KO2

KO2, or potassium superoxide, is an inorganic compound that consists of potassium cations (K+) and superoxide anions (O2−). The superoxide anion carries unpaired electrons, giving KO2 paramagnetism and strong oxidizing properties. It appears as a white to pale yellow crystalline solid that is hygroscopic and moisture sensitive.

In air or water it reacts vigorously. Upon exposure to moisture, KO2 releases oxygen gas and forms potassium hydroxide; reactions may also involve hydrogen peroxide as an intermediate. It readily hydrolyzes in water.

KO2 can react with carbon dioxide: 2 KO2 + CO2 → K2CO3 + O2, a reaction exploited for carbon dioxide scrubbing in enclosed environments. It also serves as an oxygen source in chemical oxygen generators used in submarines and spacecraft.

Preparation: KO2 is produced commercially by controlled oxidation of potassium salts with oxygen at elevated temperature, or by conversion from potassium peroxide under oxidizing conditions. It is typically stored under dry, inert atmosphere to avoid moisture uptake.

Safety: KO2 is a powerful oxidizer and can react violently with organic materials or reducing agents. It can decompose with heat, releasing oxygen; contact with moisture or acids can cause fires or explosions. Proper handling requires dry, noncombustible storage and avoidance of contaminants.