Cadmium oxide is an inorganic compound with the formula CdO. It is one of the main precursors to other cadmium compounds. It crystallizes in a cubic rocksalt lattice like sodium chloride, with octahedral cation and anion centers. It occurs naturally as the rare mineral monteponite. Cadmium oxide can be found as a colorless amorphous powder or as brown or red crystals. Cadmium oxide is an n-type semiconductor with a band gap of 2.18 eV (2.31 eV) at room temperature (298 K).
Molar mass：128.413 g·mol−1
Appearance：colorless powder (alpha form)
red-brown crystal (beta form)
6.95 g/cm3 (amorphous) solid.
Melting point：900–1,000 °C (1,650–1,830 °F; 1,170–1,270 K)
decomposition of amorphous form
Boiling point：1,559 °C (2,838 °F; 1,832 K) sublimation
Solubility in water：4.8 mg/L (18 °C)
Solubility：soluble in dilute acid
slowly soluble in ammonium salts
insoluble in alkalies
Crystal structure: cubic, cF8
Cadmium oxide is used in cadmium plating baths, electrodes for storage batteries, cadmium salts, catalyst, ceramic glazes, phosphors, and nematocide. Major uses for cadmium oxide are as an ingredient for electroplating baths, and in pigments.