Hydrophobic aluminum-silicon aerogel composite material and preparation method thereof

The invention discloses a hydrophobic aluminum-silicon aerogel composite material and a preparation method thereof. The preparation method comprises the following steps: preparing silica sol and aluminum sol; compounding silicon-aluminum gel on a fiber support body based on the silica sol and the aluminum sol to obtain a composite silicon-aluminum gel fiber support body; placing the composite silicon-aluminum gel fiber support body in a first solvent for aging; carrying out supercritical drying on the aged composite silicon-aluminum gel fiber support body through a drying medium; the first solvent comprises ethyl alcohol and ethyl orthosilicate, and the volume ratio of ethyl orthosilicate to ethyl alcohol in the first solvent is 1: (5-20); hydrophobic modification of the aluminum-silicon aerogel composite material is achieved, and it is avoided that due to the fact that the aluminum-silicon aerogel composite material finished product and a hydrophobic modifier solution are combined for modification, part of w