Novel self-reinforcing ZrO2-SiO2 aerogels with high mechanical strength and ultralow thermal conductivity

Novel self-reinforcing ZrO2-SiO2 aerogels with high mechanical strength and ultralow thermal conductivity are fabricated by impregnating hydrolyzed ZrO2-SiO2 sol into wet gel matrix and drying. The ZrO2-SiO2 sol fills the macropores and defects of ZrO2-SiO2 aerogel matrix generating during the gelation process, which contributes to the improvement of the mechanical properties of the ZrO2-SiO2 aerogel matrix. The mechanical and thermal properties of the as-prepared ZrO2-SiO2 aerogel are investigated and discussed. The results show that the mechanical strength of the self-reinforcing aerogels obviously increases from 0.51 to 3.11 MPa with the increase of impregnation times, while the thermal conductivity of the aerogels slightly increases from 0.0235 to 0.0306 W m−1 K−1. The novel self-reinforcing ZrO2-SiO2 aerogel could have interesting applications in aerospace and energy because of its outstanding mechanical and thermal properties. © 2018 Elsevier Ltd and Techna Group S.r.l.