Indium: Difference between revisions

===Isotopes===

{{Main|Isotopes of indium}}

 

The stablest [[synthetic radioisotope|artificial]] isotope is [[indium-111]], with a half-life of approximately 2.8&nbsp;days. All other isotopes have half-lives shorter than 5 hours. Indium also has 47 meta states, among which indium-114m1 (half-life about 49.51&nbsp;days) is the most stable, more stable than the ground state of any indium isotope other than the primordial. All decay by [[isomeric transition]]. The indium isotopes lighter than ¹¹⁵In predominantly decay through [[electron capture]] or [[positron emission]] to form [[cadmium]] isotopes, while the other indium isotopes from ¹¹⁵In and greater predominantly decay through beta-minus decay to form tin isotopes.<ref name="Audi" />

In 1863, the German chemists [[Ferdinand Reich]] and [[Hieronymous Theodor Richter]] were testing ores from the mines around [[Freiberg, Saxony]]. They dissolved the minerals [[pyrite]], [[arsenopyrite]], [[galena]] and [[sphalerite]] in [[hydrochloric acid]] and distilled raw [[zinc chloride]]. Reich, who was [[color-blind]], employed Richter as an assistant for detecting the colored spectral lines. Knowing that ores from that region sometimes contain [[thallium]], they searched for the green thallium emission spectrum lines. Instead, they found a bright blue line. Because that blue line did not match any known element, they hypothesized a new element was present in the minerals. They named the element indium, from the [[indigo]] color seen in its spectrum, after the Latin ''indicum'', meaning 'of [[India]]'.<ref>{{cite journal|title = Ueber das Indium|author = Reich, F.|author2=Richter, T.|journal = Journal für Praktische Chemie|volume = 90|issue = 1|pages = 172–176|date = 1863|doi = 10.1002/prac.18630900122| s2cid=94381243 |language=de|url = https://zenodo.org/record/1427838}}</ref><ref name="Venetskii">{{cite journal|title = Indium|last = Venetskii|first = S.|journal = Metallurgist|volume = 15|issue = 2|pages = 148–150|date = 1971|doi = 10.1007/BF01088126}}</ref><ref name="Greenwood244">Greenwood and Earnshaw, p. 244</ref><ref name="Weeks">{{cite journal|author=Weeks, Mary Elvira |author-link=Mary Elvira Weeks |title=The Discovery of the Elements: XIII. Some Spectroscopic Studies |journal=Journal of Chemical Education |volume=9 |issue=8 |pages=1413–1434 |url=http://search.jce.divched.org/JCEIndex/FMPro?-db=jceindex.fp5&-lay=wwwform&combo=weeks&-find=&-format=detail.html&-skip=27&-max=1&-token.2=27&-token.3=10 |doi=10.1021/ed009p1413 |year=1932 |bibcode=1932JChEd...9.1413W }}{{dead link|date=April 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

 

 

==Occurrence==

China is a leading producer of indium (290 tonnes in 2016), followed by South Korea (195 t), Japan (70 t) and Canada (65 t).<ref name="USGS-2017" /> The [[Teck Resources]] refinery in [[Trail, British Columbia]], is a large single-source indium producer, with an output of 32.5&nbsp;tonnes in 2005, 41.8&nbsp;tonnes in 2004 and 36.1&nbsp;tonnes in 2003.

 

 

==Applications==

In 1924, indium was found to have a valued property of stabilizing [[non-ferrous metals]], and that became the first significant use for the element.<ref name="dd">{{cite journal |doi = 10.1021/ed011p270 |title = A story of indium |date = 1934 |last1 = French |first1 = Sidney J. |journal = Journal of Chemical Education |volume = 11 |issue = 5 |page = 270|bibcode = 1934JChEd..11..270F }}</ref> The first large-scale application for indium was coating [[bearing (mechanical)|bearings]] in high-performance [[aircraft]] engines during [[World War II]], to protect against damage and [[corrosion]]; this is no longer a major use of the element.<ref name="Greenwood247" /> New uses were found in [[fusible alloy]]s, [[solder]]s, and [[electronics]]. In the 1950s, tiny beads of indium were used for the emitters and collectors of PNP [[alloy-junction transistor]]s. In the middle and late 1980s, the development of [[indium phosphide]] [[semiconductor]]s and [[indium tin oxide]] thin films for [[liquid-crystal display]]s (LCD) aroused much interest. By 1992, the thin-film application had become the largest end use.<ref name="USGSYB2007">{{cite web|title = Mineral Yearbook 2007: Indium|publisher = United States Geological Survey|first = Amy C.|last = Tolcin|url =http://minerals.usgs.gov/mineralofthemonth/indium.pdf}}</ref><ref name="Downs">{{cite book|title = Chemistry of Aluminium, Gallium, Indium, and Thallium |first =Anthony John|last = Downs|publisher = Springer|date = 1993|isbn = 978-0-7514-0103-5|pages = 89 and 106|url = https://books.google.com/books?id=v-04Kn758yIC}}</ref>

 

 

Indium has many [[semiconductor]]-related applications. Some indium compounds, such as [[indium antimonide]] and [[indium phosphide]],<ref>{{cite journal|title = Properties, Preparation, and Device Applications of Indium Phosphide|journal = [[Annual Review of Materials Science]]|volume = 11|pages = 441–484|date = 1981|doi = 10.1146/annurev.ms.11.080181.002301|first = K. J.|last = Bachmann|bibcode = 1981AnRMS..11..441B }}</ref> are [[semiconductor]]s with useful properties: one precursor is usually [[trimethylindium]] (TMI), which is also used as the [[semiconductor]] [[dopant]] in II–VI [[compound semiconductor]]s.<ref>{{cite journal|title = Correlation of film properties and reduced impurity concentrations in sources for III/V-MOVPE using high-purity trimethylindium and tertiarybutylphosphine|first = Deodatta V.|last = Shenai|author2 = Timmons, Michael L. |author3 = DiCarlo Jr., Ronald L. |author4 = Marsman, Charles J.|journal = Journal of Crystal Growth|volume = 272|issue = 1–4|date = 2004|pages = 603–608 |doi = 10.1016/j.jcrysgro.2004.09.006|bibcode = 2004JCrGr.272..603S }}</ref> InAs and InSb are used for low-temperature transistors and InP for high-temperature transistors.<ref name="Greenwood247" /> The [[compound semiconductor]]s [[InGaN]] and [[InGaP]] are used in [[light-emitting diode]]s (LEDs) and laser diodes.<ref>{{cite book|isbn=978-0-521-53351-5|title=Light-Emitting Diodes|author=Schubert, E. Fred |date=2003|page=16|publisher=Cambridge University Press}}</ref> Indium is used in [[photovoltaics]] as the semiconductor [[copper indium gallium selenide]] (CIGS), also called [[CIGS solar cell]]s, a type of second-generation [[thin-film solar cell]].<ref>{{cite journal|title = Scaling up issues of CIGS solar cells

Indium wire is used as a [[cryogenic seal|vacuum seal]] and a thermal conductor in [[cryogenics]] and [[ultra-high vacuum|ultra-high-vacuum]] applications, in such manufacturing applications as [[gasket]]s that deform to fill gaps.<ref>{{Cite book|url = https://books.google.com/books?id=tfLWfAx1ZWQC&pg=PA296|page = 296|isbn = 978-0-12-475914-5|editor= Weissler, G. L. |date = 1990|publisher = Acad. Press|location = San Diego|title = Vacuum physics and technology}}</ref> Owing to its great plasticity and adhesion to metals, Indium sheets are sometimes used for cold-soldering in [[Microwave engineering|microwave]] circuits and [[waveguide]] joints, where direct soldering is complicated. Indium is an ingredient in the gallium–indium–tin alloy [[galinstan]], which is liquid at room temperature and replaces [[mercury (element)|mercury]] in some [[thermometer]]s.<ref>{{cite journal|doi=10.1007/s00216-005-0069-7|date=Nov 2005|author=Surmann, P|author2=Zeyat, H| title=Voltammetric analysis using a self-renewable non-mercury electrode| volume=383|issue=6|pages=1009–13| pmid=16228199|journal= Analytical and Bioanalytical Chemistry|s2cid=22732411}}</ref> Other alloys of indium with [[bismuth]], [[cadmium]], [[lead]], and [[tin]], which have higher but still low melting points (between 50 and 100&nbsp;°C), are used in [[fire sprinkler system]]s and heat regulators.<ref name="Greenwood247" />

 

 

Indium's high neutron-capture cross-section for thermal neutrons makes it suitable for use in [[control rod]]s for [[nuclear reactors]], typically in an alloy of 80% [[silver]], 15% indium, and 5% [[cadmium]].<ref>{{cite book | chapter-url = https://books.google.com/books?id=9yzN-QGag_8C&pg=PA222 | page = 222 | chapter= Other types of cadmium alloys | title = Mercury, cadmium, lead: handbook for sustainable heavy metals policy and regulation | isbn = 978-1-4020-0224-3 | author1 = Scoullos, Michael J. | date = 2001-12-31| publisher = Springer }}</ref> In nuclear engineering, the (n,n') reactions of ¹¹³In and ¹¹⁵In are used to determine magnitudes of neutron fluxes.<ref>{{cite book | chapter-url = https://books.google.com/books?id=b1ZwQXdxAtUC&pg=PA50 | pages = 50–51 | chapter = Image Detectors for Other Neutron Energies | title = Practical applications of neutron radiography and gaging: a symposium | author1 = Berger, Harold | author2 = National Bureau Of Standards, United States | author3 = Committee E-7 On Nondestructive Testing, American Society for Testing and Materials | date = 1976}}</ref>

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People can be exposed to indium in the workplace by inhalation, ingestion, skin contact, and eye contact. [[Indium lung]] is a lung disease characterized by pulmonary alveolar proteinosis and pulmonary fibrosis, first described by Japanese researchers in 2003. {{As of|2010}}, 10 cases had been described, though more than 100 indium workers had documented respiratory abnormalities.<ref name="Sauler">{{cite journal|last1=Sauler|first1=Maor|last2=Gulati|first2=Mridu|title=Newly Recognized Occupational and Environmental Causes of Chronic Terminal Airways and Parenchymal Lung Disease|journal=Clinics in Chest Medicine|date=December 2012|volume=33|issue=4|pages=667–680|doi=10.1016/j.ccm.2012.09.002|pmid=23153608|pmc=3515663}}</ref> The [[National Institute for Occupational Safety and Health]] has set a [[recommended exposure limit]] (REL) of 0.1&nbsp;mg/m³ over an eight-hour workday.<ref>{{Cite web|title = CDC – NIOSH Pocket Guide to Chemical Hazards – Indium|url = https://www.cdc.gov/niosh/npg/npgd0341.html|website = www.cdc.gov|access-date = 2015-11-06}}</ref>