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Chemical element, symbol V and atomic number 23 / From Wikipedia, the free encyclopedia

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Vanadium is a chemical element; it has symbol V and atomic number 23. It is a hard, silvery-grey, malleable transition metal. The elemental metal is rarely found in nature, but once isolated artificially, the formation of an oxide layer (passivation) somewhat stabilizes the free metal against further oxidation.

Quick Facts Pronunciation, Appearance ...
Vanadium, 23V
Pronunciation/vəˈndiəm/ (və-NAY-dee-əm)
Appearanceblue-silver-grey metal
Standard atomic weight Ar°(V)
Vanadium in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson


Atomic number (Z)23
Groupgroup 5
Periodperiod 4
Block  d-block
Electron configuration[Ar] 3d3 4s2
Electrons per shell2, 8, 11, 2
Physical properties
Phase at STPsolid
Melting point2183 K (1910 °C, 3470 °F)
Boiling point3680 K (3407 °C, 6165 °F)
Density (near r.t.)6.11 g/cm3
when liquid (at m.p.)5.5 g/cm3
Heat of fusion21.5 kJ/mol
Heat of vaporization444 kJ/mol
Molar heat capacity24.89 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 2101 2289 2523 2814 3187 3679
Atomic properties
Oxidation states−3, −1, 0, +1, +2, +3, +4, +5 (an amphoteric oxide)
ElectronegativityPauling scale: 1.63
Ionization energies
  • 1st: 650.9 kJ/mol
  • 2nd: 1414 kJ/mol
  • 3rd: 2830 kJ/mol
  • (more)
Atomic radiusempirical: 134 pm
Covalent radius153±8 pm
Color lines in a spectral range
Spectral lines of vanadium
Other properties
Natural occurrenceprimordial
Crystal structure body-centered cubic (bcc) (cI2)
Lattice constant
Body-centered cubic crystal structure for vanadium
a = 302.72 pm (at 20 °C)[3]
Thermal expansion8.4 µm/(m⋅K) (at 25 °C)
Thermal conductivity30.7 W/(m⋅K)
Electrical resistivity197 nΩ⋅m (at 20 °C)
Magnetic orderingparamagnetic
Molar magnetic susceptibility+255.0×10−6 cm3/mol (298 K)[4]
Young's modulus128 GPa
Shear modulus47 GPa
Bulk modulus160 GPa
Speed of sound thin rod4560 m/s (at 20 °C)
Poisson ratio0.37
Mohs hardness6.7
Vickers hardness628–640 MPa
Brinell hardness600–742 MPa
CAS Number7440-62-2
DiscoveryAndrés Manuel del Río[5] (1801)
First isolationHenry Enfield Roscoe (1867)
Named byNils Gabriel Sefström (1830)
Isotopes of vanadium
Main isotopes Decay
abun­dance half-life (t1/2) mode pro­duct
48V synth 16 d β+ 48Ti
49V synth 330 d ε 49Ti
50V 0.25% 2.71×1017 y β+ 50Ti
51V 99.8% stable
 Category: Vanadium
| references

Spanish-Mexican scientist Andrés Manuel del Río discovered compounds of vanadium in 1801 by analyzing a new lead-bearing mineral he called "brown lead". Though he initially presumed its qualities were due to the presence of a new element, he was later erroneously convinced by French chemist Hippolyte Victor Collet-Descotils that the element was just chromium. Then in 1830, Nils Gabriel Sefström generated chlorides of vanadium, thus proving there was a new element, and named it "vanadium" after the Scandinavian goddess of beauty and fertility, Vanadís (Freyja). The name was based on the wide range of colors found in vanadium compounds. Del Rio's lead mineral was ultimately named vanadinite for its vanadium content. In 1867, Henry Enfield Roscoe obtained the pure element.

Vanadium occurs naturally in about 65 minerals and fossil fuel deposits. It is produced in China and Russia from steel smelter slag. Other countries produce it either from magnetite directly, flue dust of heavy oil, or as a byproduct of uranium mining. It is mainly used to produce specialty steel alloys such as high-speed tool steels, and some aluminium alloys. The most important industrial vanadium compound, vanadium pentoxide, is used as a catalyst for the production of sulfuric acid. The vanadium redox battery for energy storage may be an important application in the future.

Large amounts of vanadium ions are found in a few organisms, possibly as a toxin. The oxide and some other salts of vanadium have moderate toxicity. Particularly in the ocean, vanadium is used by some life forms as an active center of enzymes, such as the vanadium bromoperoxidase of some ocean algae.


Vanadium was discovered in Mexico in 1801 by the Spanish mineralogist Andrés Manuel del Río. Del Río extracted the element from a sample of Mexican "brown lead" ore, later named vanadinite. He found that its salts exhibit a wide variety of colors, and as a result, he named the element panchromium (Greek: παγχρώμιο "all colors"). Later, del Río renamed the element erythronium (Greek: ερυθρός "red") because most of the salts turned red upon heating. In 1805, French chemist Hippolyte Victor Collet-Descotils, backed by del Río's friend Baron Alexander von Humboldt, incorrectly declared that del Río's new element was an impure sample of chromium. Del Río accepted Collet-Descotils' statement and retracted his claim.[6]

In 1831 Swedish chemist Nils Gabriel Sefström rediscovered the element in a new oxide he found while working with iron ores. Later that year, Friedrich Wöhler confirmed that this element was identical to that found by del Río and hence confirmed del Río's earlier work.[7] Sefström chose a name beginning with V, which had not yet been assigned to any element. He called the element vanadium after Old Norse Vanadís (another name for the Norse Vanir goddess Freyja, whose attributes include beauty and fertility), because of the many beautifully colored chemical compounds it produces.[7] On learning of Wöhler's findings, del Río began to passionately argue that his old claim be recognized, but the element kept the name vanadium.[8] In 1831, the geologist George William Featherstonhaugh suggested that vanadium should be renamed "rionium" after del Río, but this suggestion was not followed.[9]

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The Model T used vanadium steel in its chassis.

As vanadium is usually found combined with other elements, the isolation of vanadium metal was difficult.[10] In 1831, Berzelius reported the production of the metal, but Henry Enfield Roscoe showed that Berzelius had produced the nitride, vanadium nitride (VN). Roscoe eventually produced the metal in 1867 by reduction of vanadium(II) chloride, VCl2, with hydrogen.[11] In 1927, pure vanadium was produced by reducing vanadium pentoxide with calcium.[12]

The first large-scale industrial use of vanadium was in the steel alloy chassis of the Ford Model T, inspired by French race cars. Vanadium steel allowed reduced weight while increasing tensile strength (c.1905).[13] For the first decade of the 20th century, most vanadium ore were mined by the American Vanadium Company from the Minas Ragra in Peru. Later, the demand for uranium rose, leading to increased mining of that metal's ores. One major uranium ore was carnotite, which also contains vanadium. Thus, vanadium became available as a by-product of uranium production. Eventually, uranium mining began to supply a large share of the demand for vanadium.[14][15]

In 1911, German chemist Martin Henze discovered vanadium in the hemovanadin proteins found in blood cells (or coelomic cells) of Ascidiacea (sea squirts).[16][17]


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Polycrystalline high-purity (99.95%) vanadium cuboids, ebeam remelted and macro-etched

Vanadium is an average-hard, ductile, steel-blue metal. It is electrically conductive and thermally insulating. Vanadium is usually described as "soft", because it is ductile, malleable, and not brittle.[18][19] Vanadium is harder than most metals and steels (see Hardnesses of the elements (data page) and iron). It has good resistance to corrosion and it is stable against alkalis and sulfuric and hydrochloric acids.[20] It is oxidized in air at about 933 K (660 °C, 1220 °F), although an oxide passivation layer forms even at room temperature.[21] It also reacts with hydrogen peroxide.


Naturally occurring vanadium is composed of one stable isotope, 51V, and one radioactive isotope, 50V. The latter has a half-life of 2.71×1017 years and a natural abundance of 0.25%. 51V has a nuclear spin of 72, which is useful for NMR spectroscopy.[22] Twenty-four artificial radioisotopes have been characterized, ranging in mass number from 40 to 65. The most stable of these isotopes are 49V with a half-life of 330 days, and 48V with a half-life of 16.0 days. The remaining radioactive isotopes have half-lives shorter than an hour, most below 10 seconds. At least four isotopes have metastable excited states.[23] Electron capture is the main decay mode for isotopes lighter than 51V. For the heavier ones, the most common mode is beta decay.[24] The electron capture reactions lead to the formation of element 22 (titanium) isotopes, while beta decay leads to element 24 (chromium) isotopes.


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From left: [V(H2O)6]2+ (lilac), [V(H2O)6]3+ (green), [VO(H2O)5]2+ (blue) and [VO(H2O)5]3+ (yellow)

The chemistry of vanadium is noteworthy for the accessibility of the four adjacent oxidation states 2–5. In an aqueous solution, vanadium forms metal aquo complexes of which the colors are lilac [V(H2O)6]2+, green [V(H2O)6]3+, blue [VO(H2O)5]2+, yellow-orange oxides [VO(H2O)5]3+, the formula for which depends on pH. Vanadium(II) compounds are reducing agents, and vanadium(V) compounds are oxidizing agents. Vanadium(IV) compounds often exist as vanadyl derivatives, which contain the VO2+ center.[20]

Ammonium vanadate(V) (NH4VO3) can be successively reduced with elemental zinc to obtain the different colors of vanadium in these four oxidation states. Lower oxidation states occur in compounds such as V(CO)6, [V(CO)
and substituted derivatives.[20]

Vanadium pentoxide is a commercially important catalyst for the production of sulfuric acid, a reaction that exploits the ability of vanadium oxides to undergo redox reactions.[20]

The vanadium redox battery utilizes all four oxidation states: one electrode uses the +5/+4 couple and the other uses the +3/+2 couple. Conversion of these oxidation states is illustrated by the reduction of a strongly acidic solution of a vanadium(V) compound with zinc dust or amalgam. The initial yellow color characteristic of the pervanadyl ion [VO2(H2O)4]+ is replaced by the blue color of [VO(H2O)5]2+, followed by the green color of [V(H2O)6]3+ and then the violet color of [V(H2O)6]2+.[20] Another potential vanadium battery based on VB2 uses multiple oxidation state to allow for 11 electrons to be released per VB2, giving it higher energy capacity by order of compared to Li-ion and gasoline per unit volume.[25] VB2 batteries can be further enhanced as air batteries, allowing for even higher energy density and lower weight than lithium battery or gasoline, even though recharging remains a challenge. [25]


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The decavanadate structure

In an aqueous solution, vanadium(V) forms an extensive family of oxyanions as established by 51V NMR spectroscopy.[22] The interrelationships in this family are described by the predominance diagram, which shows at least 11 species, depending on pH and concentration.[26] The tetrahedral orthovanadate ion, VO3−
, is the principal species present at pH 12–14. Similar in size and charge to phosphorus(V), vanadium(V) also parallels its chemistry and crystallography. Orthovanadate VO3−
is used in protein crystallography[27] to study the biochemistry of phosphate.[28] Besides that, this anion also has been shown to interact with the activity of some specific enzymes.[29][30] The tetrathiovanadate [VS4]3− is analogous to the orthovanadate ion.[31]

At lower pH values, the monomer [HVO4]2− and dimer [V2O7]4− are formed, with the monomer predominant at a vanadium concentration of less than c. 10−2M (pV > 2, where pV is equal to the minus value of the logarithm of the total vanadium concentration/M). The formation of the divanadate ion is analogous to the formation of the dichromate ion.[32][33] As the pH is reduced, further protonation and condensation to polyvanadates occur: at pH 4–6 [H2VO4] is predominant at pV greater than ca. 4, while at higher concentrations trimers and tetramers are formed.[34] Between pH 2–4 decavanadate predominates, its formation from orthovanadate is represented by this condensation reaction:

10 [VO4]3− + 24 H+ → [V10O28]6− + 12 H2O
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Vanadium crystal

In decavanadate, each V(V) center is surrounded by six oxide ligands.[20] Vanadic acid, H3VO4, exists only at very low concentrations because protonation of the tetrahedral species [H2VO4] results in the preferential formation of the octahedral [VO2(H2O)4]+ species.[35] In strongly acidic solutions, pH < 2, [VO2(H2O)4]+ is the predominant species, while the oxide V2O5 precipitates from solution at high concentrations. The oxide is formally the acid anhydride of vanadic acid. The structures of many vanadate compounds have been determined by X-ray crystallography.

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The Pourbaix diagram for vanadium in water, which shows the redox potentials between various vanadium species in different oxidation states[36]

Vanadium(V) forms various peroxo complexes, most notably in the active site of the vanadium-containing bromoperoxidase enzymes. The species VO(O2)(H2O)4+ is stable in acidic solutions. In alkaline solutions, species with 2, 3 and 4 peroxide groups are known; the last forms violet salts with the formula M3V(O2)4 nH2O (M= Li, Na, etc.), in which the vanadium has an 8-coordinate dodecahedral structure.[37][38]

Halide derivatives

Twelve binary halides, compounds with the formula VXn (n=2..5), are known.[39] VI4, VCl5, VBr5, and VI5 do not exist or are extremely unstable. In combination with other reagents, VCl4 is used as a catalyst for the polymerization of dienes. Like all binary halides, those of vanadium are Lewis acidic, especially those of V(IV) and V(V).[39] Many of the halides form octahedral complexes with the formula VXnL6−n (X= halide; L= other ligand).

Many vanadium oxyhalides (formula VOmXn) are known.[40] The oxytrichloride and oxytrifluoride (VOCl3 and VOF3) are the most widely studied. Akin to POCl3, they are volatile,[41] adopt tetrahedral structures in the gas phase, and are Lewis acidic.[42]

Coordination compounds

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A ball-and-stick model of VO(O2C5H7)2

Complexes of vanadium(II) and (III) are reducing, while those of V(IV) and V(V) are oxidants. The vanadium ion is rather large and some complexes achieve coordination numbers greater than 6, as is the case in [V(CN)7]4−. Oxovanadium(V) also forms 7 coordinate coordination complexes with tetradentate ligands and peroxides and these complexes are used for oxidative brominations and thioether oxidations. The coordination chemistry of V4+ is dominated by the vanadyl center, VO2+, which binds four other ligands strongly and one weakly (the one trans to the vanadyl center). An example is vanadyl acetylacetonate (V(O)(O2C5H7)2). In this complex, the vanadium is 5-coordinate, distorted square pyramidal, meaning that a sixth ligand, such as pyridine, may be attached, though the association constant of this process is small. Many 5-coordinate vanadyl complexes have a trigonal bipyramidal geometry, such as VOCl2(NMe3)2.[43] The coordination chemistry of V5+ is dominated by the relatively stable dioxovanadium coordination complexes[44] which are often formed by aerial oxidation of the vanadium(IV) precursors indicating the stability of the +5 oxidation state and ease of interconversion between the +4 and +5 states.[45]

Organometallic compounds

The organometallic chemistry of vanadium is welldeveloped. Vanadocene dichloride is a versatile starting reagent and has applications in organic chemistry.[46] Vanadium carbonyl, V(CO)6, is a rare example of a paramagnetic metal carbonyl. Reduction yields V(CO)
(isoelectronic with Cr(CO)6), which may be further reduced with sodium in liquid ammonia to yield V(CO)3−
(isoelectronic with Fe(CO)5).[47][48]


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Vanadium is the 20th most abundant element in the Earth's crust;[49] metallic vanadium is rare in nature (known as native vanadium),[50][51] having been found among fumaroles of the Colima Volcano, but vanadium compounds occur naturally in about 65 different minerals.

Vanadium began to be used in the manufacture of special steels in 1896. At that time, very few deposits of vanadium ores were known. Between 1899 and 1906, the main deposits exploited were the mines of Santa Marta de los Barros (Badajoz), Spain. Vanadinite was extracted from these mines.[52] At the beginning of the 20th century, a large deposit of vanadium ore was discovered in the Minas Ragra vanadium mine near Junín, Cerro de Pasco, Peru.[53][54][55] For several years this patrónite (VS4)[56] deposit was an economically significant source for vanadium ore. In 1920 roughly two-thirds of the worldwide production was supplied by the mine in Peru.[57] With the production of uranium in the 1910s and 1920s from carnotite (K2(UO2)2(VO4)2·3H2O) vanadium became available as a side product of uranium production. Vanadinite (Pb5(VO4)3Cl) and other vanadium bearing minerals are only mined in exceptional cases. With the rising demand, much of the world's vanadium production is now sourced from vanadium-bearing magnetite found in ultramafic gabbro bodies. If this titanomagnetite is used to produce iron, most of the vanadium goes to the slag and is extracted from it.[58][55]

Vanadium is mined mostly in China, South Africa and eastern Russia. In 2022 these three countries mined more than 96% of the 100,000 tons of produced vanadium, with China providing 70%.[59]

Fumaroles of Colima are known of being vanadium-rich, depositing other vanadium minerals, that include shcherbinaite (V2O5) and colimaite (K3VS4).[60][61][62]

Vanadium is also present in bauxite and deposits of crude oil, coal, oil shale, and tar sands. In crude oil, concentrations up to 1200 ppm have been reported. When such oil products are burned, traces of vanadium may cause corrosion in engines and boilers.[63] An estimated 110,000 tons of vanadium per year are released into the atmosphere by burning fossil fuels.[64] Black shales are also a potential source of vanadium. During WW II some vanadium was extracted from alum shales in the south of Sweden.[65]

In the universe, the cosmic abundance of vanadium is 0.0001%, making the element nearly as common as copper or zinc.[66] Vanadium is detected spectroscopically in light from the Sun and sometimes in the light from other stars.[67] The vanadyl ion is also abundant in seawater, having an average concentration of 30 nM (1.5 mg/m3).[66] Some mineral water springs also contain the ion in high concentrations. For example, springs near Mount Fuji contain as much as 54 μg per liter.[66]


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Vanadium production trend
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Vacuum sublimed vanadium dendritic crystals (99.9%)

Vanadium metal is obtained by a multistep process that begins with roasting crushed ore with NaCl or Na2CO3 at about 850 °C to give sodium metavanadate (NaVO3). An aqueous extract of this solid is acidified to produce "red cake", a polyvanadate salt, which is reduced with calcium metal. As an alternative for small-scale production, vanadium pentoxide is reduced with hydrogen or magnesium. Many other methods are also used, in all of which vanadium is produced as a byproduct of other processes.[68] Purification of vanadium is possible by the crystal bar process developed by Anton Eduard van Arkel and Jan Hendrik de Boer in 1925. It involves the formation of the metal iodide, in this example vanadium(III) iodide, and the subsequent decomposition to yield pure metal:[69]

2 V + 3 I2 2 VI3
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Ferrovanadium chunks

Most vanadium is used as a steel alloy called ferrovanadium. Ferrovanadium is produced directly by reducing a mixture of vanadium oxide, iron oxides and iron in an electric furnace. The vanadium ends up in pig iron produced from vanadium-bearing magnetite. Depending on the ore used, the slag contains up to 25% of vanadium.[68]


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Tool made from vanadium steel


Approximately 85% of the vanadium produced is used as ferrovanadium or as a steel additive.[68] The considerable increase of strength in steel containing small amounts of vanadium was discovered in the early 20th century. Vanadium forms stable nitrides and carbides, resulting in a significant increase in the strength of steel.[70] From that time on, vanadium steel was used for applications in axles, bicycle frames, crankshafts, gears, and other critical components. There are two groups of vanadium steel alloys. Vanadium high-carbon steel alloys contain 0.15–0.25% vanadium, and high-speed tool steels (HSS) have a vanadium content of 1–5%. For high-speed tool steels, a hardness above HRC 60 can be achieved. HSS steel is used in surgical instruments and tools.[71] Powder-metallurgic alloys contain up to 18% percent vanadium. The high content of vanadium carbides in those alloys increases wear resistance significantly. One application for those alloys is tools and knives.[72]

Vanadium stabilizes the beta form of titanium and increases the strength and temperature stability of titanium. Mixed with aluminium in titanium alloys, it is used in jet engines, high-speed airframes and dental implants. The most common alloy for seamless tubing is Titanium 3/2.5 containing 2.5% vanadium, the titanium alloy of choice in the aerospace, defense, and bicycle industries.[73] Another common alloy, primarily produced in sheets, is Titanium 6AL-4V, a titanium alloy with 6% aluminium and 4% vanadium.[74]

Several vanadium alloys show superconducting behavior. The first A15 phase superconductor was a vanadium compound, V3Si, which was discovered in 1952.[75] Vanadium-gallium tape is used in superconducting magnets (17.5 teslas or 175,000 gauss). The structure of the superconducting A15 phase of V3Ga is similar to that of the more common Nb3Sn and Nb3Ti.[76]

It has been found that a small amount, 40 to 270 ppm, of vanadium in Wootz steel significantly improved the strength of the product, and gave it the distinctive patterning. The source of the vanadium in the original Wootz steel ingots remains unknown.[77]

Vanadium can be used as a substitute for molybdenum in armor steel, though the alloy produced is far more brittle and prone to spalling on non-penetrating impacts.[78] The Third Reich was one of the most prominent users of such alloys, in armored vehicles like Tiger II or Jagdtiger.[79]


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Vanadium(V) oxide is a catalyst in the contact process for producing sulfuric acid.

Vanadium compounds are used extensively as catalysts;[80] Vanadium pentoxide V2O5, is used as a catalyst in manufacturing sulfuric acid by the contact process[81] In this process sulfur dioxide (SO
) is oxidized to the trioxide (SO
):[20] In this redox reaction, sulfur is oxidized from +4 to +6, and vanadium is reduced from +5 to +4:

V2O5 + SO2 → 2 VO2 + SO3

The catalyst is regenerated by oxidation with air:

4 VO2 + O2 → 2 V2O5

Similar oxidations are used in the production of maleic anhydride:

C4H10 + 3.5 O2 → C4H2O3 + 4 H2O

Phthalic anhydride and several other bulk organic compounds are produced similarly. These green chemistry processes convert inexpensive feedstocks to highly functionalized, versatile intermediates.[82][83]

Vanadium is an important component of mixed metal oxide catalysts used in the oxidation of propane and propylene to acrolein, acrylic acid or the ammoxidation of propylene to acrylonitrile.[84]

Other uses

The vanadium redox battery, a type of flow battery, is an electrochemical cell consisting of aqueous vanadium ions in different oxidation states.[85][86] Batteries of this type were first proposed in the 1930s and developed commercially from the 1980s onwards. Cells use +5 and +2 formal oxidization state ions. Vanadium redox batteries are used commercially for grid energy storage.[87]

Vanadate can be used for protecting steel against rust and corrosion by conversion coating.[88] Vanadium foil is used in cladding titanium to steel because it is compatible with both iron and titanium.[89] The moderate thermal neutron-capture cross-section and the short half-life of the isotopes produced by neutron capture makes vanadium a suitable material for the inner structure of a fusion reactor.[90][91]

Vanadium can be added in small quantities < 5% to LFP battery cathodes to increase ionic conductivity.[92]


Lithium vanadium oxide has been proposed for use as a high energy density anode for lithium-ion batteries, at 745 Wh/L when paired with a lithium cobalt oxide cathode.[93] Vanadium phosphates have been proposed as the cathode in the lithium vanadium phosphate battery, another type of lithium-ion battery.[94]