Using blackbody structure to improve the efficiency of solar cell

Abstract

Today solar power is the most promising new energy source, it is safe, cheap, and abundant. Its total power on the earth reaches per year, and we human only need per year. Solar cell is an essential device that can convert the energy from the sunlight into electricity; however, current solar cell reflects too much sunlight shone thereon, and this is a major factor that lowers its conversion efficiency, which is only about on average. Blackbody is material that can only absorb but never reflect electromagnetic radiation, in nature it is hard to find blackbody material, but a large cavity with only a small hole can be approximately equivalent to a blackbody, and such structure is also applicable to reduce the reflection of current solar cell, using it to modify the anti-reflective layer of a solar cell. By substituting multilayer “non-head” pyramid structures for the “inverted” pyramid structures in the anti-reflective layer of a current solar cell, the reflection can be reduced since the lights shone into the multilayer “non-head” pyramids through their entrances need to be reflected for many times before going out again. This can improve the conversion efficiency of current solar cells a lot.