[6] Upon heating, the hexagonal form undergoes a transition into a phase of unknown symmetry at 512 °C.
[8] Commercially, sodium peroxide is produced from the elements in a two-stage process.
[10] It may also be produced by passing ozone gas over solid sodium iodide inside a platinum or palladium tube.
The platinum or palladium catalyzes the reaction and is not attacked by the sodium peroxide.
The octahydrate can be produced by treating sodium hydroxide with hydrogen peroxide.