The aerogel could be used to coat spacecrafts due to its resilience to certain conditions.
The aerogel comprises a network of tiny air pockets, with each pocket separated by two atomically thin layers of hexagonal boron nitride. It’s at least 99% space. To build the aerogel, Duan’s team used a graphene template coated with borazine, which forms crystalline boron nitride when heated. When the graphene template oxidises, this leaves a ‘double-pane’ boron nitride structure.
The basis of the newly developed aerogel is the 2D structure of graphene.
‘The key to the durability of our new ceramic aerogel is its unique architecture,’ says study co-author Xiangfeng Duan of the University of California, US.
‘The “double-pane” ceramic barrier makes it difficult for heat to transfer from one air bubble to another, or to spread through the material by traveling along the hexagonal boron nitride layers themselves, because that would require following long, circuitous routes.’
How does Aerogel technology work? Video: Outdoor Research
Unlike other ceramic aerogels, the material doesn’t become brittle under extreme conditions. The new aerogel withstood 500 cycles of rapid heating and cooling from -198°C to 900°C, as well as 1400°C for one week. A piece of the insulator shielded a flower held over a 500°C flame.