Speaker
Description
The insufficient green production of hydrogen is a bottleneck in the development of a sustainable hydrogen network. Electrolytic water splitting in acidic electrolytes addresses this problem by making use of the intermittent nature of renewable energies to produce hydrogen at high pressures. The limiting process is the anodic oxygen evolution reaction (OER), which is plagued by high overpotentials and electrode degradation. We have studied the potential-driven restructuring of Ir oxides in 0.1 M H$_{2}$SO$_{4}$ during the oxygen evolution reaction using pulse voltammetry, operando soft X-ray absorption spectroscopy and density functional theory (DFT). (Poster AC 2.1)
In the framework of the BMBF project PrometH2eus we are investigating Ni based electrodes in the oxygen evolution reaction in alkaline electrolytes. In order to enable the assignment of the X-ray photoelectron spectroscopy (XPS) features we have first performed ambient pressure studies of Ni samples in oxygen and water atmospheres. The results will be compared to DFT calculations. First operando studies XPS studies have been performed under OER conditions. (Poster AC2.2)
In the framework of the DFG Transregio 247 we investigate the electronic structure of Cobalt oxides, CoFe spinels, Cobalt containing perovskites by operando X-ray spectroscopy in the soft energy range and by electron microscopy under reaction conditions. In addition the samples are studied as electrodes in the oxygen evolution reaction using the same techniques. (Poster AC 2.3)
The selective oxidation reaction of ethylene over Ag catalyst is very attractive due to the economic importance of ethylene oxide (EO) as a versatile chemical intermediate. The nature of the oxygen species that can produce EO on Ag catalysts have been recently identified as originating from adsorbed SO$_{4}$. NAP-XPS experiments demonstrated that the EO selectivity tracks the coverage of SO$_{4}$. In contrast to ethylene epoxidation, SO$_{4}$ is titrated under propylene oxidation conditions and SO$_{3}$ is seen as a titration product. The co-existence of SO$_{4}$ and atomic O on the Ag surface appears to dictate the (high) EO and (low) PO selectivity. (Poster AC 2.4)
| Abstract Number (department-wise) | AC 2.0 |
|---|---|
| Department | AC (Schlögl) |
