Hydrogen dissociation on metal surfaces - a model system for reactions on surfaces

Abstract

Reactions on surfaces play an important role in many technological applications. Since these processes are often rather complex, one tries to understand single steps of these complicated reactions by investigating simpler system. In particular the hydrogen dissociation on surfaces serves as such a model system. There has been much progress in recent years in the theoretical description of reactions on surfaces by high-dimensional dynamics simulations on potential energy surfaces which are derived from ab initio total energy calculations. In this brief review I will focus on the hydrogen dissociation on the clean and sulfur-covered Pd(100) surface. These calculations established the importance of dynamical concepts like the steering effect. The electronic structure calculations allow furthermore the determination of the factors that determine the reactivity of a particular surface. This will be demonstrated for the poisoning of hydrogen dissociation by sulfur adsorption on the Pd(100) surface. In addition, quantum effects in the dynamics can be assessed by comparing the results of classical with quantum dynamical calculations on the same potential energy surface. 68.35.Ja, 82.20.Kh, 82.65.Pa

Rotational and Vibrational Excitations of a Hydrogen Molecule Trapped within a Nanocavity of Tunable Dimension

“…3(b)]. The increase of vibration energy suggests a strengthened bonding of the molecule to the substrate, which weakens the H-H bond and increases the bond length as predicted by theoretical calculations [22,23]. DFT calculations of the adsorption energy and H-H bond length at different tip-substrate separations have been performed [ Fig.…”

Molecular Simulation of Dissociation Phenomena of Gas Molecule on Metal Surface

“…It was reported that hydrogen dissociation on Cu(111) surface requires at least around 0.5 eV of large activation energy (Luntz, 2009;Gross, 1998). Moreover, it was also reported both theoretically and experimentally that the dissociation probability is high at 0 translational energy and decreases along with the translational energy and increases at higher energy again on Pd(100) surface (Luntz, 2009;Gross, 1998). From the above discussion, MD simulations using the constructed EAM potential are capable of simulating molecular beam experiments to a certain degree.…”

Diamond Nanowires: Fabrication, Structure, Properties and Applications

“…Hydrogen plays an important role in the formation of the diamond nanowires since it can facilitate the transformation of sp and sp 2 bonds into sp 3 bonds [92]. Meanwhile, transition metals (Fe in this experiment) are known to facilitate the dissociation of hydrogen molecules into atomic hydrogen at significant low hydrogen dissociation barrier [93,94]. The authors summarized their achievement in a mini-review, and gave a possible formation process of the diamond nanowires [95].…”