Recently, in the laboratory, we conducted an experiment with aerogel that defied common sense. We poured soy sauce, milk tea, and ink onto it, and the result was surprisingly consistent: all the liquids rolled off, leaving the surface spotlessly clean, not a drop remaining.
The principle behind this phenomenon actually involves two layers of defense mechanisms.
The first layer is physical water repellency. The surface of the aerogel is covered with nanoscale protrusions, like a bed of nails, preventing water droplets from "lying flat".
The second layer is chemical indifference. The surface is modified with fluorides, making it even more "heartless" than the coating of a non-stick pan.
How strong is this superhydrophobic effect? Its contact angle can reach over 170 degrees. The moment the water droplets bounce off, it feels like stepping on a trampoline. In contrast, the contact angle of a lotus leaf is approximately 160 degrees, and the water droplets roll off slowly.
The applications of this magical aerogel go far beyond this.
In the field of outdoor equipment, some brands have already used it to coat raincoats. Even in heavy rain, the inner layer of the coat remains dry, which is truly waterproof.
In the field of offshore oil storage, the superhydrophobic property of the aerogel on the surface of the float can prevent crude oil from adhering, reducing the risk of leakage by 90%.
In the field of architecture, the glass curtain wall of the Burj Khalifa in Dubai is coated with aerogel. After a sandstorm, the rain can automatically clean it, making the cleaning staff very happy.
There are even more imaginative ideas, such as using it to make self-cleaning cars. On rainy days, going out is equivalent to automatic car washing, and the mud will fall off by itself; or making anti-fouling tableware, where the soup of the snail rice noodles can slide away in an instant, and dishwashers might even become unemployed.
The most astonishing thing is that the hydrophobicity of aerogel is so strong that it can "walk on water". One gram of material can carry a one-kilogram weight and float on the water surface.
However, some netizens have raised a realistic concern: "Waterproof is good, but can the price of aerogel also 'keep away' from me?"