PHOTOELECTROLYSIS OF WATER

In the photoelectrolysis of water, hydrogen is produced from water using sunlight and specialised semiconductors similar to the ones used in a photovoltaic cell. The light energy is then used to dissociate water molecules into hydrogen and oxygen directly. In photovoltaic, the principle is such that two semiconductors (p-type and n-type) are joined to form a p–n junction. The collection of light-generated carriers by the p-n junction causes a movement of electrons to the n-type side and holes to the p-type side of the junction. Under short circuit conditions, there is no charge build-up, as the carriers exit the device as light-generated current. ¹⁵ For photoelectrolysis, the semiconductor is immersed in a water-based electrolyte, where instead of electricity production the solar energy is used for the water-splitting process.[1]^,[2]

[1] HORČÍK, J. Výroba vodíku s pomocí solárních elektráren [online]. Ekologické bydlení. Available at: http://www.ekobydleni.eu/energie/vyroba-vodiku-s-pomocisolarnich-elektraren