Tin(II) sulfide
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| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 446718715
| Reference = {{GESTIS|ZVG=4550|CAS=1314-95-0|Name=Tin(II) sulfide|Date=4/9/2007}}
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| IUPACName = Tin(II) sulfide
| OtherNames = Tin monosulfide
Herzenbergite
|Section1={{Chembox Identifiers
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo = 1314-95-0
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = J4580W867H
| EINECS = 215-248-7
| PubChem = 426379
| InChI = 1S/S.Sn
| SMILES = S=[Sn]
}}
|Section2={{Chembox Properties
| Formula = SnS
| MolarMass = 150.775 g/mol
| Appearance = dark brown solid
| Density = 5.22 g/cm3
| MeltingPtC = 882
| BoilingPt = about 1230 ˚C
| Solubility = Insoluble
}}
|Section3={{Chembox Structure
| CrystalStruct = GeS type (orthorhombic), oP8
| SpaceGroup = Pnma, No. 62
| Coordination = asymmetric 3-fold (strongly distorted octahedral)
| LattConst_a = 11.18 Å
| LattConst_b = 3.98 Å
}}
|Section7={{Chembox Hazards
| ExternalSDS =
| HPhrases =
| PPhrases =
| GHS_ref =
| MainHazards = Irritant
| NFPA-H =
| NFPA-F =
| NFPA-R =
| FlashPt =
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|Section8={{Chembox Related
| OtherAnions = Tin(II) oxide
Tin selenide
Tin telluride
| OtherCations = Carbon monosulfide
Silicon monosulfide
Germanium monosulfide
Lead(II) sulfide
| OtherCompounds = Tin(IV) sulfide
Tributyl tin sulfide
}}
}}
Tin(II) sulfide is an inorganic compound with the chemical formula is SnS. A black or brown solid, it occurs as the rare mineral herzenbergite (α-SnS).It is insoluble in water but dissolves with degradation in concentrated hydrochloric acid. Tin(II) sulfide is insoluble in ammonium sulfide.
Synthesis
The preparation of tin(II) sulfide has been extensively investigated, and the direct reaction of the elements is inefficient.{{cite journal|journal=Journal of Materials Chemistry|title=Atmospheric pressure chemical vapour deposition of tin(II) sulfide films on glass substrates from Bu{{su|p=n|b=3}}SnO2CCF3 with hydrogen sulfide|first1=Louise S.|last1=Price|first2=Ivan P.|last2=Parkin|first3=Mark N.|last3=Field|first4=Amanda M. E.|last4=Hardy|first5=Robin J. H.|last5=Clark|first6=Thomas G.|last6=Hibbert|first7=Kieran C.|last7=Molloy|orig-date=4 Oct 1999|date=27 Jan 2000|volume=10|issue=2 |page=527|doi=10.1039/a907939d |via=CiteSeerX}} Instead, molten potassium thiocyanate reliably reacts with stannic oxide to give SnS at 450 °C:{{cite book|title=Handbook of Preparative Inorganic Chemistry|volume=1|editor-first=Georg|editor-last=Brauer|translator-first=Reed F.|translator-last=Riley|year=1963|publisher=Academic|place=New York|lccn=63-14307|orig-date=1960|edition=2nd|first=M.|last=Baudler|chapter=Tin and lead|pages=739–740}}
:SnO2 + 2 KSCN → SnS + K2S + 2CO + N2
SnS also forms when aqueous solutions of tin(II) salts are treated with hydrogen sulfide. This conversion is a step in qualitative inorganic analysis.
At cryogenic temperatures, stannous chloride dissolves in liquid hydrogen sulfide. It then decomposes to the sulfide, but only slowly.{{cite journal|date=8 Jan 1925|title=A study of reactions in liquid hydrogen sulfide|first=G. N.|last=Quam|orig-date=5 Sept 1924|volume=47|pages=105–106|doi=10.1021/ja01678a014|journal=Journal of the American Chemical Society}} (Excerpted from a PhD thesis at 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".
Structure
At temperatures above 905 K, SnS undergoes a second order phase transition to β-SnS (space group: Cmcm, No. 63).{{Cite journal|title=Refinement of the structures of GeS, GeSe, SnS and SnSe : Zeitschrift für Kristallographie|journal=Zeitschrift für Kristallographie|volume=148|issue=3–4|pages=295–303|date=1978-01-01|language=en|doi=10.1524/zkri.1978.148.3-4.295|last1=Wiedemeier|first1=Heribert|last2=von Schnering|first2=Hans Georg|s2cid=53314748 }} A new polymorph of SnS exists based upon the cubic crystal system, known as π-SnS (space group: P213, No. 198).{{Cite journal |last=Miranti |first=Retno |last2=Septianto |first2=Ricky Dwi |last3=Kikitsu |first3=Tomoka |last4=Hashizume |first4=Daisuke |last5=Matsushita |first5=Nobuhiro |last6=Iwasa |first6=Yoshihiro |last7=Bisri |first7=Satria Zulkarnaen |date=2022-03-24 |title=π-SnS Colloidal Nanocrystals with Size-Dependent Band Gaps |url=https://pubs.acs.org/doi/10.1021/acs.jpcc.2c00266 |journal=The Journal of Physical Chemistry C |volume=126 |issue=11 |pages=5323–5332 |doi=10.1021/acs.jpcc.2c00266 |issn=1932-7447|url-access=subscription }}{{Cite journal|last1=Rabkin|first1=Alexander|last2=Samuha|first2=Shmuel|last3=Abutbul|first3=Ran E.|last4=Ezersky|first4=Vladimir|last5=Meshi|first5=Louisa|last6=Golan|first6=Yuval|date=2015-03-11|title=New Nanocrystalline Materials: A Previously Unknown Simple Cubic Phase in the SnS Binary System|journal=Nano Letters|volume=15|issue=3|pages=2174–2179|doi=10.1021/acs.nanolett.5b00209|pmid=25710674|bibcode=2015NanoL..15.2174R|issn=1530-6984}}{{Cite journal|last1=Abutbul|first1=R. E.|last2=Segev|first2=E.|last3=Zeiri|first3=L.|last4=Ezersky|first4=V.|last5=Makov|first5=G.|last6=Golan|first6=Y.|date=2016-01-12|title=Synthesis and properties of nanocrystalline π-SnS – a new cubic phase of tin sulphide|journal=RSC Advances|language=en|volume=6|issue=7|pages=5848–5855|doi=10.1039/c5ra23092f|bibcode=2016RSCAd...6.5848A|issn=2046-2069}}
Herzenbergite (α-SnS) can be exfoliated to form layered structure similar to that of black phosphorus, featuring 3-coordinate Sn and S centers.{{Greenwood&Earnshaw|page=1233}} Analogous to 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.{{cite journal | last1 = Brent | display-authors = etal | year = 2015 | title = Tin(II) Sulfide (SnS) Nanosheets by Liquid-Phase Exfoliation of Herzenbergite: IV–VI Main Group Two-Dimensional Atomic Crystals| journal = J. Am. Chem. Soc. | volume = 137 | issue = 39| pages = 12689–12696 | doi = 10.1021/jacs.5b08236 | pmid = 26352047| doi-access = free | bibcode = 2015JAChS.13712689B }}
Photovoltaic applications
Tin(II) sulfide has been evaluated as a candidate for 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.{{Cite journal|last1=Ginley|first1=D.|last2=Green|first2=M.A.|date=2008|title=Solar energy conversion towards 1 terawatt|journal=MRS Bulletin|volume=33|issue=4|pages=355–364|doi=10.1557/mrs2008.71|doi-access=free}} 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.{{Cite journal|last1=Andrade-Arvizu|first1=Jacob A.|last2=Courel-Piedrahita|first2=Maykel|last3=Vigil-Galán|first3=Osvaldo|date=2015-04-14|title=SnS-based thin film solar cells: perspectives over the last 25 years|journal=Journal of Materials Science: Materials in Electronics|language=en|volume=26|issue=7|pages=4541–4556|doi=10.1007/s10854-015-3050-z|s2cid=137524157|issn=0957-4522}} 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.{{Cite journal|last1=Nair|first1=P. K.|last2=Garcia-Angelmo|first2=A. R.|last3=Nair|first3=M. T. S.|date=2016-01-01|title=Cubic and orthorhombic SnS thin-film absorbers for tin sulfide solar cells|journal=Physica Status Solidi A|language=en|volume=213|issue=1|pages=170–177|doi=10.1002/pssa.201532426|bibcode=2016PSSAR.213..170N|s2cid=124780995 |issn=1862-6319}} Finally, Tin(II) sulfide is stable in both alkaline and acidic conditions.{{Cite journal|last1=Sato|first1=N.|last2=Ichimura|first2=E.|date=2003|title=Characterization of electrical properties of SnS thin films prepared by the electrochemical deposition method|journal=Proceedings of 3rd World Conference on Photovoltaic Energy Conversion|volume=A}} All aforementioned characteristics suggest tin(II) sulfide as an interesting material to be used as a solar cell absorber layer.
Power conversion efficiencies for tin(II) sulfide thin films in photovoltaic cells are less than 5%.{{Cite journal|last1=Jaramillo|first1=R.|last2=Steinmann|first2 =V.|last3=Yang|first3=C.|last4=Chakraborty|first4=R.|last5=Poindexter|first5=J. R.|date=2015|title=Making Record-efficiency SnS Solar Cells by Thermal Evaporation and Atomic Layer Deposition|journal= J. Vis. Exp.|issue=99|pages=e52705|doi=10.3791/52705|pmid=26067454|pmc=4542955|url=https://www.jove.com/video/52705/making-record-efficiency-sns-solar-cells-thermal-evaporation-atomic}} Barriers for use include a low open circuit voltage and an inability to realize many of the above properties due to challenges in fabrication.
References
{{Tin compounds}}
{{Sulfides}}