Editing Indium (section)

==Applications==
===Industrial uses===
[[File:Dell axim LCD under microscope.jpg|thumb|right|A magnified image of an [[TFT LCD|LCD]] screen showing RGB pixels. Individual transistors are seen as white dots in the bottom part.]]
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|access-date = 2009-12-03|archive-date = 2016-12-31|archive-url = https://web.archive.org/web/20161231013853/https://minerals.usgs.gov/mineralofthemonth/indium.pdf|url-status = live}}</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(III) oxide and [[indium tin oxide]] (ITO) are used as a [[transparency (optics)|transparent]] [[electrical conductor|conductive]] coating on [[glass]] substrates in [[electroluminescent]] panels.<ref>{{cite web|title=The Electroluminescent Light Sabre |work=Nanotechnology News Archive |publisher=Azonano |date=June 2, 2005 |url=http://azonano.com/news.asp?newsID=1007 |access-date=2007-08-29  |archive-url=https://web.archive.org/web/20071012003936/http://azonano.com/news.asp?newsID=1007 |archive-date=October 12, 2007 }}</ref> Indium tin oxide is used as a light filter in [[sodium-vapor lamp#Low-pressure sodium|low-pressure sodium-vapor lamps]]. The [[infrared radiation]] is reflected back into the lamp, which increases the temperature within the tube and improves the performance of the lamp.<ref name="Downs" />

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 name="shenai2004" /> 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
| volume = 361–362| issue = 1–2|date = 2000| pages = 540–546|doi = 10.1016/S0040-6090(99)00849-4|first = M.|last = Powalla|author2=Dimmler, B.|journal = Thin Solid Films|bibcode=2000TSF...361..540P}}</ref> Indium is used in PNP [[bipolar junction transistor]]s with [[germanium]]: when soldered at low temperature, indium does not stress the germanium.<ref name="Greenwood247" />

[[File:Indium wire.jpg|thumb|left|Ductile indium wire]]
[[File:Indium Lung Disease.webm|thumb|left|A video on [[indium lung]], an illness caused by indium exposure]]
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 is one of many substitutes for mercury in [[alkaline batteries]] to prevent the [[zinc]] from corroding and releasing [[hydrogen]] gas.<ref>{{cite book|title=Minerals Yearbook, 2008, V. 1, Metals and Minerals|author=Geological Survey (U.S.)|date=2010|pages=35–2|publisher=Government Printing Office|isbn=978-1-4113-3015-3}}</ref> Indium is added to some [[dental amalgam]] alloys to decrease the [[surface tension]] of the mercury and allow for less mercury and easier amalgamation.<ref>{{cite journal|author=Powell L. V. |author2=Johnson G. H. |author3=Bales D. J. |title=Effect of Admixed Indium on Mercury Vapor Release from Dental Amalgam|journal=Journal of Dental Research|volume=68|issue=8|pages=1231–3|doi=10.1177/00220345890680080301|pmid=2632609|year=1989|citeseerx=10.1.1.576.2654|s2cid=28342583}}</ref>

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 <sup>113</sup>In and <sup>115</sup>In 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>

In 2009, Professor [[Mas Subramanian]] and former graduate student Andrew Smith at [[Oregon State University]] discovered that indium can be combined with [[yttrium]] and [[manganese]] to form an intensely [[blue]], non-toxic, inert, fade-resistant [[pigment]], [[YInMn blue]], the first new inorganic blue pigment discovered in 200 years.<ref name="Kupferschmidt pp. 424–429">{{cite journal | last=Kupferschmidt | first=Kai | title=In search of blue | journal=Science | publisher=American Association for the Advancement of Science (AAAS) | volume=364 | issue=6439 | date=2019-05-02 | issn=0036-8075 | doi=10.1126/science.364.6439.424 | pages=424–429| pmid=31048474 | bibcode=2019Sci...364..424K | s2cid=143434096 }}</ref>

===Medical applications===
Radioactive indium-111 (in very small amounts) is used in [[nuclear medicine]] tests, as a [[radiotracer]] to follow the movement of labeled proteins and [[indium leukocyte imaging|white blood cells]] to diagnose different types of infection.<ref name="Indium-111 Radiochemical Indium Chloride Solution">{{cite web|title=IN-111 FACT SHEET|url=http://www.nordion.com/documents/products/In-111_Can.pdf|publisher=Nordion(Canada), Inc.|access-date=23 September 2012|archive-url=https://web.archive.org/web/20111203082605/http://www.nordion.com/documents/products/In-111_Can.pdf|archive-date=3 December 2011}}</ref><ref>{{cite journal |last1=Van Nostrand |first1=D. |last2=Abreu |first2=S. H. |last3=Callaghan |first3=J. J. |last4=Atkins |first4=F. B. |last5=Stoops |first5=H. C. |last6=Savory |first6=C. G. |date=May 1988 |title=In-111-labeled white blood cell uptake in noninfected closed fracture in humans: prospective study |journal=Radiology |volume=167 |issue= 2|pages=495–498 |pmid=3357961 | doi = 10.1148/radiology.167.2.3357961}}</ref> Indium compounds are mostly not absorbed upon ingestion and are only moderately absorbed on inhalation; they tend to be stored temporarily in the [[muscle]]s, [[skin]], and [[bone]]s before being excreted, and the [[biological half-life]] of indium is about two weeks in humans.<ref>{{cite book |first1=Gunnar F. |last1=Nordberg |first2=Bruce A. |last2=Fowler |first3=Monica |last3=Nordberg |title=Handbook on the Toxicology of Metals |publisher=Academic Press |page=845 |edition=4th |date=7 August 2014 |isbn=978-0-12-397339-9}}</ref> It is also tagged to [[growth hormone]] analogues like [[octreotide]] to find [[growth hormone]] receptors in [[neuroendocrine tumors]].<ref>{{cite journal |pmid=1349039 |date=1992 |last1=Krenning |first1=E. P. |last2=Bakker |first2=W. H. |last3=Kooij |first3=P. P. |last4=Breeman |first4=W. A. |last5=Oei |first5=H. Y. |last6=De Jong |first6=M. |last7=Reubi |first7=J. C. |last8=Visser |first8=T. J. |last9=Bruns |first9=C. |last10=Kwekkeboom |first10=D. J. |title=Somatostatin receptor scintigraphy with indium-111-DTPA-D-Phe-1-octreotide in man: Metabolism, dosimetry and comparison with iodine-123-Tyr-3-octreotide |journal=Journal of Nuclear Medicine |volume=33 |issue=5 |pages=652–658 }}</ref>