A thermodynamics study of hydrogen interaction with (110) transition metal surfaces

An in-depth understanding of the interactions between hydrogen and transition metal catalysts is of great significance in exploring novel heterogeneous hydrogenation reaction mechanisms. Herein we present a comprehensive study of the interactions of hydrogen on active metal surfaces by using a multiscale method. Six different transition metals of Ni-group and Cu-group are considered. Different from two stable (11 1) and (1 0 0) surfaces, the energetic results of hydrogen species diffusing on and permeating into the active (1 1 0) surfaces are fully addressed from three-dimensional potential energy surfaces and density functional theory calculations. Ab initio thermodynamics calculations show that a stable adsorption phase diagram with full hydrogen coverage preferably forms with decreasing reaction temperature and increasing hydrogen partial pressure, especially on the (1 1 0) surfaces of Ni-group metals without consideration of the reconstruction events. During the evolutions of metal nanoparticles under moderate reaction conditions, the active (1 1 0) surface is difficult to be exposed for Ni-group metal nanoparticles, while for Cu-group metal nanoparticles it is easy to get exposed. These important thermodynamic results will contribute to an in-depth understanding of the interactions between hydrogen species and transition metal catalysts in heterogeneous catalysis.

Automated summary

An in-depth understanding of the interactions between hydrogen and transition metal catalysts is crucial for exploring novel heterogeneous hydrogenation reaction mechanisms. This study comprehensively investigates the interactions of hydrogen on active metal surfaces, revealing differences between Ni-group and Cu-group transition metals and the effects of reaction temperature and hydrogen partial pressure on stable adsorption phase diagrams. Additionally, the evolution of metal nanoparticles under moderate reaction conditions differs between Ni-group and Cu-group metals.