Effects of drying process on the microstructure and properties of biomass-derived porous carbon material

Abstract

In this study, a lightweight biomass-derived porous carbon materials with excellent mechanical and hydrophobic properties were prepared by a simple pyrolysis and carbonization method. The effects of different drying processes on the microstructure and properties of the porous carbon materials were investigated. The anisotropic porous carbon materials prepared via freeze-drying and vacuum drying exhibited low densities of 0.14 g/cm3 and 0.17 g/cm3, high water contact angles of 130.6 ± 2.6° and 111.5 ± 1.9°, and compression strengths of 0.32 MPa and 0.45 MPa. The surface tension increased during air drying, and the microstructure of the as-prepared porous carbon transformed from anisotropic to isotropic, displaying a higher density (0.22 g/cm3) and compression strength (0.72 MPa), but a lower water contact angle (90.4°). This work provides valuable guidance and inspiration for the design of lightweight structural-functional integrated porous carbon materials.