A Facile Synthesis of a Three-Dimensional Flexible 3C-SiC Sponge and Its Wettability

Controllable synthesis of flexible ceramic whiskers at low cost remains a challenge despite their importance for many applications. In this work, a large-scale flexible SiC sponge has been successfully synthesized using carbon thermal reduction of gangue at 1500 degrees C for 2 h in an argon atmosphere by controlling the reaction atmosphere. The phase and microstructure investigated by XRD, SEM, TEM, and Raman spectroscopy revealed that the flexible SiC sponge was cubic single crystalline with a diameter of 100-500 nm and several millmeters in length. The good flexibility of SiC whiskers was attributed to their typical morphology of a straight line with a smooth surface. Besides this, another novel bamboo-like whisker consisting of twin transition and direct transformation also contributed to the flexibility of SiC whiskers. In addition, the sponge surface displays a good hydrophobicity. This provides SiC whiskers as a great promising candidate for the development of flexible illumination batteries and supercapacitors with high power and energy density.