Atomic-Scale View at the Segregation of Alkali Metals toward the KTaO(001) Perovskite Surface.

Perovskites exhibit outstanding performance in applications such as photocatalysis, electrochemistry, or photovoltaics, yet their practical use is hindered by the instability of these materials under operating conditions, specifically caused by the segregation of alkali cations toward the surface. The problem arises from the bulk strain related to different cation sizes, as well as the inherent electrostatic instability of perovskite surfaces. Here, we focus on atomistic details of the surface-driven process of interlayer switching of alkali atoms at the inorganic perovskite surface.

A model study of ceria-Pt electrocatalysts: stability, redox properties and hydrogen intercalation.

The electrocatalytic properties of advanced metal-oxide catalysts are often related to a synergistic interplay between multiple active catalyst phases. The structure and chemical nature of these active phases are typically established under reaction conditions, upon interaction of the catalyst with the electrolyte. Here, we present a fundamental surface science (scanning tunneling microscopy, X-ray photoelectron spectroscopy, and low-energy electron diffraction) and electrochemical (cyclic voltammetry) study of CeO(111) nanoislands on Pt(111) in blank alkaline electrolyte (0.

The Influence of Graded Amount of Potassium Permanganate on Corrosion of Hot-Dip Galvanized Steel in Simulated Concrete Pore Solutions.

This paper evaluates the amount of KMnO in simulated concrete pore solution (pH 12.8) on the corrosion behaviour of hot-dip galvanized steel (HDG). In the range of used MnO (10, 10, 10 mol·L), corrosion behaviour is examined with regard to hydrogen evolution and composition (protective barrier properties) of forming corrosion products.

Redox-mediated C-C bond scission in alcohols adsorbed on CeOthin films.

The decomposition mechanisms of ethanol and ethylene glycol on well-ordered stoichiometric CeO(111) and partially reduced CeO(111) films were investigated by means of synchrotron radiation photoelectron spectroscopy, resonant photoemission spectroscopy, and temperature programmed desorption. Both alcohols partially deprotonate upon adsorption at 150 K and subsequent annealing yielding stable ethoxy and ethylenedioxy species. The C-C bond scission in both ethoxy and ethylenedioxy species on stoichiometric CeO(111) involves formation of acetaldehyde-like intermediates and yields CO and COaccompanied by desorption of acetaldehyde, HO, and H.

Low-loading Pt/β-MoC catalyst for ethanol dissociation. Experimental and theoretical characterization.

The adsorption and dissociation of ethanol on Pt/β-MoC with a low noble metal loading (0.1 wt%) is studied in the context of catalytic H production from alcohols. X-ray diffraction and experimental results indicate that Pt modifies the lattice parameters of β-MoC.