Английская Википедия:Indium(II) selenide

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Шаблон:Chembox Indium(II) selenide (InSe) is an inorganic compound composed of indium and selenium. It is a III-VI layered semiconductor. The solid has a structure consisting of two-dimensional layers bonded together only by van der Waals forces. Each layer has the atoms in the order Se-In-In-Se.[1]

Potential applications are for field effect transistors, optoelectronics, photovoltaic, non-linear optics, strain gauges,[1] and methanol gas sensors.[2]

Formation

Indium(II) selenide can be formed via a number of different methods. A method to make the bulk solid is the Bridgman/Stockbarger method, in which the elements indium and selenium are heated to over 900 °C in a sealed capsule, and then slowly cooled over about a month.[3] Another method is electrodeposition from a water solution of indium(I) sulfate and selenium dioxide.[4]

Properties

Файл:Indium (II) selenide polytopes.png
Diagram of polytopes of indium(II) selenide[3]

There are three polytopes or crystal forms. β, ε are hexagonal with unit cells spanning two layers. γ has rhombohedral crystal system, with the unit cell including four layers.[1]

β-Indium(II) selenide can be exfoliated into two-dimensional sheets using sticky tape. In a vacuum these form smooth layers. However when exposed to air, the layers become corrugated because of chemisorption of air molecules.[5] Exfoliation can also take place in isopropanol liquid.[6]

Indium (II) selenide is stable in ambient conditions of oxygen and water vapour, unlike many other semiconductors.[1]

polytope space group unit cell band gap eV
β P63/mmc a=4.005 c=16.660 Z=4 direct 1.28
γ R3m a=7.1286 Å, c=19.382 Å and Z=6 direct 1.29
ε PШаблон:Overlinem2 indirect 1.4

Doping

The properties of indium(II) selenide can be varied by way of altering the exact ratio of elements from 1:1, creating vacancies. It is hard to get an exact equality. The properties can be compensated by transition element doping. Other elements that can be included in small concentrations are boron,[7] silver,[8] and cadmium.[9]

References

Шаблон:Reflist

Шаблон:Indium compounds Шаблон:Selenides