Editing Selenium (section)

===Other uses===
The demand for selenium by the electronics industry is declining.<ref name="usgs" /> Its [[photovoltaics|photovoltaic]] and [[photoconductivity|photoconductive]] properties are still useful in [[photocopying]],<ref>{{cite journal|doi =10.1080/03086648808079729|title =Application of Selenium-Tellurium Photoconductors to the Xerographic Copying and Printing Processes|date =1988|last1 =Springett|first1 = B. E.|journal =Phosphorus and Sulfur and the Related Elements|volume =38|issue =3–4|pages =341–350}}</ref><ref>{{cite book|url =https://books.google.com/books?id=y1BuoXpPX3kC&pg=PA547| pages =547–548|title =Computer Systems Architecture: A Networking Approach|isbn =978-0-321-34079-5|last=Williams |first=Rob|date =2006| publisher= Prentice Hall}}</ref><ref>{{cite book|chapter-url =https://books.google.com/books?id=y8U4HGZP_O0C&pg=PA81| pages= 81–83| chapter= The Laser Printer|publisher =Wiley-VCH|title =Lasers|isbn =978-3-527-64005-8|last1=Diels |first1=Jean-Claude|last2=Arissian |first2=Ladan|date =2011}}</ref><ref>{{cite book|url =https://books.google.com/books?id=BiOxDxNMeyoC&pg=PA3| pages=3–5| publisher = Springer|title =Organic Electronics|isbn =978-3-642-04537-0|author =Meller, Gregor|author2 =Grasser, Tibor|name-list-style =amp|date =2009}}</ref><!--The use of tellurium-doped selenium was first displaced by amorphous silicon and now organic photosensitive polymers took over making the selenium drums obsolete technology.--> [[photocell]]s, [[light meter]]s and [[solar cell]]s. Its use as a photoconductor in plain-paper copiers once was a leading application, but in the 1980s, the photoconductor application declined (although it was still a large end-use) as more and more copiers switched to organic photoconductors.{{Citation needed|date=June 2024}}

[[Zinc selenide]] was the first material for blue [[LED]]s, but [[gallium nitride]] dominates that market.<ref>{{cite book |last=Normile |first=Dennis |title=Popular Science |date=2000 |page=57 |chapter=The birth of the Blues |chapter-url=https://books.google.com/books?id=D2zyNlMu7kkC&pg=PA57}}</ref> [[Cadmium selenide]] can be used to make [[quantum dot]]s.<ref>{{cite journal|doi=10.1021/ed300568e |title=Simple Syntheses of CdSe Quantum Dots |date=2014 |last1=Landry |first1=Matthew L. |last2=Morrell |first2=Thomas E. |last3=Karagounis |first3=Theodora K. |last4=Hsia |first4=Chih-Hao |last5=Wang |first5=Chia-Ying |journal=Journal of Chemical Education |volume=91 |issue=2 |pages=274–279 |bibcode=2014JChEd..91..274L }}</ref> Sheets of amorphous selenium convert [[X-ray]] images to patterns of charge in [[xeroradiography]] and in solid-state, flat-panel X-ray cameras.<ref>{{cite journal |last1=Kasap |first1=Safa |last2=Frey |first2=Joel B. |last3=Belev |first3=George |last4=Tousignant |first4=Olivier |last5=Mani |first5=Habib |last6=Laperriere |first6=Luc |last7=Reznik |first7=Alla |last8=Rowlands |first8=John A. |display-authors=3 |date=2009 |title=Amorphous selenium and its alloys from early xeroradiography to high resolution X-ray image detectors and ultrasensitive imaging tubes |journal=Physica Status Solidi B |volume=246 |issue=8 |pages=1794–1805 |bibcode=2009PSSBR.246.1794K |doi=10.1002/pssb.200982007 |s2cid=122848842}}</ref> Ionized selenium (Se+24, where 24 of the outer D, S and P orbitals are stripped away due to high input energies{{clarify|date=April 2023}}) is one of the active mediums used in X-ray lasers.<ref>{{Cite book |last=Svelto |first=Orazio |title=Principles of LASERs fourth ed |publisher=Plenum |year=1998 |isbn=978-0-306-45748-7 |pages=457}}</ref> <sup>75</sup>Se is used as a gamma source in industrial radiography.<ref>{{cite news |last1=Hayward |first1=Peter |last2=Currie |first2=Dean |title=Radiography of Welds Using Selenium 75, Ir 192 and X-rays |url=http://www.ndt.net/article/apcndt2006/papers/12.pdf}}</ref>

Selenium catalyzes some chemical reactions, but it is not widely used because of issues with toxicity.<ref>{{Cite journal|url=https://pubs.rsc.org/en/content/articlehtml/2019/cy/c8cy02274g|doi = 10.1039/C8CY02274G|title = Selenium reagents as catalysts|year = 2019|last1 = Singh|first1 = Fateh V.|last2 = Wirth|first2 = Thomas|journal = Catalysis Science & Technology|volume = 9|issue = 5|pages = 1073–1091|s2cid = 104468775}}</ref> In [[X-ray crystallography]], incorporation of one or more selenium atoms in place of sulfur helps with multiple-wavelength anomalous dispersion and [[single wavelength anomalous dispersion]] phasing.<ref>{{cite journal|doi= 10.1098/rspa.1993.0087|title= New Techniques of Applying Multi-Wavelength Anomalous Scattering Data|date= 1993|last1= Hai-Fu|first1= F.|last2= Woolfson|first2=M. M.|last3= Jia-Xing|first3= Y.|journal= Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences|volume= 442|issue= 1914|pages= 13–32|bibcode= 1993RSPSA.442...13H |s2cid= 122722520}}</ref>

Selenium is used in the [[photographic print toning|toning of photographic prints]], and it is sold as a toner by numerous photographic manufacturers. Selenium intensifies and extends the tonal range of black-and-white photographic images and improves the permanence of prints.<ref>{{cite journal |last=MacLean |first=Marion E. |date=1937 |title=A project for general chemistry students: Color toning of photographic prints |journal=Journal of Chemical Education |volume=14 |issue=1 |page=31 |bibcode=1937JChEd..14...31M |doi=10.1021/ed014p31}}</ref><ref>{{cite journal |last=Penichon |first=Sylvie |date=1999 |title=Differences in Image Tonality Produced by Different Toning Protocols for Matte Collodion Photographs |journal=Journal of the American Institute for Conservation |volume=38 |issue=2 |pages=124–143 |doi=10.2307/3180042 |jstor=3180042}}</ref><ref>{{cite book |last=McKenzie |first=Joy |url=https://archive.org/details/exploringbasicbl0000mcke |title=Exploring Basic Black & White Photography |date=2003 |publisher=Delmar |isbn=978-1-4018-1556-1 |page=[https://archive.org/details/exploringbasicbl0000mcke/page/176 176] |url-access=registration}}</ref> Small amounts of organoselenium compounds have been used to modify the catalysts used for the [[sulfur vulcanization|vulcanization]] for the production of rubber.<ref name="Naumov" /> Selenium is used in some anti-dandruff shampoos in the form of [[selenium disulfide]] such as Selsun and Vichy Dereos<ref>{{Cite web |title=What is Dandruff? |url=https://www.vichy.co.uk/on/demandware.static/-/Sites-vic-master-catalog/default/dw41dcc5e7/VIC/ProductImages/Blog-Imagery-Vichy/Vichy_Customer_Leaflet_Dandruff.pdf |access-date=3 October 2023 |website=Vichy UK}}</ref> brands.