Cesium photocell

A cesium photocell is an optoelectronic device that converts light energy into electrical energy. When photons of light hit a metal surface, electrons are ejected, and this phenomenon is called the photoelectric effect. Cesium photocells are based on this phenomenon. Cesium has a lower ionization energy than other metals. Therefore, it is the most suitable metal to use for this purpose.

Working principle of the photo cell:

  • Light Absorption: When light strikes the cesium-coated surface of the photocell, the energy from the light is absorbed by the cesium atoms. Cesium coated surface shown as half sphere on the below picture. 
  • Electron Emission: The absorbed energy excites the electrons in the cesium, providing them with enough energy to escape from the metal surface. 
  • Current Generation: The emitted electrons create a flow of electric current, which can be harnessed for various applications.

 

 

Cesium photocell
Cesium photocell