User research at BESSY II: Formation of a 2D meta-stable oxide in reactive environments

Illustration of a Cu<sub>x</sub>O<sub>y</sub> structure formed on a AgCu alloy in oxidizing environments described in this work. (c) ACS Applied Materials &amp; Interfaces.

Illustration of a CuxOy structure formed on a AgCu alloy in oxidizing environments described in this work. (c) ACS Applied Materials & Interfaces. © (2020) ACS Publishing

The chemical behaviour of solid material surfaces is an important physical characteristic for applications of catalysis, chemical sensors, fuel cells and electrodes. A research team from the Max Planck Institute for Chemical Energy Conversion has now described an important phenomenon that can occur when metal alloys are exposed to reactive environments at the synchrotron source BESSY II.

In a recent work published in ACS Applied Materials & Interfaces, a researchers’ team led by Dr. Mark Greiner (Surface Structure Analysis, Department of Heterogeneous Reactions) demonstrates an important phenomenon that can occur when metal alloys face reactive environments. They can form meta-stable 2D oxides on their surfaces. Such oxides exhibit chemical and electronic properties that are different from their bulk counterparts. Due to their meta-stability, their existence is also difficult to predict.

This publication displays the results of a thorough investigation of one such oxide, confirming previous theoretical predictions of its existence, and helps to advance the understanding of the complexity of solid surfaces in reactive environments. The investigations were performed using in-situ photon electron spectroscopy at the ISISS beamline and the UE49-PGM beamline at BESSY II.

This investigation was a collaborative research effort between the Max Planck Institute for Chemical Energy Conversion, the Max-Planck-Institut für Eisenforschung, the Fritz Haber Institute of the Max Planck Society, the Helmholtz Zentrum Berlin and the Italian National Research Council Institute of Materials (CNR-IOM).

(sz/Max-Planck-Institut für chemische Energiekonversion)


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