The most commercially significant form of vanadium is vanadium pentoxide. It is primarily used is in the production of ferrovanadium and as an industrial catalyst for the production of sulfuring acid; it can as function as a mordant or a ceramic pigment. Compounds that contain vanadium in a (+5) oxidation state are used as oxidizing agents in chemical reactions, whereas vanadium(2+) compounds are used as reducing agents. The pentoxide and ammonium metavanadate are both excellent oxidation employed by the chemical industry to produce sulfuric acid, synthetic plastics, and other organic compounds. Some vanadium compounds have applications in the field of medicine such as treatments for diabetes mellitus and nutritional supplements; the isotope 51V is used in nuclear magnetic resonance spectroscopy (NMR spectroscopy). However, all vanadium compounds are considered toxic to humans to some degree, particularly those with vanadium in a higher valence state. Trace amounts of the element exist in foods, the major source of exposure to the general public, but powdered forms of vanadium compounds are particularly hazardous due to the danger of inhalation and the ease with which the lungs absorb soluble vanadium salts.

Its thermal and electrical conductivity and strength is superior to that of titanium, and the majority of its commercial use (~92%) is in the production of alloys. Adding even a small amount of vanadium to steel dramatically increases its tensile strength and hardness, in addition to providing shock and vibration resistance; vanadium steel, also referred to as “tool steel” or “high-speed steel,” is one of the strongest alloys used in armor plates, piston rods, jet engines, cutting tools, and other equipment parts. Vanadium steel is also used in the cores of nuclear reactors due to its resistance to corrosion and high temperatures in addition to vanadium’s excellent thermal neutron-capture cross-section. Ferrovanadium is a similarly strong, shock resistant and corrosion resistant iron alloy produced by reduction of vanadium pentoxide by aluminum or silicon in the presence of iron under an electric arc furnace. Ferrovanadium melts more easily than pure vanadium, and is often used as a master alloy to be added to steel before casting. Common nonferrous vanadium alloys include Titanium 6AL-4V used in aircraft and dental alloys (owing to the natural antibacterial properties of titanium); vanadium foil is also used to clad titanium to steel. Vanadium-silicon (V3Si) is classified as an A15-phase compound, an intermetallic crystalline compound composed of a transition metal (“A”) and any other element (“B”) with the formula A3B; V3Si was the first such compound discovered to exhibit superconductivity in 1953. Additionally, mixing vanadium and gallium in the ratio V3Ga yields a superconducting alloy used in the coils of superconducting electromagnets, either in the form of a wire or tape.

The role of vanadium in advanced and emerging technologies is increasing due to the unique properties of its compounds. In particular, vanadium redox (or flow) batteries have gained attention in recent years as viable alternatives to the dominant lithium-ion technology currently in use. These rechargeable batteries store energy via continuously recyclable aqueous solutions of vanadium redox couples in both electrodes, eliminating the risk of cross-contamination of the electrolyte and yielding a low cost, high-efficiency energy source that has been investigated for potential use in hybrid and electric vehicles. Two-dimensional nanosheets of vanadium pentoxide have demonstrated favorable properties that could lead to their use as electrodes in supercapacitors.Vanadium dioxide has also gained attention for its unique properties. It is one of the few known materials that undergoes a metal-insulator transition: acting as an insulator at low temperatures, the material rearranges its electrons in an abrupt shift (taking only 10-trillionth of a second) to act like a conductor at 67 degrees Celsius. At 65 degrees, it enters a solid-state triple point--the first material in which researchers have ever accurately pinpointed. Some experiments into the uses of vanadium dioxide include the work of researchers at the Lawrence Berkeley National Laboratory, who used vanadium dioxide to fabricate a micro-sized artificial muscle-motor that exhibited extremely high power density and resilience. Thin ribbons of vanadium dioxide alternating with graphene have shown to be a highly efficient cathode material for lithium-ion batteries that could significantly increase power and energy density, and it has also been investigated as a metamaterial.