Facile fabrication of compressive aerogels with novel core/shell fibrous skeleton for oil sorption and thermal evaporation

Abstract

Due to the great size difference and poor interfacial compatibility, the traditional fiber reinforced aerogel composites mainly exist in form of particles deposited on the filled fibers with insufficient mechanical property. In this work, A novel compressive silica aerogel (SNAG) with electrospun SiO2 nanofibers (SNFs) as reinforcement was facilely established via a simple acid/base catalyzed two-step method under ambient pressure drying. The obtained SNAG is organized with unique fibrous core/shell skeletons to acquire excellent properties of low density, hydrophobicity, strong mechanical and effective insulation. The SNAG has a sorption capacity of 10.3 g g−1 for CH2Cl2 and can be repeatedly used through rapid compression and springback with a compressive ratio of 65%. The mechanical strength of the SNAG with 0.6 wt% SNFs can reach up to 0.23 MPa, which is 4.9 times higher than that of pure silica aerogel without addition of SNFs. Moreover, SNAG has been successfully employed as insulator for interfacial solar thermal evaporation with an evaporation rate of 1.31 kg m−2 h−1 to produce fresh water. It is believed that the obtained SNAG would be a prospective elastic aerogel for various applications and bring new insights into designing high-strengthen aerogels.