Caesium peroxide

Caesium peroxide or cesium peroxide is an <a href="/facts/Inorganic_compound/TfFfzxSz">inorganic compound</a> of <a href="/facts/Caesium/dXKN1S5k">caesium</a> and <a href="/facts/Oxygen/acyn6o8r">oxygen</a> with the <a href="/facts/Chemical_formula/hghUtthl">chemical formula</a> <a href="/facts/Caesium/dXKN1S5k">Cs</a>2<a href="/facts/Oxygen/acyn6o8r">O</a>2. It can be formed from caesium metal by adding a stoichiometric amount in <a href="/facts/Ammonia/MtLtJFtz">ammonia solution</a>, or oxidizing the solid metal directly.

2 Cs + O2 → Cs2O2
It can also be formed by the thermal decomposition of <a href="/facts/Caesium_superoxide/YY06P2Pj">caesium superoxide</a>:

2 CsO2 → Cs2O2 + O2
Upon heating until 650 °C, the compound will decompose to <a href="/facts/Caesium_monoxide/uBCmopGC">caesium monoxide</a> and <a href="/facts/Atomic_oxygen/UVNYnKUQ">atomic oxygen</a>:

Cs2O2 → Cs2O + [O]
Caesium peroxide shows a <a href="/facts/Raman_spectroscopy/XY063k29">Raman</a> vibration at 743 cm−1, due to the presence of the <a href="/facts/Peroxide/VMU8y4xB">peroxide</a> ions. The compound is often used as a coating for <a href="/facts/Photocathode/XPcNlAjs">photocathodes</a>, due to its low <a href="/facts/Work_function/VHaHTyXg">work function</a>.

Caesium peroxide open-in-new

Caesium peroxide