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Question
Why are Si and GaAs preferred materials for solar cells?
Solution
(ii) The energy for the maximum intensity of the solar radiation is nearly equals to 1.5 eV. So, to obtain the photo excitation the energy radiation (h \[\nu\]) must be greater than the energy band gap (Eg). semiconductors with band gaps close to 1.5 eV are ideal materials for the fabrication of solar cells. Since Si and GaAs have band gaps of 1.1 eV and 1.53 eV, they are preferred for making solar cells.
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