Gallium(III) sulfide, Ga
2S
3, is a compound of
sulfur and
gallium, that is a semiconductor that has applications in
electronics
The field of electronics is a branch of physics and electrical engineering that deals with the emission, behaviour and effects of electrons using electronic devices. Electronics uses active devices to control electron flow by amplification ...
and
photonics
Photonics is a branch of optics that involves the application of generation, detection, and manipulation of light in form of photons through emission, transmission, modulation, signal processing, switching, amplification, and sensing. Though ...
.
Structure
There are four
polymorphs, α (hexagonal), α' (monoclinic), β(hexagonal) and γ(cubic). The alpha form is yellow. The crystal structures are related to those of
ZnS ZNS or ZnS may refer to:
* Zinc sulfide or zinc sulphide (ZnS), a chemical compound
* ZNS-TV, a national radio and TV broadcaster operated by the state-owned Broadcasting Corporation of The Bahamas
** ZNS-1
ZNS-1 (branded as ''Radio Bahamas'') i ...
with gallium in tetrahedral positions.
[The Chemistry of Aluminium, Gallium, Indium and Thallium, Anthony John Downs, 1993, , ] The alpha and beta forms are isostructural with their aluminium analogues.
The similarity in crystal form of gamma- with
sphalerite (zinc blende),
ZnS ZNS or ZnS may refer to:
* Zinc sulfide or zinc sulphide (ZnS), a chemical compound
* ZNS-TV, a national radio and TV broadcaster operated by the state-owned Broadcasting Corporation of The Bahamas
** ZNS-1
ZNS-1 (branded as ''Radio Bahamas'') i ...
is believed to explain the enrichment of gallium in
sphalerite ores.
Preparation and chemical properties
Ga
2S
3 can prepared by reacting the elements at high temperature or as a white solid by heating Ga in a stream of
H2S at high temperature (950 °C).
It may also prepared by a solid state reaction of
GaCl3 and
Na2S.
The method of production can determine the polymorphic form produced, the reaction of
Ga(OH)3 with
H2S at different temperatures is reported to produce a different polymorph depending on the temperature, α- 1020 K, β- 820 K and γ- above 873 K
Ga
2S
3 decomposes at high temperature forming the
non-stoichiometric
In chemistry, non-stoichiometric compounds are chemical compounds, almost always solid inorganic compounds, having elemental composition whose proportions cannot be represented by a ratio of small natural numbers (i.e. an empirical formula); m ...
sulfide, Ga
4S
x (4.8 < x < 5.2).
Ga
2S
3 dissolves in aqueous acids and decomposes slowly in moist air forming
H2S.
Ga
2S
3 dissolves in aqueous solutions of
potassium sulfide, K
2S to form K
8Ga
4S
10 containing the (Ga
4S
10)
8− anion which has an
adamantane
Adamantane is an organic compound with a formula C10H16 or, more descriptively, (CH)4(CH2)6. Adamantane molecules can be described as the fusion of three cyclohexane rings. The molecule is both rigid and virtually stress-free. Adamantane is the ...
,
molecular P4O10 structure.
Ternary sulfides M
IGaS
2, M
IIGa
2S
4 and M
IIIGaS
3 respectively have been of interest due to their unusual electrical properties and some of these can be prepared by reactions of Ga
2S
3 with metal sulfides e.g. CdGa
2S
4:-
:Ga
2S
3 +
CdS
The compact disc (CD) is a digital optical disc data storage format that was co-developed by Philips and Sony to store and play digital audio recordings. In August 1982, the first compact disc was manufactured. It was then released in Octo ...
→ CdGa
2S
4
Although by itself Ga
2S
3 is not a glass former it can be reacted with rare earth sulfides to form glasses e.g. the reaction with lanthanum sulfide, La
2S
3, forms
gallium lanthanum sulfide glass which has interesting optical properties and is a semiconductor.
[Semiconducting Chalcogenide Glass III: Applications of Chalcogenide Glasses, Robert Fairman, Boris Ushkov, Elsevier, 2004, (ebook), ]
References
{{Sulfides
Sulfides
Gallium compounds