Hollow carbon fiber sponges from crude catkins: an ultralow cost absorbent for oils and organic solvents

In recent years, three-dimensional (3D) carbon-based frameworks have shown great potential as absorbents for oils or organic solvents, but the fabrication of carbon-based materials with low-cost and high-performance is still needed. In this paper, hollow carbon fiber sponges (HCFSs) have been synthesized through the pyrolysis of bulk crude catkins which are ultralow-cost, have a hollow structure and are a carbon-based fibrous material. Owing to their 3D framework and special structure, the HCFSs exhibited a high absorption capacity for organic solvents and oils (55-190 times their own weight) and excellent recyclability. Coupled with the convenient, economical and environmentally-friendly treatment process, HCFSs will be a promising candidate as a kind of absorbent for the removal of pollutants.