Sulfideselenium

Sulfideselenium refers to compounds that contain both sulfur and selenium in the same system, typically as mixed chalcogenides of a metal or as solid solutions between sulfide and selenide phases. The term is used for both naturally occurring minerals and synthetic materials in which sulfur and selenium occupy chalcogen sites within a lattice.

In many sulfideselenium systems, sulfur and selenium form a continuous solid solution, with compositions described by a formula such as M(S1−xSex) or (S,Se) units in the crystal structure. The exact arrangement and crystal structure depend on the specific metal cation and the overall composition, and different phases may coexist at certain temperatures and pressures. The chalcogen sites can be partially or fully occupied by S and Se, allowing tunability of physical properties through composition.

Occurrences include trace inorganic phases in ore deposits where sulfur and selenium are available, as well as a wide range of synthetic materials designed for electronic, optical, and energy applications. The ability to adjust the S/Se ratio enables control over properties such as band gap, electrical conductivity, and optical absorption, making sulfideselenium compounds of interest in photovoltaics, thermoelectrics, and photoelectrochemical devices.

Synthesis and characterization typically involve solid-state synthesis, high-temperature annealing, or chemical vapor transport to form homogeneous phases. Techniques such as X-ray diffraction, energy-dispersive spectroscopy, Raman spectroscopy, and UV–visible spectroscopy are used to determine structure, composition, and electronic properties. Safety considerations vary with the specific elements involved, particularly when transition metals or toxic chalcogenides are present.