Smart materials concept for SOFC anodes: Self-regenerating catalysts for efficient energy production from renewable fuels
Auf einen Blick
- Projektleiter/in : Dr. Andre Heel
- Projektteam : Dr. Dariusz Artur Burnat, Dr. Lorenz Holzer
- Projektvolumen : CHF 350'000
- Projektstatus : abgeschlossen
- Drittmittelgeber : SNF
Beschreibung
This interdisciplinary activity focuses on the evaluation of
multiphase microstructures for a novel smart catalyst concept in
the anode compartment of a fuel cell system. The drawback of
currently used state-of-the-art nickel cermet catalysts is the
general lack of microstructural stability against high temperature,
humidity, varying oxygen partial pressures. In addition, sulphur,
which is present in fossil but also in renewable fuels as addressed
in the joint project, immediately harm the Ni-catalyst and cause an
irreversible degradation, if exposed to sulphur for longer
times.
Microstructural and catalytic degradation becomes obvious by
aggregation, particle growth and loss of active surface area and
results in an increase of the polarisation resistance and lowers
the electrochemical activity. Furthermore, percolation of the
catalytic active nickel phase is limited and the electron pathways
are interrupted by particle growth, what again affects the ohmic
resistance of the fuel cell. To overcome these major degradation
effects a new material-based strategy is applied. An anode material
with an innovative “smart” effect is applied, where activity and
performance will be recovered by the material intrinsic
functionality to regenerate itself under an externally triggered
stimulus. A commonly harmful redox cycle with transient pO2
operating conditions is actively used to self regenerate the anode
catalyst. For this a fundamental understanding of the complex
reaction mechanism and the relationships between performance and
topological parameters on micro- and nanoscales is needed.
Sophisticated microstructure analysis (nanotomography, TEM, image
analysis) and numerical modelling and simulation will be combined
with detailed electrochemical investigations.