http://www.planetfunorb.com/direct-solar-energy-definition/
can someone check my solar cells process definition?
Photovoltaic,(photo = light, voltaic = energy) is a process in which photovoltaic cells (solar cells) convert direct sunlight into electricity
Photovoltaic cells are semiconductors that consist of an n-type layer ( silicon doped with phosphorous) on top, and a p-type layer (silicon doped with boron.) on the bottom.
When these two layers are in contact, the extra electrons from the n-type layer will fill the holes on the p-type layers creating an electric field. This electric field caused the electrons from the p-type layers to move over to the n-type layers but can’t get back.
When photons hits the surface of the photovoltaic cells, some of its energy will be absorbed by the electrons of the cells allowing it to escape the atom. These electron then is flow into a current and can be converted into AC electricity and come back to fill the holes in the n-type layer.
is this right? anything i should add or remove?
Looks alright to me.
You may want to mention energy bands. Outer electrons are technically in the Valence band of the semiconductor and in our best models this energy band spreads across the entire lattice; they’re not really associated with a particular atom, so saying an electron escapes an atom (in most cases) isn’t exactly correct – it escapes the energy band.
Say that when the electrons receive energy from photons, they move from the Valence band to the Conduction band, which leaves a ‘hole’ in the Valence band. These charge carriers then move because of the applied field from sticking the n type & p type semiconductors together.
This argument comes from quantum theory which you probably don’t want to go into… wiki has some diagrams though!
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