Ammonium metatungstate (AMT) is a significant tungstate compound, typically represented by the chemical formula (NH₄)₆H₂W₁₂O₄₀·nH₂O (where n is the number of water molecules of crystallization, commonly 1 or 2). Structurally, it belongs to the polyoxometalate family known as "tungsten clusters." Its core structure consists of 12 tungsten-oxygen octahedra connected through shared oxygen atoms, forming a cyclic or cage-like framework, with ammonium ions and protonated water molecules filling the gaps.

Barium tungsten electrodes are a cathode material widely used in electronic equipment and vacuum tubes such as displays, radars, and communications equipment. Its life is affected by a combination of factors.

The electronic work function of barium tungsten electrode is its core performance indicator, which directly affects its emission efficiency, operating temperature and life as a hot cathode. The factors affecting the electronic work function of barium tungsten electrode mainly include the following aspects:

Barium tungsten electrode is a cathode material widely used in vacuum electronic devices (such as electron guns and microwave tubes). Its microscopic defects have an important influence on the electron emission performance, thermal stability and mechanical strength of the electrode. The following are the main factors affecting the microscopic defects of barium tungsten electrodes: