Multifunctional magnetic superhydrophobic carbonaceous aerogel with micro/nano-scale hierarchical structures for environmental remediation and energy storage

Multifunctional magnetic superhydrophobic carbonaceous (MSC) aerogel with hierarchically porous structures is successfully prepared via carbonization process using disposable cotton balls followed by surface-coating of Fe₃O₄ particles and post hydrophobic-modified treatment with long-chain silanes. The developed MSC aerogel demonstrates ultralow density (<2 mg/cm³) and ultrahigh porosity (>99.9%), robust superhydrophobicity and superoleophilicity (θ_water = 160.5°, θ_oil = 0°, a rolling contact angle of 1.8°). The aerogel has excellent absorption capacity (61–113 g/g) for various oily liquids, and can be manipulated above the contaminated water under magnetism. More importantly, benefitting from its fire resistance and compressibility, the MSC aerogel can be recycled easily using distillation, squeezing and combustion, depending on the kinds of contaminants. Furthermore, this material can be a good candidate for supercapacitors. All these features make the material a versatile and comprehensive material for various applications in oil spill cleanup and energy storage.