Silver(I) selenide is a chemical compound of silver and selenium. It is rarely found in the nature as mineral naumannite and is used in photography to produce selenium toning.
Silver selenide (Ag2Se) is a clear, hexagonal compound. It is the reaction product formed when selenium toning analog silver gelatine photo papers in photographic print toning.
The low - temperature phase of silver selenide is also a promising candidate for thermoelectric applications because of its relatively high Seebeck coefficient, low thermal conductivity, and high electrical conductivity.
Silver selenide has wide range of application in nonlinear optical devices , photo chargeable secondary batteries and ion-selective electrodes and in various other areas such as infra-red sensors and photolithographic layers