Synchrotron Microtomography of Polymer Derived Macroporous SiOC Ceramics

Abstract

Porous ceramics have found immense applications in leading technological areas including porous burners, catalyst supports, and filtration media. It is extremely important to understand morphological features of highly porous ceramic bodies, and extract detailed quantitative information, including porosity, pore size distribution, interconnectivity, pore anisotropy, and sphericity. Synchrotron X‐ray microtomography has evolved as an excellent technique to acquire information on the complex three‐dimensional geometry and topology of reticulated structures. In this work, macroporous silicon oxycarbide ceramics are fabricated by positive replication of polyurethane sponge with the use of a preceramic polymer, and their topology has been studied by synchrotron X‐ray microtomography. Further, ceramic bodies have been prepared with progressive increase in the preceramic polymer concentration in the solution, and the ensuing change in the porous morphology of the structures have been studied. The results indicate the formation of excellent reticulated ceramics with 88–92% porosity, and with dense and uniform struts. The pore size distribution is uniform with very good sphericity and minimal anisotropy. The overall porosity indicates excellent interconnectivity with highly negative Euler numbers. The work presents a comprehensive analysis of reticulated ceramic bodies fabricated by preceramic polymer pyrolysis route.