Seminar - 2D (Metal-) Organic Networks as Electrocatalysts for Energy Conversion
Dr. Rico GUTZLER
4. 12. 2018 12:30 - 13:30
CEITEC Purkyňova 123, seminar room S2.02
On the route towards a rational design of catalyst materials, structuring the catalyst surface with atomic precision is a major mile stone. To this end, self-assembly strategies can be used to place organic molecules and single metal centers on well-defined positions.
(Metal-)organic supramolecular chemistry on surfaces has matured to a point where its underlying growth mechanisms are well understood and structures of defined coordination environments of metal atoms can be synthesized in a controlled and reproducible procedure. With surface-confined molecular self-assembly, scientists have a tool box at hand which can be used to prepare structures with desired properties, as for example a defined oxidation number and spin state of the transition metal atoms within the organic matrix. Alternatively, a catalyst surface can be patterned by all-organic polymers, thus tuning the interaction of reactants with the catalyst. These properties render organic networks with or without embedded metal centers interesting candidates for electrocatalytic applications.
Herein, we focus on the structural and chemical integrity of a bimetallic-organic single layer network on Au(111) during oxygen evolution and oxygen reduction reaction (OER & ORR). Depending on the reaction direction, we observe different stability of the network, with a rapid decomposition of the network during OER and conversion into oxide structures.These findings promoted us to extend our studies to the fate of intially well-defined metal oxide islands on Au(111) during OER and the hydrogen evolution reaction (HER). In the last part, we show how structuring a Au(111) surface with a porous single-layer 2D polymer can increase HER activity.