ZrC/C aerogel with high compressive strength by a carbothermic process

The ZrC/C aerogel is successfully prepared through copolymerization sols combined with carbothermal reduction method, using the ZrOC and phenol formaldehyde (PF) as the sols, and hexamethylenetetramine (HMTA) as cross-linker, respectively. The effects of heating treatment temperatures on physical and thermal properties of the aerogels are also investigated. XRD, SEM, and XPS measurements were adopted to characterize the morphology and microstructure of aerogels. Aerogels displayed low bulk density (0.262−0.379 g/cm³), relatively low thermal conductivity (0.0896−0.1064 W/m∙K), and high compressive strength (0.87–4.42 MPa). XRD results show that the aerogel is composed of ZrC and ZrO₂ phases at 1400 °C and ZrC at 1500 °C or even high temperature, respectively, indicating that phase transformation of ZrO₂ into ZrC. XPS results demonstrated that the element Zr, C, and O are based on Zr[sbnd]O[sbnd]C, Zr[sbnd]C, and Zr[sbnd]O valence band binding, respectively. ZrC/C aerogels with excellent physical and thermal properties may be used in high-temperature field soon.