Ammonium Metatungstate in Pigments and Ceramics

Ammonium metatungstate (AMT) holds unique application value in the field of pigments and ceramics. Its high solubility and thermal decomposition properties make it an ideal precursor for tungsten-based compounds, used in the preparation of high-performance ceramic colorants and functional ceramic materials. Specific applications include:

1. Ceramic Colorants: AMT can be thermally decomposed to form tungsten trioxide (WO₃), which, when mixed with a ceramic matrix, forms a stable tungsten-based colorant during high-temperature sintering (approximately 1000-1200°C). This imparts a distinctive yellow or green hue to ceramics, with excellent high-temperature resistance and chemical stability, making it suitable for decorative ceramics and high-end porcelain production.

2. Functional Ceramics: AMT can serve as a tungsten source to prepare tungstate-based ceramic materials (e.g., zinc tungstate, ZnWO₄), used in photocatalytic ceramics or high-temperature ceramic coatings. Its bandgap property (approximately 3.8 eV) enables ceramics to excel in photocatalytic degradation of pollutants, while the high hardness and corrosion resistance of tungstates enhance the mechanical properties of ceramics, making them suitable for industrial ceramic components.

3. Ceramic Additives: AMT can be used as an additive to improve the sintering performance of ceramics, regulating grain growth to enhance the density and strength of ceramics, thereby extending their service life. This is widely applied in fields such as ceramic cutting tools and ceramic bearings.