Electrocatalytic activity of nanostructured electrodes
Systematic investigations of well-defined nanostructured systems are important tools to understand the mechanisms involved in electrochemical reactions of interest in electrocatalysis. In the first period of this project, the central topics have involved the investigation of diverse nanostructured electrodes using a synergetic combination of experiment and theory. We have applied our own theory of electrocatalysis to understand prototype reactions such as hydrogen evolution/oxidation reactions (HER/HOR) on sub-monolayers and monolayers of foreign atoms on gold and silver basal single crystals. We have investigated high index vicinal single crystal surfaces of silver with an accurate variation of step densities.
Our theoretical calculations have revealed that deposition of Rh atoms on Au and Ag electrodes should result in excellent electrocatalysts. Therefore, we started to study the decoration of these surfaces with rhodium and platinum by electrochemical deposition, which will be one of the central topics of the second period of the project. We have found that the anions play an important role in both the HER/HOR and in the decoration with foreign atoms. Henceforth, in the second period of the project, we also plan to investigate the influence of anions on these processes by experimental and theoretical approaches. We shall compare the behaviour of electrochemical deposition with decoration by controlled evaporation in a vacuum system. A combination of our own theory of
electrocatalysis with density functional theory (DFT) and molecular dynamics will be used to investigate the different steps of the HER/HOR and the stability of nanostructured electrodes resulting from decoration with foreign atoms in an electrochemical environment.
According to the experiments and predictions from theory, the focus will be oriented to selected systems that promise to be stable and show a large catalytic activity.
- Dr. Elizabeth Santos
- Inst. of Theoretical Chemistry
- Ulm University
- Albert-Einstein-Allee 11
- D-89069 Ulm
- Telephone: +49 (0)731/50 31342
- Telefax: +49 (0)731/50 22819
- E-Mail: elisabeth.santos(at)uni-ulm.de