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On the stamen of a flower, there seemed to be a cloud of solidified “cloud”.
(Source: X Xu and X Duan)
This is actually a small piece of boron nitride aerogel sample. It is very light and has a density of only 1% of water.
Its microstructure under the scanning electron microscope is like this:
What is aerogel? You can imagine a three-dimensional network structure that “nets” the gel structure of water, and if you replace all the water in it with gas, it is an aerogel. Aerogels require special processes to prepare.
Aerogel materials are favored because they are very, very light and thermally insulating, and their application prospects include protecting aerospace equipment under extreme temperature conditions. However, many aerogels also have the problem that their mechanical properties are not stable enough, and they tend to become brittle during rapid temperature changes.
This time, the researchers made an aerogel with more stable mechanical properties. It can resist the high temperature of 1400°C for a week, or it can still survive a sudden temperature change (the temperature changes by 275°C in one second). Maintain the original mechanical properties. Although there are many follow-up studies that need to be done before it is actually put into application, I feel that these materials look really powerful.
Related research has recently been published in Science, and details can be found here: http://science.sciencemag.org/content/363/6428/723
Related reports: https://www.chemistryworld.com/news/light-as-air-ceramic-could-help-spacecraft-stay-cool/3010142.article