Dresden 2026 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 54: Nanostructured surfaces and thin films

O 54.5: Vortrag

Mittwoch, 11. März 2026, 11:30–11:45, HSZ/0201

Mesoporous Cobalt Ferrite Thin Film Oxygen Evolution Electrocatalysts: The Role of Fe-Content on Structure, Activity and Stability — •Ann-Kristin Stief, Barbara Gonzalez-Navarrete, Stefan Lauterbach, Jan Philipp Hofmann, and Marcus Einert — TU Darmstadt, Darmstadt, Germany

Cobalt Ferrite is a promising alkaline Oxygen Evolution Reaction (OER) catalyst to replace state-of-the-art but expensive Ir- and Ru-based acidic OER catalysts in green hydrogen production. Given the limited and contradictory literature on the optimum stoichiometry of Co3-xFexO4, we conducted a systematic stoichiometry study from x = 1.0 - 2.0 in increments of 0.2. To this end, mesoporous thin films were synthesized via dip-coating combined with soft-templating, using the commercially available polymer Pluronic F-127 for the first time. Electrochemical testing revealed that the x = 2.0 composition achieved the lowest iR-corrected overpotential (342 mV at 10 mA/cm²), the smallest Tafel slope, and the lowest charge transfer resistance. Structural characterization disclosed enhanced crystallinity, reduced grain size and higher degree of inversion upon Fe-enrichment. X-ray Photoelectron Spectroscopy (XPS) further indicated that Fe-rich precatalysts form higher surface concentrations of hydroxide or defective oxide. Together, these findings contribute to the understanding of composition-structure-activity relations of Cobalt Ferrite OER catalysts, thereby laying a foundation for tailoring their catalytic performance. This work was supported by BMFTR within SINATRA (TWOB, Award Nr. 033RC036).

Keywords: oxygen evolution reaction; electrocatalysis; mesoporous; spinel; cobalt ferrite