Biomorphic porous ceramics obtained by infiltration of a Si-based preceramic polymer into poplar wood templates

Abstract

In this work, a comprehensive and detailed study about the development and characterization of biomorphic porous SiOC/SiC/Si3N4/C-based ceramics was addressed with an integral approach. The materials were obtained using a novel processing route involving the infiltration of a Si-based preceramic polymer into activated poplar wood templates, thermal curing and N2 pyrolysis. The physical, structural, microstructural, and textural properties mostly depended on the degree of infiltration reached and the pyrolysis temperature used. All the developed porous microstructures exhibited the poplar wood´s features. It is worth noting the development of macropores with confined Si3N4 crystals, and particularly in the samples pyrolyzed at 1500 and 1600 °C, one-dimensional Si-based nanostructures, and micro- and mesopores located in cavity walls and within arrangements of the one-dimensional structures, mainly in the materials pyrolyzed at 1400 and 1500 °C. The last materials presented the highest specific surface area values, thus making them potential candidates in catalysts.