Flexible, versatility and superhydrophobic biomass carbon aerogels derived from corn bracts for efficient oil/water separation

Abstract Resource utilization of corn bracts is essential from the viewpoint of environmental protection and sustainable development due to the adverse impacts emanating from potential fire hazards and environmental pollution of agricultural wastes. Herein, we present a versatile, convenient and green process to fabricate porous superhydrophobic biomass carbon (BC) aerogel by using corn bracts as main raw material, as well as its application in selective oil/water separation. During this process, the flexible and ultralight BC aerogel was obtained by corn bracts as main raw via simple alkalization, bleaching, freeze drying and carbonization. The resultant BC aerogels that constituted by interconnected corn bracts-based carbon fibers exhibit a three-dimensional hierarchical porous structure in microscale. The characterization results indicated that the obtained BC aerogels exhibit large specific surface areas (675.85 m 2 /g), mesoporous structures (3.92 nm on average), and superhydrophobicity (water contact angle > 150°). The BC aerogels can absorb a broad variety of oils and organic solvents with high selectivity and excellent absorption capacities (77.67–143.63 g/g). At the same time, the BC aerogels have excellent oil recoverability and reusability properties after ten recycles, making them particularly attractive materials to treat oily wastewater. The current research can offer a green approach to fabricate superhydrophobic BC aerogels with well-defined 3D network structure for efficient oil/water separation, and the fabrication of BC aerogels can be extended for the preparation of other functional aerogels by low-cost agricultural wastes for various applications.