Indium(III) selenide is a compound of indium and selenium. It has potential for use in photovoltaic devices and has been the subject of extensive research. The two most common phases, α and β, have a layered structure, while γ has a "defect wurtzite structure." In all, five polymorphs are known: α, β, γ, δ, κ.[1] The α-β phase transition is accompanied by a change in electrical conductivity.[2] The band gap of γ-In2Se3 is approximately 1.9 eV.
Preparation
The method of production influences the polymorph generated. For example, thin films of pure γ-In2Se3 have been produced from trimethylindium (InMe3) and hydrogen selenide via MOCVD techniques.[3]
3 H2Se + 2 In(CH3)3 → In2Se3 + 6 CH4
A conventional route entails heating the elements in a seal-tube:[4]
^Crystal structure of κ-In2Se3. Jasinski, J.; Swider, W.; Washburn, J.; Liliental-Weber, Z.; Chaiken, A.; Nauka, K.; Gibson, G. A.; Yang, C. C. Applied Physics Letters, Volume 81, Issue 23, id. 4356 (2002) doi:10.1063/1.1526925
^Some Electrical and Optical Properties of In2Se3 D. Bidjin, S. Popovi, B. Elustka Physica Status Solidi A Volume 6, Issue 1, Pages 295 – 299 doi:10.1002/pssa.2210060133
^Growth of single-phase In2Se3 by using metal organic chemical vapor deposition with dual-source precursors Chang, K. J.; Lahn, S. M.; Chang, J. Y. Applied Physics Letters, Volume 89, Issue 18, id. 182118 (3 pages) (2006). doi:10.1063/1.2382742
^O. E. Donges (1963). "Indium Selenides and Tellurides". In G. Brauer (ed.). Handbook of Preparative Inorganic Chemistry, 2nd Ed. Vol. 2pages=865. NY, NY: Academic Press.