Aerogel is a kind of ultra-light solid material with a unique nano-porous structure. Due to its characteristics such as extremely light weight, high porosity, low thermal conductivity and high specific surface area, it has shown revolutionary application potential in multiple industries. 
At present, aerogels have been applied in aerospace, industrial building energy conservation, new energy technology, environmental protection, electronic optical devices, medical and biological engineering, military security protection, scientific research, extreme environments, the automotive industry, as well as in clothing and consumer goods in daily life. 
So what specific properties do aerogels possess that enable them to have such wide applications? And what is the preparation method for aerogels? As the manufacturer of aerogel production equipment, the editor of Modern Precision Machinery will introduce aerogels to everyone. 
Aerogel is a material synthesized through the sol-gel method and processed using supercritical drying technology to remove the liquid components from the gel, while retaining its three-dimensional nano-porous structure. The gas content in its structure can reach over 99%, and its density is extremely low (as low as 0.001 g/cm³), earning it the nickname "solid smoke". 
Main components 
Silica-based aerogel: The most common type, with a silica framework, featuring excellent thermal insulation properties. 
Carbon-based aerogels: composed of materials such as graphene or carbon nanotubes, they have excellent electrical conductivity and are used for energy storage. 
Polymer-based: Good flexibility, suitable for flexible devices. 
Other types: such as metal oxides, biomass-based, etc., expand diversified applications. 
Characteristics

Super lightweight and low density: The density is close to that of air, and it can withstand pressures thousands of times its own weight. 
High specific surface area: Can reach over 1000 m²/g, with strong adsorption capacity. 
Extremely low thermal conductivity (0.013 - 0.025 W/(m·K)): Superior to traditional insulation materials. 
Multifunctionality: Conductivity (carbon-based), light transmissivity (transparent silicon-based), high temperature resistance (some types can withstand up to 1200℃). 
Preparation process 
Solv-gel reaction: The precursor (such as silicate) undergoes hydrolysis to form a wet gel. 
2. Aging and solvent replacement: Strengthen the framework structure and replace the pore-occupying liquid with a solvent of low surface tension. 
3. Supercritical drying: Under high pressure and high temperature, the solvent is transformed into a supercritical fluid to prevent structural collapse. 
4. Alternative technology: Atmospheric drying (low cost but the structure may shrink). 
Application fields 
Heat insulation: Spacecraft (such as Mars rovers), building insulation, outdoor equipment. 
Environmental protection: Oil pollution adsorption (carbon-based), pollutant filtration. 
Energy: Supercapacitors, battery electrodes (carbon-based), catalyst carriers. 
Research and Medicine: Particle Detectors, Drug Sustained Release. 
Challenges and Prospects 
Brittleness: Enhances mechanical strength through the use of composite fibers or polymers. 
High cost: Developing atmospheric drying technology can reduce costs. 
Emerging applications: Flexible electronics, acoustic metamaterials, 3D printing. 
Historical Background 
1931: Samuel Kistler first produced silica aerogel. 
In the 1990s and beyond: NASA promoted the application of these materials in space exploration and developed various new types of aerogels. 
Due to its revolutionary properties, aerogel is moving from the laboratory to industrial and daily life applications. It holds great potential in the fields of green energy and high technology in the future.