Anatase

Anatase is a naturally occurring crystalline form of titanium dioxide, distinguished by its tetragonal crystal structure. It is one of three major TiO₂ polymorphs, alongside rutile and brookite.

Titanium dioxide: Titanium dioxide is an inorganic compound of titanium and oxygen with the formula TiO₂. Anatase is one crystalline form of this compound.
Rutile: Rutile is a tetragonal crystalline form of titanium dioxide and its most stable bulk polymorph. Rutile shares anatase's composition but has a different structure and greater bulk stability.
Photocatalysis: Photocatalysis uses light-activated materials to accelerate chemical reactions. Anatase surfaces can drive reactions after absorbing ultraviolet light.
Photocatalytic self-cleaning surfaces: Photocatalytic self-cleaning surfaces use light-activated coatings to break down organic contaminants or improve water spreading. Anatase coatings can help decompose organic grime under ultraviolet illumination.
Polymorphism (materials science): Polymorphism is the ability of a solid material to form multiple crystal structures. Anatase, rutile, and brookite are polymorphs with different atomic arrangements.
Brookite: Brookite is an orthorhombic crystalline form of titanium dioxide. Brookite is the third major TiO₂ polymorph and differs from anatase in crystal symmetry.
Band gap: A band gap is the energy range separating a solid's valence and conduction electronic bands. Anatase's band gap sets the threshold for exciting electrons with light.
Dye-sensitized solar cell: A dye-sensitized solar cell converts light into electricity using a dye attached to a porous semiconductor electrode. Nanocrystalline anatase commonly forms the porous electron-collecting electrode.
Tetragonal crystal system: The tetragonal crystal system has three mutually perpendicular axes, with two equal lengths and one different length. Anatase's crystal structure belongs to this system.
TiO₂-B: TiO₂-B is a metastable monoclinic polymorph of titanium dioxide. This less common polymorph provides another structural alternative to anatase.

Linked from 6 pages