Tin(II) sulfide
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IUPAC name
Tin(II) sulfide
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Other names
Tin monosulfide
Herzenbergite | |
Identifiers | |
3D model (
JSmol ) |
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ECHA InfoCard
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100.013.863 |
EC Number |
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PubChem CID
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UNII | |
CompTox Dashboard (EPA)
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Properties | |
SnS | |
Molar mass | 150.775 g/mol |
Appearance | dark brown solid |
Density | 5.22 g/cm3 |
Melting point | 882 °C (1,620 °F; 1,155 K) |
Boiling point | about 1230 ˚C |
Insoluble | |
Structure | |
GeS type (orthorhombic), oP8 | |
Pnma, No. 62 | |
a = 11.18 Å, b = 3.98 Å, c = 4.32 Å[2]
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asymmetric 3-fold (strongly distorted octahedral) | |
Hazards | |
Occupational safety and health (OHS/OSH): | |
Main hazards
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Irritant |
Related compounds | |
Other anions
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Tin(II) oxide Tin selenide Tin telluride |
Other cations
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Carbon monosulfide Silicon monosulfide Germanium monosulfide Lead(II) sulfide |
Related compounds
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Tin(IV) sulfide Tributyl tin sulfide |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Tin(II) sulfide is a chemical compound of tin and sulfur. The chemical formula is SnS. Its natural occurrence concerns herzenbergite (α-SnS), a rare mineral. At elevated temperatures above 905 K, SnS undergoes a second order phase transition to β-SnS (space group: Cmcm, No. 63).[3] In recent years, it has become evident that a new polymorph of SnS exists based upon the cubic crystal system, known as π-SnS (space group: P213, No. 198).[4][5]
Synthesis
In principle, tin(II) sulfide can be prepared directly from the elements:
- Sn + S → SnS
However, the high-temperature reaction vaporizes sulfur. Consequently effecting the proper
At
Instead,
- SnO2 + 2 KSCN → SnS + K2S + 2CO + N2
Properties
Tin(II) sulfide is a dark brown or black solid, insoluble in water, but soluble in concentrated hydrochloric acid. Tin(II) sulfide is insoluble in (NH4)2S. It has a layer structure similar to that of black phosphorus.[9] As per black phosphorus, tin(II) sulfide can be ultrasonically exfoliated in liquids to produce atomically thin semiconducting SnS sheets that have a wider optical band gap (>1.5 eV) compared to the bulk crystal.[10]
Photovoltaic applications
Tin(II) sulfide is an interesting potential candidate for next generation thin-film solar cells. Currently, both cadmium telluride and CIGS (copper indium gallium selenide) are used as p-type absorber layers, but they are formulated from toxic, scarce constituents.[11] Tin(II) sulfide, by contrast, is formed from cheap, earth abundant elements, and is nontoxic. This material also has a high optical absorption coefficient, p-type conductivity, and a mid range direct band gap of 1.3-1.4 eV, required electronic properties for this type of absorber layer.[12] Based on the a detailed balance calculation using the material bandgap, the power conversion efficiency of a solar cell utilizing a tin(II) sulfide absorber layer could be as high as 32%, which is comparable to crystalline silicon.[13] Finally, Tin(II) sulfide is stable in both alkaline and acidic conditions.[14] All aforementioned characteristics suggest tin(II) sulfide as an interesting material to be used as a solar cell absorber layer.
At present, tin(II) sulfide thin films for use in photovoltaic cells are still in the research phase of development with power conversion efficiencies currently less than 5%.[15] Barriers for use include a low open circuit voltage and an inability to realize many of the above properties due to challenges in fabrication, but tin(II) sulfide still remains a promising material if these technical challenges are overcome.[13]
References
- ^ Record of Tin(II) sulfide in the GESTIS Substance Database of the Institute for Occupational Safety and Health, accessed on 4/9/2007.
- .
- S2CID 53314748.
- PMID 25710674.
- ISSN 2046-2069.
- ^ LCCN 63-14307.
- ^ doi:10.1039/a907939d – via CiteSeerX.
- Iowa State College.) "The chlorides of tin and phosphorus were all soluble, and slow decomposition resulted in the formation of the respective sulfides." See also Table 1, wherein "Stannous chloride" and "Stannic chloride" are both listed as "Soluble and reactive".
- ISBN 978-0-08-037941-8.
- PMID 26352047.
- .
- S2CID 137524157.
- ^ S2CID 124780995.
- ^ Sato, N.; Ichimura, E. (2003). "Characterization of electrical properties of SnS thin films prepared by the electrochemical deposition method". Proceedings of 3rd World Conference on Photovoltaic Energy Conversion. A.
- PMID 26067454.