Electron-Transfer-Induced Dissociation of H₂on Gold Nanoparticles: Excited-State Potential Energy SurfacesviaEmbedded Correlated Wavefunction Theory

Abstract

Plasmons / Photocatalysis / Potential Energy SurfacesNoble metal surfaces play a central role in heterogeneous catalysis. Lasers of the appropriate resonance frequency efficiently generate surface plasmons. These, in turn, may generate hot electrons, which can drive catalytic reactions at low temperatures. In this work, we demonstrate how embedding methods allow for the use of accurate ab-initio correlated wavefunction methods to describe excited-state potential energy surfaces of molecule-surface interactions. As model system, we consider the hot-electron-induced dissociation of hydrogen on Au(111), which has recently been demonstrated experimentally. We discuss merits and limitations of several different correlated wavefunction schemes. Our results show that dissociation barriers may be substantially reduced upon electron excitation and suggest a method to calculate the hot electron energies required for catalytic reactions.

Reactive and Nonreactive Scattering of HCl from Au(111): An Ab Initio Molecular Dynamics Study

“…At the HCl–Au(111) TS, GGA-DFT leads to an electron transfer from the surface to the molecule of 0.3 electrons, 17 and at this level of DFT, this could lead to an underestimate of the barrier height. We suggest using an electronic structure method of which the accuracy is not adversely affected by charge transfer between the surface and the molecule, such as diffusion Monte-Carlo 65 or density functional embedded wave function theory, 66,67 to investigate the reaction barrier height for HCl + Au(111). Second, it is possible that with the present IAA-LDFA theory, we are not yet quantitatively describing nonadiabatic effects on this reaction.…”

“…This suggests that the barrier height to dissociative chemisorption should be substantially higher than obtained with GGA-DFT, whether or not the correlation functional is replaced with a van der Waals correlation functional, to achieve a quantitative description of experiment. We therefore suggest that an electronic structure method of which the accuracy is not adversely affected by charge transfer between the surface and the molecule, such as diffusion Monte-Carlo 65 or density functional embedded wave function theory, 66,67 should be used to investigate the reaction barrier height for HCl + Au(111). The latter has very recently been applied in the development of a six-dimensional PES for the O 2 + Al(111) system, 68 which has successfully captured the activated feature and steric effect that are observed experimentally but absent with GGA-DFT calculations.…”

Dynamics of H2 dissociation on the close-packed (111) surface of the noblest metal: H2 + Au(111)

“…The requirement on the barrier geometry discussed above would suggest looking at the interaction of H 2 with the "noblest" metals, i.e., Au 27 and Ag. Calculations using density functional theory (DFT) put the minimum barrier for H 2 dissociation on Au (111) well above 1 eV, 27,28 and put the barrier position at an H-H distance of about 1.2 Å. 28 The values are significantly larger than the well established values of the minimum barrier height and position of H 2 + Cu(111) (0.63 eV and 1.03 Å, respectively 19 ).…”

“…Calculations using density functional theory (DFT) put the minimum barrier for H 2 dissociation on Au (111) well above 1 eV, 27,28 and put the barrier position at an H-H distance of about 1.2 Å. 28 The values are significantly larger than the well established values of the minimum barrier height and position of H 2 + Cu(111) (0.63 eV and 1.03 Å, respectively 19 ). DFT calculations on the H 2 + Ag(111) system 29 suggest barrier characteristics (1.16 eV, H-H distance of 1.26 Å) very similar to those of H 2 + Au (111), and H 2 + Ag (111) might therefore also be a good model system for observing non-adiabatic effects on reaction.…”

Implementation of density functional embedding theory within the projector-augmented-wave method and applications to semiconductor defect states

“…The density functional embedding scheme has been successfully applied to studying absorbates (such as H 2 or O 2 ) on metal surfaces, including Al and Au. [14][15][16] While it has been shown that the embedded metal cluster can decently reproduce bulk metal properties, the accuracy of the density functional embedding method beyond metallic systems has been tested sparingly. 17 Several other embedding schemes have been applied to systems featuring more covalent bonding character, in both molecules and condensed matter.…”