Ammonium metatungstate (AMT) plays a significant role in the field of thermal insulation films, as it serves as an ideal precursor for tungsten-based nanomaterials, imparting excellent infrared-blocking performance to the films. Specific applications include:

1. Building Insulation Films: AMT can be used to prepare tungsten oxide (WO?) nanoparticles through sol-gel or hydrothermal methods, which are then incorporated into polyester (PET) base films to create thermal insulation films. WO? nanoparticles exhibit high infrared absorption capacity (blocking 80%-90% of near-infrared light, wavelength 780-2500 nm) while maintaining a high visible light transmittance (approximately 70%), effectively reducing indoor temperatures. This makes them suitable for building glass window films, offering significant energy-saving benefits.

2. Automotive Insulation Films: WO? nanomaterials prepared from AMT can be used in automotive window films. Their excellent infrared-blocking performance reduces heat buildup inside the vehicle, enhancing passenger comfort while protecting the interior from UV-induced aging. Additionally, the bandgap of WO? (2.6-3.0 eV) provides the film with electrochromic functionality, allowing transparency to be adjusted via voltage, meeting the demands of smart thermal insulation.

3. Agricultural Insulation Films: Tungsten-based insulation films prepared from AMT can be used in agricultural greenhouses, blocking infrared rays to lower internal temperatures while allowing visible light to pass through, promoting photosynthesis and increasing crop yields. This is suitable for modern agricultural greenhouse covering materials.