What is the recombination factor?
(Edit Q&A) A: When a sufficiently energetic photon has been absorbed by a semiconductor, and an electron-electron hole pair created, sometimes the pair inadvertently recombine before they can be drawn off to an external circuit. This may happen because of defects in the crystalline structure, frequently on the surfaces or at junctions. This inadvertent recombination has the effect of lowering efficiency. It is a property of the purity and geometry of a photovoltaic material. • Q: What is quantum efficiency? (Edit Q&A) A: Quantum efficiency is a ratio of the number of photons at a specific wavelength absorbed by a photovoltaic device compared to the total number incident upon the device. Note that the term is used analogously in astronomy to quantify generic photodetectors. For the measurement a monochromatic light light source is used. The result is not a single number, as in the case of standard AM1.5 efficiency, but a 2D graph of efficiency versus wavelength of the light source. A kn
When a sufficiently energetic photon has been absorbed by a semiconductor, and an electron-electron hole pair created, sometimes the pair inadvertently recombine before they can be drawn off to an external circuit. This may happen because of defects in the crystalline structure, frequently on the surfaces or at junctions. This inadvertent recombination has the effect of lowering efficiency. It is a property of the purity and geometry of a photovoltaic material. 10E) What is diffusion length? Diffusion length is the average distance that a minority carrier (an electron in p-type; a hole in n-type) moves in a semiconductor, before it recombines. See also: • What is the recombination factor? 10F) How do band gap and the solar spectrum affect efficiency? Consider the straightforward fact that solar cells are only able to capture photons with an energy greater than or equal to their band gap. This statement is another way of saying that all of the photons with energy less than the band gap
When a sufficiently energetic photon has been absorbed by a semiconductor, and an electron-electron hole pair created, sometimes the pair inadvertently recombine before they can be drawn off to an external circuit. This may happen because of defects in the crystalline structure, frequently on the surfaces or at junctions. This inadvertent recombination has the effect of lowering efficiency. It is a property of the purity and geometry of a photovoltaic material.
