Cobalt phosphate

Cobalt phosphate is the inorganic compound with the formula Co3(PO4)2. It is a commercial inorganic pigment known as cobalt violet. Thin films of this material are water oxidation catalysts. Cobalt phosphate is the inorganic compound with the formula Co3(PO4)2. It is a commercial inorganic pigment known as cobalt violet. Thin films of this material are water oxidation catalysts. The tetrahydrate CoPO4(H2O)4 precipitates as a solid upon mixing aqueous solutions of cobalt(II) and phosphate salts. Upon heating, the tetrahydrate converts to the anhydrous material. According to X-ray crystallography, the anhydrous CoPO4 consists of discrete phosphate (PO3−4) anions that link Co2+ centres. The cobalt ions occupy both octahedral (six-coordinate) and pentacoordinate sites in a 1:2 ratio.