Editing Manganese (section)

===Aluminium alloys===
{{Main|Aluminium alloy}}
Manganese is used in production of alloys with aluminium. Aluminium with roughly 1.5% manganese has increased resistance to corrosion through grains that absorb impurities which would lead to [[galvanic corrosion]].<ref>{{cite web |url=http://www.suppliersonline.com/propertypages/2024.asp|title=Chemical properties of 2024 aluminum allow|access-date=30 April 2009 |publisher=Metal Suppliers Online, LLC.}}</ref> The corrosion-resistant [[aluminium alloy]]s 3004 and 3104 (0.8 to 1.5% manganese) are used for most [[beverage can]]s.<ref name="Al3004">{{cite book |title=Introduction to aluminum alloys and tempers|first=John Gilbert |last=Kaufman|publisher=ASM International|date=2000|isbn=978-0-87170-689-8|chapter=Applications for Aluminium Alloys and Tempers |pages=93–94|chapter-url=https://books.google.com/books?id=idmZIDcwCykC&pg=PA93}}</ref> Before 2000, more than 1.6&nbsp;million [[tonne]]s of those alloys were used; at 1% manganese, this consumed 16,000 tonnes of manganese.<ref name="Al3004"/>

====Batteries====
[[Manganese(IV) oxide]] was used in the original type of dry cell [[Battery (electricity)|battery]] as an electron acceptor from zinc, and is the blackish material in carbon–zinc type flashlight cells. The manganese dioxide is reduced to the manganese oxide-hydroxide MnO(OH) during discharging, preventing the formation of hydrogen at the anode of the battery.<ref name="BattHist"/>

:MnO<sub>2</sub> + H<sub>2</sub>O + e<sup>−</sup> → MnO(OH) + {{chem|OH|-}}

The same material also functions in newer [[Alkaline battery|alkaline batteries]] (usually battery cells), which use the same basic reaction, but a different electrolyte mixture. In 2002, more than 230,000&nbsp;tons of manganese dioxide was used for this purpose.<ref name="ChiuZMnO2" /><ref name="BattHist">{{cite journal|doi=10.1016/S0167-2738(00)00722-0|title=Batteries fifty years of materials development|date=2000|last=Dell|first=R. M.|journal=Solid State Ionics|volume=134|issue=1–2|pages=139–158}}</ref>

====Resistors====
Copper alloys of manganese, such as [[Manganin]], are commonly found in metal element [[shunt resistor]]s used for measuring relatively large amounts of current. These alloys have very low [[temperature coefficient of resistance]] and are resistant to sulfur. This makes the alloys particularly useful in harsh automotive and industrial environments.<ref>{{cite book |author1=David B. Wellbeloved |author2=Peter M. Craven |author3=John W. Waudby |title=Ullmann's Encyclopedia of Industrial Chemistry |date=2000 |publisher=Wiley |isbn=9783527306732 |language=en |chapter=Manganese and Manganese Alloys |doi=10.1002/14356007.a16_077}}</ref><ref name="ShuntDatasheet">{{cite web |title=WSK1216 |url=https://www.vishay.com/docs/30189/wsk1216.pdf |website=vishay |publisher=Vishay Intertechnology |access-date=30 April 2022}}</ref>

====Fertilizers and feed additive====
[[Manganese(II) oxide|Manganese oxide]] and [[Manganese sulfate|sulfate]] are components of fertilizers. In the year 2000, an estimated 20,000 tons of these compounds were used in fertilizers in the US alone.  A comparable amount of Mn compounds was also used in animal feeds.<ref name="ullmann">{{cite book |doi=10.1002/14356007.a16_123 |chapter=Manganese Compounds |title=Ullmann's Encyclopedia of Industrial Chemistry |date=2000 |last1=Reidies |first1=Arno H. |isbn=9783527303854 }}</ref>

====Niche====
[[Methylcyclopentadienyl manganese tricarbonyl]] is an additive in some [[unleaded gasoline]] to boost [[octane rating]] and reduce [[engine knocking]].<ref>{{cite web |title=EPA Comments on the Gasoline Additive MMT |url=https://www.epa.gov/gasoline-standards/epa-comments-gasoline-additive-mmt |website=epa.gov |date=5 October 2015 |publisher=EPA |access-date=25 June 2023}}</ref>

Manganese(IV) oxide (manganese dioxide, MnO<sub>2</sub>) is used as a reagent in [[organic chemistry]] for the [[oxidation]] of benzylic [[Alcohol (chemistry)|alcohol]]s (where the [[hydroxyl]] group is adjacent to an [[aromatic ring]]).<ref>{{cite book |author1=Gérard Cahiez |author2=Mouâd Alami |author3=Richard J. K. Taylor |author4=Mark Reid |author5=Jonathan S. Foot |author6=Lee Fader |author7=Vikas Sikervar |author8=Jagadish Pabba |title=Encyclopedia of Reagents for Organic Synthesis |date=2017 |isbn=9780470842898 |chapter=Manganese Dioxide |doi = 10.1002/047084289X.rm021.pub4}}</ref> Manganese dioxide has been used since antiquity to oxidize and neutralize the greenish tinge in glass from trace amounts of iron contamination.<ref name="ItGlass">{{cite journal |doi=10.1007/s11837-998-0024-0|title=Glassmaking in renaissance Italy: The innovation of venetian cristallo|date=1998|last=Mccray |first=W. Patrick|journal=JOM|volume=50|pages=14–19|issue=5|bibcode=1998JOM....50e..14M|s2cid=111314824}}</ref> MnO<sub>2</sub> is also used in the manufacture of oxygen and chlorine and in drying black paints. In some preparations, it is a brown [[pigment]] for [[paint]] and is a constituent of natural [[umber]].<ref name=straightouttathetheumberwikiarticle>{{cite book |title=Shorter Oxford English Dictionary |url=https://archive.org/details/shorteroxfordeng00will_0 |publisher=Oxford University Press |year=2002 |isbn=978-0-19-860457-0 |quote=A red brown earth containing iron and manganese oxides and darker than ochre and sienna, used to make various pigments. |edition=5th}}</ref>

[[Tetravalence|Tetravalent]] manganese is used as an [[Activator (phosphor)|activator]] in red-emitting [[phosphor]]s. While many compounds are known which show [[luminescence]],<ref>{{cite journal|journal=RSC Advances |date=2016|volume=6|issue=89|pages=86285–86296|first=Daquin|last=Chen|author2=Zhou, Yang |author3=Zhong, Jiasong |title=A review on Mn<sup>4+</sup> activators in solids for warm white light-emitting diodes|doi=10.1039/C6RA19584A|bibcode=2016RSCAd...686285C}}</ref> the majority are not used in commercial application due to low efficiency or deep red emission.<ref>{{cite journal|journal=Journal of Luminescence |date=2016|volume=177|pages=354–360|first=Florian|last=Baur|author2=Jüstel, Thomas|title=Dependence of the optical properties of Mn<sup>4+</sup> activated A<sub>2</sub>Ge<sub>4</sub>O<sub>9</sub> (A=K,Rb) on temperature and chemical environment|doi=10.1016/j.jlumin.2016.04.046|bibcode=2016JLum..177..354B}}</ref><ref>{{Cite journal|last1=Jansen|first1=T.|last2=Gorobez|first2=J.|last3=Kirm|first3=M.|last4=Brik|first4=M. G.|last5=Vielhauer|first5=S.|last6=Oja|first6=M.|last7=Khaidukov|first7=N. M.|last8=Makhov|first8=V. N.|last9=Jüstel|first9=T.|date=1 January 2018|title=Narrow Band Deep Red Photoluminescence of Y<sub>2</sub>Mg<sub>3</sub>Ge<sub>3</sub>O<sub>12</sub>:Mn<sup>4+</sup>,Li<sup>+</sup> Inverse Garnet for High Power Phosphor Converted LEDs|journal=ECS Journal of Solid State Science and Technology|volume=7|issue=1|pages=R3086–R3092|doi=10.1149/2.0121801jss|s2cid=103724310 |doi-access=free}}</ref> However, several Mn<sup>4+</sup> activated fluorides were reported as potential red-emitting phosphors for warm-white LEDs.<ref>{{Cite journal|last1=Jansen|first1=Thomas|last2=Baur|first2=Florian|last3=Jüstel|first3=Thomas|title=Red emitting K<sub>2</sub>NbF<sub>7</sub>:Mn<sup>4+</sup> and K<sub>2</sub>TaF<sub>7</sub>:Mn<sup>4+</sup> for warm-white LED applications|journal=Journal of Luminescence|volume=192|pages=644–652|doi=10.1016/j.jlumin.2017.07.061|year=2017|bibcode=2017JLum..192..644J}}</ref><ref>{{Cite journal|last1=Zhou|first1=Zhi|last2=Zhou|first2=Nan|last3=Xia|first3=Mao|last4=Yokoyama|first4=Meiso|last5=Hintzen|first5=H. T. (Bert)|date=6 October 2016|title=Research progress and application prospects of transition metal Mn<sup>4+</sup>-activated luminescent materials|journal=Journal of Materials Chemistry C|volume=4|issue=39|pages=9143–9161|doi=10.1039/c6tc02496c}}</ref> But to this day, only K<sub>2</sub>SiF<sub>6</sub>:Mn<sup>4+</sup> is commercially available for use in warm-white [[LED]]s.<ref>{{cite web|url=https://energy.gov/sites/prod/files/2015/02/f19/setlur_emitters_2015.pdf|title=TriGain LED phosphor system using red Mn<sup>4+</sup>-doped complex fluorides|publisher=GE Global Research |access-date=10 December 2022}}</ref>

[[File:1945-P-Jefferson-War-Nickel-Reverse.JPG|upright|thumb|World-War-II-era 5-cent coin (1942-5 identified by mint mark P, D or S above dome) made from a 56% copper-35% silver-9% manganese alloy]]
The metal is occasionally used in coins; until 2000, the only United States coin to use manganese was the [[Jefferson nickel#1938–1945: Early minting; World War II changes|"wartime" nickel]] from 1942 to 1945.<ref>{{cite journal|journal=Western Journal of Medicine |date=2001|volume=175|issue=2|pages=112–114|first=Raymond T.|last=Kuwahara|author2=Skinner III, Robert B. |author3=Skinner Jr., Robert B. |title=Nickel coinage in the United States|doi=10.1136/ewjm.175.2.112|pmid=11483555|pmc=1071501}}</ref> An alloy of 75% copper and 25% nickel was traditionally used for the production of nickel coins. However, because of shortage of nickel metal during the war, it was substituted by more available silver and manganese, thus resulting in an alloy of 56% copper, 35% silver and 9% manganese. Since 2000, [[Dollar (United States coin)|dollar coins]], for example the [[Sacagawea dollar]] and the [[Presidential $1 Coin Program|Presidential $1 coins]], are made from a brass containing 7% of manganese with a pure copper core.<ref>{{cite web|url=http://www.usmint.gov/mint_programs/golden_dollar_coin/index.cfm?action=sacDesign|title=Design of the Sacagawea dollar|publisher=United States Mint|access-date=4 May 2009|archive-date=22 April 2021|archive-url=https://web.archive.org/web/20210422194127/https://www.usmint.gov/learn/coin-and-medal-programs?action=sacdesign|url-status=dead}}</ref>

Manganese compounds have been used as pigments and for the coloring of ceramics and glass. The brown color of ceramic is sometimes the result of manganese compounds.<ref>{{cite book|title=Ceramics for the Archaeologist|first=Anna Osler|last=Shepard|publisher=Carnegie Institution of Washington|date=1956|pages=40–42|isbn=978-0-87279-620-1|chapter=Manganese and Iron–Manganese Paints}}</ref> In the glass industry, manganese compounds are used for two effects. [[Manganese(III) oxide|Manganese(III)]] reacts with [[Iron(II) oxide|iron(II)]] to reduce strong green color in glass by forming less-colored iron(III) and slightly pink manganese(II), compensating for the residual color of the iron(III).<ref name="ItGlass" /> Larger quantities of manganese are used to produce pink colored glass. In 2009, [[Mas Subramanian]] and associates at [[Oregon State University]] discovered that manganese can be combined with [[yttrium]] and [[indium]] to form an intensely [[blue]], non-toxic, inert, fade-resistant [[pigment]], [[YInMn Blue]],<ref>{{Cite journal |last1=Li |first1=Jun |last2=Lorger |first2=Simon |last3=Stalick |first3=Judith K. |last4=Sleight |first4=Arthur W. |last5=Subramanian |first5=M. A. |date=2016-10-03 |title=From Serendipity to Rational Design: Tuning the Blue Trigonal Bipyramidal Mn 3+ Chromophore to Violet and Purple through Application of Chemical Pressure |url=https://pubs.acs.org/doi/10.1021/acs.inorgchem.6b01639 |journal=Inorganic Chemistry |language=en |volume=55 |issue=19 |pages=9798–9804 |doi=10.1021/acs.inorgchem.6b01639 |pmid=27622607 |issn=0020-1669}}</ref> the first new blue pigment discovered in 200 years.<ref>{{cite web |url=https://ideas.ted.com/how-on-earth-do-you-discover-a-brand-new-blue-pigment-by-accident/ |title=How on earth do you discover a brand-new blue pigment? By accident. |date=June 28, 2018 |first=Elian |last=Silverman |publisher=TED Ideas |access-date=June 26, 2024}}</ref>