The main principle of photovoltaic power generation is the photoelectric effect of semiconductor. When a photon irradiates a metal, its energy can be absorbed by a certain electron in the metal. The energy absorbed by the electron is large enough to overcome the internal gravity of the metal and escape from the metal surface to become photoelectron. Silicon atom has four outer electrons. If five outer electrons such as phosphorus atom are added into pure silicon, it will become n-type semiconductor; if three outer electrons such as boron atom are added into pure silicon, it will form p-type semiconductor. When p-type and n-type are combined, the contact surface will form potential difference and become solar cell. When the sunlight hits the p-n junction, the hole moves from the p-polar region to the N-polar region, and the electron moves from the N-polar region to the p-polar region, forming a current.
Post time: Jul-12-2021
