Indium(III) sulfide (Indium sesquisulfide, Indium sulfide (2:3), Indium (3+) sulfide) is the inorganic compound with the formula In2S3.

Indium(III) sulfide
Names
Other names
Indium sesquisulfide
Diindium trisulfide
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.031.571 Edit this at Wikidata
UNII
  • InChI=1S/2In.3S checkY
    Key: ZOMNDSJRWSNDFL-UHFFFAOYSA-N checkY
  • InChI=1/2In.3S/rIn2S3/c3-1-5-2-4
    Key: ZOMNDSJRWSNDFL-YYMIQOPKAJ
  • S=[In]S[In]=S
Properties
In2S3
Molar mass 325.82 g·mol−1
Appearance red powder
Density 4.90 g cm−3, solid
Melting point 1,050 °C (1,920 °F; 1,320 K)
insoluble
Hazards
GHS labelling:[1]
GHS07: Exclamation mark
Warning
H302+H332, H315, H319, H335
P280, P301+P330+P331, P302+P352, P304+P340, P312, P332+P313, P337+P313
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 4: Will rapidly or completely vaporize at normal atmospheric pressure and temperature, or is readily dispersed in air and will burn readily. Flash point below 23 °C (73 °F). E.g. propaneInstability 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazards (white): no code
3
4
2
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

It has a "rotten egg" odor characteristic of sulfur compounds, and produces hydrogen sulfide gas when reacted with mineral acids.[2]

Three different structures ("polymorphs") are known: yellow, α-In2S3 has a defect cubic structure, red β-In2S3 has a defect spinel, tetragonal, structure, and γ-In2S3 has a layered structure. The red, β, form is considered to be the most stable form at room temperature, although the yellow form may be present depending on the method of production. In2S3 is attacked by acids and by sulfide. It is slightly soluble in Na2S.[3]

Indium sulfide was the first indium compound ever described, being reported in 1863.[4] Reich and Richter determined the existence of indium as a new element from the sulfide precipitate.

Structure and properties

edit

In2S3 features tetrahedral In(III) centers linked to four sulfido ligands.

α-In2S3 has a defect cubic structure. The polymorph undergoes a phase transition at 420 °C and converts to the spinel structure of β-In2S3. Another phase transition at 740 °C produces the layered γ-In2S3 polymorph.[5]

β-In2S3 has a defect spinel structure. The sulfide anions are closely packed in layers, with octahedrally-coordinated In(III) cations present within the layers, and tetrahedrally-coordinated In(III) cations between them. A portion of the tetrahedral interstices are vacant, which leads to the defects in the spinel.[6]

β-In2S3 has two subtypes. In the T-In2S3 subtype, the tetragonally-coordinated vacancies are in an ordered arrangement, whereas the vacancies in C-In2S3 are disordered. The disordered subtype of β-In2S3 shows activity for photocatalytic H2 production with a noble metal cocatalyst, but the ordered subtype does not.[7]

β-In2S3 is an N-type semiconductor with an optical band gap of 2.1 eV. It has been proposed to replace the hazardous cadmium sulfide, CdS, as a buffer layer in solar cells,[8] and as an additional semiconductor to increase the performance of TiO2-based photovoltaics.[7]

The unstable γ-In2S3 polymorph has a layered structure.

Production

edit

Indium sulfide is usually prepared by direct combination of the elements.

Production from volatile complexes of indium and sulfur, for example dithiocarbamates (e.g. Et2InIIIS2CNEt2), has been explored for vapor deposition techniques.[9]

Thin films of the beta complex can be grown by chemical spray pyrolysis. Solutions of In(III) salts and organic sulfur compounds (often thiourea) are sprayed onto preheated glass plates, where the chemicals react to form thin films of indium sulfide.[10] Changing the temperature at which the chemicals are deposited and the In:S ratio can affect the optical band gap of the film.[11]

Single-walled indium sulfide nanotubes can be formed in the laboratory, by the use of two solvents (one in which the compound dissolves poorly and one in which it dissolves well). There is partial replacement of the sulfido ligands with O2−, and the compound forms thin nanocoils, which self-assemble into arrays of nanotubes with diameters on the order of 10 nm, and walls approximately 0.6 nm thick. The process mimics protein crystallization.[12]

 
Indium(III) sulfide nanocoils (a), nanotubes (b), and their ordered arrays (d-f). Scale bars: a,d,e,f - 50 nm; b - 100 nm.[12]

Safety

edit

The β-In2S3 polymorph, in powdered form, can irritate eyes, skin and respiratory organs. It is toxic if swallowed, but can be handled safely under conventional laboratory conditions. It should be handled with gloves, and care should be taken to keep from inhaling the compound, and to keep it from contact with the eyes.[13]

Applications

edit

Photovoltaic and Photocatalytic

edit

There is considerable interest in using In2S3 to replace the semiconductor CdS (cadmium sulfide) in photoelectronic devices. β-In2S3 has a tunable band gap, which makes it attractive for photovoltaic applications,[11] and it shows promise when used in conjunction with TiO2 in solar panels, indicating that it could replace CdS in that application as well.[7] Cadmium sulfide is toxic and must be deposited with a chemical bath,[14] but indium(III) sulfide shows few adverse biological effects and can be deposited as a thin film through less hazardous methods.[11][14]

Thin films β-In2S3 can be grown with varying band gaps, which make them widely applicable as photovoltaic semiconductors, especially in heterojunction solar cells.[11]

Plates coated with beta-In2S3 nanoparticles can be used efficiently for PEC (photoelectrochemical) water splitting.[15]

Biomedical

edit

A preparation of indium sulfide made with the radioactive 113In can be used as a lung scanning agent for medical imaging.[16] It is taken up well by lung tissues, but does not accumulate there.

Other

edit

In2S3 nanoparticles luminesce in the visible spectrum. Preparing In2S3 nanoparticles in the presence of other heavy metal ions creates highly efficient blue, green, and red phosphors, which can be used in projectors and instrument displays.[17]

References

edit
  1. ^ GHS: Alpha Aesar 045563
  2. ^ Indium Sulfide. indium.com
  3. ^ Indium Sulfide. indium.com
  4. ^ Reich, F.; Richter, Th. (1863). "Vorläufige Notiz über ein neues Metal". J. Prakt. Chem. (in German). 89: 441–448. doi:10.1002/prac.18630890156.
  5. ^ Bahadur, D. Inorganic Materials: Recent Advances. Alpha Sciences International, Ltd., 2004. 106
  6. ^ Steigmann, G.A.; Sutherland, H.H.; Goodyear, J. (1965). “The Crystal Structure of -In2S3 “. Acta Crystallogr., 19: 967-971.
  7. ^ a b c Chai, B.; Peng, T.; Zeng, P.; Mao, J. (2011.) “Synthesis of Floriated In2S3 Decorated With TiO2 Nanoparticles for Photocatalytic Hydrogen Production Under Visible Light.” J. Mater. Chem., 21: 14587. doi:10.1039/c1jm11566a.
  8. ^ Barreau, N.; Marsillac, S.; Albertini, D.; Bernede, J.C. (2002). "Structural, optical and electrical properties of β-In2S3-3xO3x thin films obtained by PVD". Thin Solid Films. 403: 331–334.
  9. ^ Haggata, S. W.; Malik, M. Azad; Motevalli, M.; O'Brien, P.; Knowles, J. C. (1995). "Synthesis and Characterization of Some Mixed Alkyl Thiocarbamates of Gallium and Indium, Precursors for III/VI Materials: The X-ray Single-Crystal Structures of Dimethyl- and Diethylindium Diethyldithiocarbamate". Chem. Mater. 7 (4): 716–724. doi:10.1021/cm00052a017.
  10. ^ Otto, K.; Katarski, A.; Mere, O.; Volobujeva, M. (2009). “Spray Pyrolysis Deposition of Indium Sulphide Thin Films.” Thin Solid Films, 519(10): 3055-3060. doi:10.1016/j.tsf.2010.12.027
  11. ^ a b c d Calixto-Rodriguez, M.; Tiburcio-Silver, A.; Ortiz, A.; Sanchez-Juarez, A. (2004.) “Optoelectronical Properties of Indium Sulfide Thin Films Prepared by Spray Pyrolysis for Photovoltaic Applications.” Thin Solid Films, 480: 133-137. doi:10.1016/j/tsf.2004.11.046.
  12. ^ a b Ni, Bing; Liu, Huiling; Wang, Peng-Peng; He, Jie; Wang, Xun (2015). "General synthesis of inorganic single-walled nanotubes". Nat. Commun. 6: 8756. Bibcode:2015NatCo...6.8756N. doi:10.1038/ncomms9756. PMC 4640082. PMID 26510862.
  13. ^ Sigma-Aldrich. (2015) “Safety Data Sheet Version 4.5.” Aldrich – 308293.
  14. ^ a b Karthikeyan, S.; Hill, A.E.; Pilkington, R.D. (2016). “Low Temperature Pulsed Direct Current Magnetron Sputtering Technique for Single Phase -In2S3 Buffer Layers for Solar Cell Applications.” Appl. Surf. Sci. 418: 199-206. doi:10.1016/j.apsusc.2017.01.14
  15. ^ Tian, Y.; Wang, L.; Tang, H.; Zhou, W. (2015). “Ultrathin Two-Dimensional -In2S3 Nanocrystals: Oriented-AttachmentGrowth Controlled By Metal Ions and Photoelectrochemical Properties.” J. Mater. Chem. A, 3: 11294, doi:10.1039/c5ta01958c.
  16. ^ Csetenyi, J.; Szamel, S.I.; Fyzy, M.; Karika, Z. (1974). “Albumin Macroaggregates Containing 113mIn-sulfide (113mIn SMAA): Technique for the Preparation of a New Lung Scanning Agent.” Proc. Int. Symp. Nucl. Med., 3: 293-301.
  17. ^ Chen, W.; Bovin, J.; Joly, A.; Wang, S.; Su, F.; Li, G. (2004). “Full-Color Emission from In2S3 and In2S3:Eu3+ Nanoparticles.” J. Phys. Chem. B, 108: 11927-11934. doi:10.1021/jp048107m.

General references

edit