Related papers: CO oxidation at Pd(100): A first-principles constr…
The turn-over frequency of the catalytic oxidation of CO at RuO2(110) was calculated as function of temperature and partial pressures using ab initio statistical mechanics. The underlying energetics of the gas-phase molecules, dissociation,…
We present lattice-gas modeling of the steady-state behavior in CO oxidation on the facets of nanoscale metal clusters, with coupling via inter-facet CO diffusion. The model incorporates the key aspects of reaction process, such as rapid CO…
Heating a long-range ordered adsorbate phase beyond its stability temperature does not necessarily result in a disordered phase, it can also break up into heavily fluctuating ordered domains. Temporal and/or spatial averaging over these…
Thin films of transition metal oxides open up a gateway to nanoscale electronic devices beyond silicon characterized by novel electronic functionalities. While such films are commonly prepared in an oxygen atmosphere, they are typically…
A thin liquid film covered with an insoluble surfactant in the vicinity of a first-order phase transition is discussed. Within the lubrication approximation we derive two coupled equations to describe the height profile of the film and the…
Surface states refer to electronic states emerging as a solid material terminates at a surface, and can be present in many systems. Despite their spatial proximity to material surfaces, surface states have been largely overlooked in…
We present a multi-lattice kinetic Monte Carlo (kMC) approach that efficiently describes the atomistic dynamics of morphological transitions between commensurate structures at crystal surfaces. As an example we study the reduction of a…
Using density-functional theory in combination with a thermodynamic formalism we calculate the relative stability of various structural models of the polar O-terminated (000-1)-O surface of ZnO. Model surfaces with different concentrations…
Understanding of the complex behavior of particles at surfaces requires detailed knowledge of both macroscopic and microscopic processes that take place; also certain processes depend critically on temperature and gas pressure. To link…
Combining high-resolution core-level spectroscopy (HRCLS), scanning tunneling microscopy (STM) and density-functional theory (DFT) calculations we reanalyze the Pd(100)-(SQRT(5) x SQRT(5) R27^o)-O surface oxide phase. We find that the…
This study investigates two critical aspects of the gas sensing mechanism in metal oxide sensors: (1) the conditions that maximize chemisorbed oxygen concentration as a function of temperature and oxygen partial pressure, and (2) which…
The durability of passivable metals and alloys is often limited by the stability of the surface oxide film, the passive film, providing self-protection against corrosion in aggressive environments. Improving this stability requires to…
We present a density-functional theory based kinetic Monte Carlo study of CO oxidation at the (111) facet of RuO$_2$. We compare the detailed insight into elementary processes, steady-state surface coverages and catalytic activity to…
Silicon together with its native oxide SiO$_2$ was recognized as an outstanding material system for the semiconductor industry in the 1950s. In state-of-the-art device technology, SiO$_2$ is widely used as an insulator in combination with…
We present a first-principles based multiscale modeling approach to heterogeneous catalysis that integrates first-principles kinetic Monte Carlo simulations of the surface reaction chemistry into a fluid dynamical treatment of the…
The formation of ultrathin oxide layers on metal surfaces is a non-thermally-activated process which takes place spontaneously at very low temperatures within nanoseconds. This paper reports mechanistic details of the initial oxidation of…
As a first step towards understanding the morphology of PdO crystals we performed a systematic full-potential density-functional theory study of all possible 1 x 1 terminations of the low-index surfaces of tetragonal PdO. Applying the…
We describe a first-principles statistical mechanics approach enabling us to simulate the steady-state situation of heterogeneous catalysis. In a first step density-functional theory together with transition-state theory is employed to…
Despite the common expectation that conjugated organic molecules on metals tend to adsorb in a flat-lying wetting layer, several recent studies have found strong indications for coverage-dependent transitions to upright-standing phases,…
In this study, the dynamic oxidation state changes of pure Pt and 50at% PtPd alloy catalysts were investigated during a temperature ramp from 80 to 450 C under a reactive gas mixture of 500 ppm NO and 3 % Oxygen in Nitrogen atmosphere.…