Solid oxide fuel cells (SOFCs) are potentially the most efficient and cost-effective solution for the utilization of a wide variety of fuels beyond hydrogen. One of the chief obstacles to true fuel flexibility lies in anode deactivation by coking as well as a limited mechanistic understanding of coking and its prevention. Here we report Raman spectroscopic mapping and monitoring of carbon deposition on SOFC anode surfaces under both ex situ and in situ conditions. Carbon mapping was successfully demonstrated with a model Ni–YSZ electrode exposed to a CH4-containing atmosphere at high temperature (625 °C), while carbon deposition over time in a wet C3H8 atmosphere was directly monitored on a similar anode system as well as a BaO-modified system. This spectroscopic technique provides valuable insight into the mechanism of carbon deposition, which is vital in achieving rational design of carbon-tolerant anode materials.
