Kupferoxide

Kupferoxide, commonly called copper oxide, refers to inorganic compounds composed of copper and oxygen. The two principal oxides are copper(II) oxide (CuO) and copper(I) oxide (Cu2O). In nature they occur as the minerals tenorite (CuO) and cuprite (Cu2O), and they can also be prepared synthetically.

Copper(II) oxide is a black solid with a monoclinic crystal structure, while copper(I) oxide is a red solid with a cubic cuprite structure. Both oxides are relatively insoluble in water and form copper salts when dissolved in acids. They are p-type semiconductors and have been explored for applications in electronics, catalysis, and sensor technologies.

Production and occurrence: Kupferoxide forms when copper metal is exposed to air at elevated temperatures. At lower temperatures or under reducing conditions, Cu2O is favored, whereas higher temperatures promote the formation of CuO. In ore processing, roasting copper-containing sulfide ores yields CuO, and controlled reduction can convert CuO to Cu2O. Copper oxides can also be obtained by oxidation or reduction of copper hydroxides under suitable conditions.

Reactions and applications: Both oxides react with acids to give copper salts and water. They are used as pigments in ceramics and paints, as catalysts for oxidation processes, and as precursors for other copper compounds. Nanoscale copper oxide materials are investigated for use in photovoltaics, gas sensing, and other electronic applications.

Safety: Copper oxides are irritants to the eyes, skin, and lungs in dusty form. Prolonged exposure or inhalation of dust should be avoided, and proper handling and disposal procedures should be followed.