Manganese dioxide

<p>Manganese dioxide is the <a href="/facts/Inorganic_compound/TfFfzxSz">inorganic compound</a> with the <a href="/facts/Chemical_formula/hghUtthl">formula</a> MnO2. This blackish or brown solid occurs naturally as the mineral <a href="/facts/Pyrolusite/dnS0c7NK">pyrolusite</a>, which is the main ore of <a href="/facts/Manganese/j9ELd1TL">manganese</a> and a component of <a href="/facts/Manganese_nodule/e9RCgkFo">manganese nodules</a>. The principal use for MnO2 is for dry-cell <a href="/facts/Battery_(electricity)/bqEpm4ue">batteries</a>, such as the <a href="/facts/Alkaline_battery/gL5XUWo4">alkaline battery</a> and the <a href="/facts/Zinc%25E2%2580%2593carbon_battery/MDC00Uuh">zinc–carbon battery</a>, although it is also used for other battery chemistries such as <a href="/facts/Aqueous_solution/eRNr3MH2">aqueous</a> <a href="/facts/Zinc-ion_battery/eGQokehT">zinc-ion batteries.</a> MnO2 is also used as a <a href="/facts/Pigment/I3clCYkF">pigment</a> and as a precursor to other manganese compounds, such as <a href="/facts/Potassium_permanganate/nyjjuDlo">KMnO4</a>.  It is used as a <a href="/facts/Reagent/c3GLInCu">reagent</a> in <a href="/facts/Organic_synthesis/WLFePEzH">organic synthesis</a>, for example, for the oxidation of <a href="/facts/Allylic/CDxPwyvF">allylic</a> <a href="/facts/Alcohol_(chemistry)/Y0SCTDkh">alcohols</a>. MnO2 has an α-<a href="/facts/Polymorphism_(materials_science)/bu2tqsB9">polymorph</a> that can incorporate a variety of atoms (as well as water molecules) in the "tunnels" or "channels" between the manganese oxide octahedra. There is considerable interest in α-MnO2 as a possible cathode for <a href="/facts/Lithium-ion_battery/3L22xFhB">lithium-ion batteries</a>.
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Manganese dioxide open-in-new

Manganese dioxide