Five analytical characteristics of silica airgel
Silica Aerogels is an excellent heat insulation performance nanoporous amorphous solid lightweight material, having a porosity as high as 80 to 99.8%, for the typical dimensions of 1-100 nm holes, specific surface area 200-1000m2 / g, and the density can be as low as 3kg / m3, the thermal conductivity at room temperature can be as low as 0.012W / (m • k). It is because of these characteristics make airgel material has a very broad application potential in thermal, acoustic, optical, microelectronics, particle detection aspects. Aproperties, insulating silica airgel has a very low thermal conductivity material, up to 0.013-0.016W / (m · K), below the static air (0.024W / (m · K)) in thermal conductivity coefficient, 2-3 orders of magnitude lower than the corresponding inorganic insulating material. Even at 800 ℃ high temperature of the coefficient of thermal conductivity was 0.043W / (m · K). It does not decompose at a high temperature, no harmful gas evolution, are environment-friendly materials. After the SiO2 aerogels with various heat resistant fiber composite can be made into various forms of insulating material . It can be widely used in industrial, construction, plumbing, automotive, aerospace and other fields. 2, since the sound insulation properties of aerogels of low sound velocity, it is an ideal acoustic delay or high temperature soundproofing material . Large acoustic impedance variable range of the material (103-107kg / m2 · s), is coupled acoustically resistive material is an ideal ultrasound probe. Preliminary results show that the density of around 300kg / m3 silica airgel as a coupling material can improve 30dB sound intensity, if silicon airgel has a density gradient, is expected to be higher sound intensity gain. 3, since the nonlinear optical properties of a quantum dot structure is formed within the silicon airgel nano network, a chemical vapor infiltration doped Si doped results indicate that the C60 and the solution process, the dopant is present in the form of nanocrystalline grains, and observed strong visible light emission, provides strong evidence for the emission quantum confinement effect of porous silicon. Silicon airgel structure and the nonlinear optical effects of C60, can be further developed new laser goggles. 4, with the catalytic properties of airgel filtered nanostructures may also be as a new gas filter, other materials with different pore size is uniform distribution of the material,High porosity, the material is a highly efficient gas filter. Since the material is extremely large specific surface and volume. Aerogels in the carrier side as a new catalyst or catalysts and also has broad application prospects. 5, the refractive index adjustability aerosilicon close L, and the ratio of coefficient of annihilation infrared and visible light up to 100 or more, can be effectively transmitted through the visible portion of the sunlight, and wherein the portion of the infrared light barrier , an ideal transparent insulation materials, and the use of solar energy in building energy conservation has been applied.