh/Def2-TZVP level of density functional theory (DFT). Surface electrostatic potential [ V S ( r )] maps are used to analyze the Lewis acidic and basic properties of all nanoparticles and indicate that the interactions of Pt and Ni nanoparticles are governed by σ d - holes and σ s - holes, respectively. Lewis acids (Na +, HF) and a Lewis base (H 2 O) have been tested as ligands to probe the local interaction proficiencies. The comparison between binding energies and V S ( r ) shows that the lowest minimum ( V S,min ) and highest maximum ( V S,max ) of V S ( r ) on each particle can predict the most favorable binding site for the Lewis acids and base, respectively. V S,min can also rank the different binding strengths of Na + and HF with the nanoparticles. For H 2 O, the binding strength versus V S,max correlation is better for Ni 12 than for the Pt nanoparticles. This observation is discussed in relation to charge transfer/polarization and structural deformation upon interaction. In light of our findings, we compare the catalytic potential of Ni to the less abundant but more commonly used Pt.