Processing of porous ceramic structures for efficient mass transport
Ability to manufacture ceramic structures with ef cient porosity and at the same time, suf- cient mechanical robustness is important for a broad range of applications, such as; catalyst supports, lters, fuel cells, electrolysis electrodes, membrane reactors, CO2 capture and ue gas puri cation.
The use of sacri cial pore formers, one of the most commonly used methods to generate porous ceramic structures, delivers structures with random and inef cient porosity. There- fore, alternative processing routes capable of delivering effective porosity are under high demand.
Three approaches capable of accomplishing high mass transport ceramic structures will be discussed: use of non-combustible pore formers, use of ice templating (freeze casting) and additive manufacturing. Non-combustible pore former route is based on porosity formation after nal sintering step via reduction or mild leaching and results in a highly-interconnected porosity. Ice templating route is based on porosity creation through generation and sublima- tion of ice crystals and is capable of generating ceramic scaffolds with desired pore size and orientation. Additive manufacturing technique is based on generation of complex large scale ceramic bodies with programmed porosity channels. All these approaches proved to deliver so called ef cient porosity at different scales. Both ice templating and additive manufactur- ing routes can be further tuned to generate structures with hierarchical porosity distribution.
The talk will be illustrated with some practical examples, where the challenges related to fabrication of desired microstructures via these approaches will be presented.