Photovoltaic effect

He explained his discovery in Comptes rendus de l'Académie des sciences, "the production of an electric current when two plates of platinum or gold immersed in an acid, neutral, or alkaline solution are exposed in an uneven way to solar radiation.

"[2] The first solar cell, consisting of a layer of selenium covered with a thin film of gold, was experimented by Charles Fritts in 1884, but it had a very poor efficiency.

In addition to the direct photovoltaic excitation of free electrons, an electric current can also arise through the Seebeck effect.

[5] The AC PV effect is based on the capacitive model that the current strongly depends on the frequency of the chopper.

The AC PV effect is suggested to be a result of the relative shift and realignment between the quasi-Fermi levels of the semiconductors adjacent to the junction/interface under the nonequilibrium conditions.

The organic solar cell, which the materials have no initial carrier concentration, does not have the AC PV effect.

However, the temperature T of the p–n junction also influences the main electrical parameters: the short-circuit current ISC, the open-circuit voltage VOC, and the maximum power Pmax.

The values of these parameters can be found in any PV module data sheet; they are the following: – β Coefficient of variation of VOC with respect to T, given by ∂VOC/∂T.

It is found that except for the DC output generated by the conventional PV effect based on a p–n junction, AC current is also produced when a flashing light is illuminated at the interface.

Mafate Marla solar panel
Band diagram illustration of the photovoltaic effect. Photons give their energy to electrons in the depletion or quasi-neutral regions. These move from the valence band to the conduction band . Depending on the location, electrons and holes are accelerated by drift electric field E drift , which gives generation photocurrent , or by scattering electric field E scatt , which gives scattering photocurrent. [ 4 ]