Fabrication of novel water glass-based monolithic aerogels with fibrous skeleton under alkaline for oil sorption and thermal evaporation

• Published in: Journal of non-crystalline solids 2023-07, Vol.611, p.122349, Article 122349
• Main Authors: Liu, Jun, He, Zhi-Wei, Bai, Ge, Zhu, Wen-Yao, Li, Xin, Xie, Heng-Xue, Wang, Hui, Chang, Meng-Jie, Yang, Jie, Wang, Yu-Qing, Luo, Zhen-Min
• Format: Article
• Language: English
• Subjects: Ambient pressure drying; Electrospun lectrospun SiO2 nanofibers; Monolithic aerogel; Solar thermal evaporation; Water glass
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/j.jnoncrysol.2023.122349

•Silica aerogels with novel core/shell fibrous skeleton structure were prepared.•The obtained aerogels exhibit good insulation at high temperature.•The hydrophobic aerogels could act as insulator for solar thermal evaporation. We presented the fabrication of novel water glass-based monolithic aerogel reinforced with the electrospun SiO2 nanofibers (SNFs) by one-step acid catalysis in alkaline condition under ambient pressure drying (APD). Compared with the powder-like water glass-based aerogel (WAG), integrated monolithic aerogel composited with nanofibers (FWAG) was successfully constructed featured with core/shell fibrous skeleton, low density, high porosity, hydrophobic surface and enhanced mechanical property. The obtained FWAG exhibits compressive elastic modulus of 0.13 MPa for FWAG-3 and a sorption capacity of 11.83 g−1 for CH2Cl2, as well as good insulator performance used at high temperature of ∼460 °C without obvious damage. The low density, hydrophobicity and excellent insulation property enable the FWAG to be applied as insulator for solar thermal evaporation with a water evaporation rate of 1.35 kg m−2h−1 and conversion efficiency up to 88.4% at one solar intensity to produce fresh water.