However, the most familiar form of the photovoltaic effect uses solid-state devices, mainly in photodiodes. When sunlight or other sufficiently energetic light is incident upon the photodiode, the electrons present in the valence band absorb energy and, being excited, jump to the conduction band and become free. The photovoltaic effect is the generation of voltage and in a material upon exposure to. It is a phenomenon. The photovoltaic effect is closely related to the In addition to the direct photovoltaic excitation of free electrons, an electric current can also arise through the. When a conductive or semiconductive material is heated by absorption of electromagnetic radiation, the heating can lead to. • • • The first demonstration of the photovoltaic effect, by in 1839, used an electrochemical cell. He explained his discovery in, "the production of an electric current when two plates of platinum or gold. In most photovoltaic applications, the source is sunlight, and the devices are called. In the case of a semiconductor p–n (diode) junction solar cell, illuminating the material creates an electric current because excited electrons and the. The first demonstration of the photovoltaic effect, by in 1839, used an electrochemical cell. He explained his discovery in, "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.".