High-temperature Raman spectroscopy of solid oxide fuel cell materials and processes

Area of Science:

• Materials Science
• Spectroscopy
• Electrochemistry

Background:

• High-temperature chemical processes are challenging to study due to limited in-situ experimental methods.
• Raman spectroscopy offers a non-invasive approach to probe species and material properties at elevated temperatures.
• Yttria-stabilized zirconia (YSZ) and species like Ni/NiO and graphite are crucial in solid oxide fuel cell (SOFC) chemistry.

Discussion:

• Raman spectroscopy successfully identified in-situ and non-invasively material property changes and molecular species formation/disappearance at 715°C.
• The technique tracked reversible oxidation/reduction kinetics of Ni/NiO and the consumption rate of in-situ formed graphite.
• YSZ's Raman active phonon mode exhibited temperature-dependent shifts correlating with lattice expansion, enabling thermal gradient diagnostics.

Key Insights:

• Raman spectroscopy is effective for in-situ analysis of chemical and material processes at high temperatures.
• The method can monitor dynamic changes in SOFC-relevant materials and species.
• Temperature-dependent shifts in YSZ's phonon modes serve as an internal thermometer for high-temperature systems.

Outlook:

• In-situ Raman spectroscopy is a powerful tool for understanding operational SOFCs.
• This technique can provide direct insights into complex electrochemical environments.
• Further application of Raman spectroscopy can advance the development of high-temperature energy systems.