Solid Oxide Cells for CO2 Recycling: 3D Electrode Microstructure Reconstruction using FIB-SEM

Start date: September 2017

Recycling carbon dioxide to form fuel gives the potential for a carbon neutral fuel cycle – reducing net CO2 emissions and reducing dependence on fossil fuels. Electrolysis using a solid oxide cell has been shown to be an effective way of co-reducing CO2 and H2O to form syngas, the precursor for synthetic fuels. Whilst much research has been done on co-electrolysis in recent years, there still remain significant gaps in the understanding of fundamental reaction mechanisms and operating regimes to reduce degradation and extend lifetime. These need to be answered in order for co-electrolysis to reach large scale commercialisation. The effectiveness of reactant conversion to syngas in a solid oxide electrolyser is related to a number of factors including materials, operating conditions, and microstructure.

The goal of this project is to investigate the relationship between electrode pore microstructure and the resulting density of active sites for electrochemical conversion to cell performance. This will be achieved by varying the pore microstructure of the active electrodes via the use of novel pore-formers and infiltrating the resulting structure using a sol-gel method to produce nano-particles – forming the electrochemically active regions needed for successful syngas production. Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) will be used to serial section porous electrode structures and a protocol for completing image segmentation and analysis using methods such as thresholding and watershed will be investigated.