High-temperature electrochemistry and functionalized surfaces

Our research group tackles open material science problems related to the development of components for printed electronics, solid-state batteries, molten-salt electrolysis, and molten-carbonate fuel cells. This includes:

• Co-processing/sintering of materials with very different thermal stability: printed metallic structures on flexible thermally sensitive substrates, components of solid-state batteries (electrolytes, composite cathodes, half cells)
• Densification of ceramic and glass materials at temperatures < 400°C and high pressure
• Increasing corrosion stability of ceramic and metallic materials in molten salts at temperatures from 600°C to 1000°C (reducing and oxidizing gas compositions)

Innovative material processing methods such as high-power diode laser array and cold sintering are comprising the core research expertise of our group. They enable development and preparation of materials and components with previously non-existing combination of physical properties. It is complemented by longstanding experience in preparation and characterization of materials suitable for applications in molten salts (carbonates, chlorides).

Services offered
 

• Cold sintering processing (T<400°C) of ceramics. Demonstrated feasibility for:
  • Solid-state battery materials (solid electrolytes, composite cathodes)
  • Glass-containing materials
  • Complex oxides (CaRuO₃)
• High-power diode laser array processing of wet-chemically deposited materials:
  • Realization of structures with high electrical conductivity based upon noble (Ag, Au, Pt, PtRh) and non-noble (Cu, Ni, Fe-Ni, Mo, Bi) metals on rigid and flexible substrates
  • Surface sealing of ceramic matrix composites
• Development of customer-specific printed flexible magnetic field sensors and their arrays based on magneto-resistive effects
• Development of materials (e.g. LiAlO₂, CaRuO₃) with defined phase composition and specific surface for applications at high temperatures in molten salts
• Testing materials for molten-carbonate fuel cells and molten-salt electrolysis.

Special technical equipment
 

• High-power diode laser array with line-shaped optical field: continuous wave operation, millisecond time scale
• System for high-precision measurement of resistance at different temperatures (-100°C to 600°C) and in magnetic field (up to 500 mT): Kelvin, Van-der-Pauw and Hall-Effect measurements possible (RTM-1, Tensormeter Instruments)
• Thin-film x-ray fluorescence (XRF) spectroscopy facility: thickness and composition mapping
• High-temperature electrochemical impedance spectroscopy: characterization of electrochemical sensors, proton conductors and molten-carbonate fuel cells (temperatures up to 1000°C, reducing or oxidizing gas mixtures with addition of CO₂ and water vapor)
• Furnaces for calcining of powder materials (reducing and oxidizing gas ambience)