Electrochemistry at Metallic Surfaces
The performance, durability and sustainability of structural metals and alloys, as applied in diverse technologies from microelectronics, sensing technologies, medical implants to transportation and large infrastructures, critically depend on the electrochemical interaction of their functional surfaces with the operating environment, which is co-determined by the passivation behavior (i.e. nm-thick oxide formation) of compositional and structural heterogeneities at the metallic surface. We develop custom-tailored technological solutions for the pre-oxidation, anodizing and (electro)chemical surface functionalization of metals, alloys and multimaterials components. Our surface treatments are sustainable by avoiding the use of toxic chemicals and lowering energy consumption, while at the same time providing efficient, reliable and durable service conditions in harsh environments.
OUR RESEARCH
The trends in e.g. advanced manufacturing, digitalization, E-mobility and the aging society push the development of novel light-weight alloys, high-strength steels, nanocomposites and personalized medical implants by advanced manufacturing methods, such as 3-D printing. These materials are often multiphase and nanostructured and therefore highly heterogeneous in their composition and structure, especially towards their surfaces. Related to these technologies, surface functionalization by e.g. coatings, laser structuring, machining and/or (electro)chemical treatment has become an ever-important step for tuning specific surface properties, such as biocompatibility (e.g. cell interaction), wetting, friction, adhesion and/or bond-specific surface reactivities.
Accordingly, our research focusses at:
- The reactivity of the functionalized surfaces in different harsh environments (e.g. humid polluted atmospheres, aqueous electrolytic solutions, complex physiological media), as investigated by a broad spectrum of analytical techniques (e.g. electrochemical impedance spectroscopy, quartz crystal nanogravimetry, photo-electrochemistry, local electrochemistry, HAXPES/XPS, AES, environmental AFM/SKPFM, solid-state and solution analytics, SEM/EDS, ellipsometry and Raman spectroscopy).
- Development of novel surface functionalization strategies to stimulate in-vivo implant-cell interactions, prevent toxic ion leaching, control the dissolution kinetics. To this end, the in-vitro electrochemical stability and biocompatibility of heterogeneous metallic implant materials are investigated under static and dynamic loading conditions with special emphasis on passivation, corrosion product formation, galvanic coupling and active dissolution kinetics (i.e. metal-ion leaching) in confined spaces (i.e. in artificial crevices).
- Interaction of surficial oxides at their solid-liquid interfaces with biology (SNF Ambizione, led by M. Cihova).
- Development of novel concepts for sustainability/circularity through electrochemical recycling strategies.
