부산대학교 도서관

The superposition principle of currents in a solar cell states that the current flowing in an illuminated device subject to a forward bias V is given by the algebraic sum of the short circuit photocurrent and the current which would flow at bias V in the dark. We investigate this principle here in detail for the case of semiconductor-electrolyte solar cells. However, the results are also applicable to Schottky-barrier solar cells. It is concluded that the density of photoexcitable surface states and the surface transfer velocity for minority carriers from the semiconductor into the electrolyte are two important parameters that determine the validity of applying the superposition principle as well as in determining the current-voltage (J-V) characteristic of the device.