Time: 12:00 a.m.
Place: Materials Day 2013, Ruhr-Universität Bochum, Bochum, Germany
Artjom Maljusch, Ruhr-Universität Bochum, Bochum, Germany
John Henry, Ruhr-Universität Bochum, Bochum, Germany
Aliaksandr Bandarenka, Ruhr-Universität Bochum, Bochum, Germany
Wolfgang Schuhmann, Ruhr-Universität Bochum, Bochum, Germany
The ability to experimentally probe surface properties is a vital component for the design and development of novel high performance catalysts. To obtain information about fundamental surface properties such as e.g. the work function of the sample surface and its local electrochemical activity, an integrated Scanning Kelvin probe (SKP) - Scanning Electrochemical Microscope (SECM) system was developed . The combined SKP-SECM system is a unique tool able to perform experiments in both modes of operation using the same Pt SKP-SECM tip over exactly the same position on the sample surface without the need for sample replacement.
To evaluate the correlation between the Volta potential difference and local catalytic activity for O2 reduction reaction, a Cu-Pt(111) near surface alloy , which is one of the most active ORR catalysts reported to date, was formed on the surface of a recently developed Pt(111)-like thin film electrode . The consumption of molecular oxygen on the surface of the prepared catalyst was in-situ visualized in the redox-competition mode of the SECM (RC-SECM). The obtained results indicate the existence of a correlation between the work function and materials catalytic activity illustrating the ability of integrated SKP-SECM system to provide essential information for the efficient design of novel catalytic materials. The development of the integrated SKP-SECM system, the preparation, characterization and investigation of the catalytic activity of the prepared ORR catalysts will be presented and discussed in detail.