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Niobium pentoxide is the inorganic compound with the formula Nb 2 O 5. A colorless, insoluble, and fairly unreactive solid, it is the most widespread precursor for other compounds and materials containing niobium. It is predominantly used in alloying, with other specialized applications in capacitors, optical glasses, and the production of ...
Niobium oxide, archaically called columbium oxide, [1] may refer to: Niobium monoxide (niobium(II) oxide), NbO; Niobium dioxide (niobium(IV) oxide), NbO 2; Niobium pentoxide (niobium(V) oxide), Nb 2 O 5; In addition to the above, other distinct oxides exist general formula Nb 3n+1 O 8n−2 where n ranges from 5 - 8 inclusive, e.g. Nb 8 O 19 (Nb ...
Niobium forms oxides in the oxidation states +5 (Nb 2 O 5), [77] +4 (NbO 2), and the rarer oxidation state, +2 . [78] Most common is the pentoxide, precursor to almost all niobium compounds and alloys. [61] [79] Niobates are generated by dissolving the pentoxide in basic hydroxide solutions or by melting it in alkali metal oxides.
The niobate can be obtained by reacting niobium pentoxide with the corresponding oxide, hydroxide or carbonate. [1] For example, reacting lithium carbonate with niobium pentoxide would obtain lithium niobate: [2] Li 2 CO 3 + Nb 2 O 5 → 2 LiNbO 3 + CO 2 ↑. Cobalt metaniobate can be obtained by heating a mixture of cobalt monoxide and niobium ...
Ferroniobium is an important iron-niobium alloy, with a niobium content of 60-70%. [1] It is the main source for niobium alloying of HSLA steel and covers more than 80% of the worldwide niobium production. The niobium is mined from pyrochlore deposits and is subsequently transformed into the niobium pentoxide Nb 2 O 5.
A niobium electrolytic capacitor (historically also Columbium capacitor [1] [2]) is an electrolytic capacitor whose anode (+) is made of passivated niobium metal or niobium monoxide, on which an insulating niobium pentoxide layer acts as a dielectric.
The aluminothermic reaction is used for the production of several ferroalloys, for example ferroniobium from niobium pentoxide and ferrovanadium from iron, vanadium(V) oxide, and aluminium. [1] [2] The process begins with the reduction of the oxide by the aluminium: 3 V 2 O 5 + 10 Al → 5 Al 2 O 3 + 6 V
The salt is prepared by dissolving niobium pentoxide in a solution of potassium bifluoride in 40% hydrofluoric acid: [4] Nb 2 O 5 + 4 KHF 2 + 6 HF → 2K 2 NbF 7 + 5 H 2 O. Potassium heptafluoroniobate and potassium heptafluorotantalate are isostructural. The anion has approximate C 2v symmetry, being a face-capped trigonal prism. The Nb-F ...