Titanium(III) oxide is the inorganic compound with the formula TiO. A black semiconducting solid, it is prepared by reducing titanium dioxide with titanium metal at 1600 °C.
TiO adopts the AlO (corundum) structure. It is reactive with oxidising agents. At around 200 °C, there is a transition from semiconducting to metallic conducting. Titanium(III) oxide occurs naturally as the extremely rare mineral in the form of tistarite.
Other titanium(III) oxides include LiTiO and LiTiO.