Under the condition of ensuring the porous structure, how to correctly assemble crystalline ceramic nanomaterials into closed-cell foam or open-cell nano-lattices without affecting its thermal conductivity, porosity, mechanical integrity, etc. has always been a concern for scientific researchers. . Traditionally, porous materials are designed by controlling the pore topology and geometry, such as customizing the porous structure according to porosity, pore size, shape, interconnection and distribution of pores, etc. However, the thermal conductivity of the material will vary greatly. So, how to properly design the microstructure of the material is really mind-blowing. Due to the large capillary energy, nanostructures are very unstable at high temperatures, so the preparation of nanomaterials that can withstand temperatures up to 1000°C is still a blank.
In order to make up for this vacancy, Wang Changan of Tsinghua University, An Linan of the University of Florida, and Li Juqiang of the Massachusetts Institute of Technology joined forces to use refractory ceramics with high temperature stability as raw materials, and proposed a synthesis of ceramic materials with hollow-grain nanostructures. With the new method, the material has super-insulation performance in a wide temperature range (25℃-1400℃). The research was published on "Materials Today" with the title "Hollow-grained "Voronoi foam" ceramics with high strength and thermal superinsulation up to 1400 ℃".