Figure 8.
Result of drift-diffusion simulations of MAPI solar cells showing (a) power conversion efficiency and (b) open-circuit voltage Voc as a function of the built-in voltage for different values of the surface recombination velocity S for minority carriers at front and back contact. For every value of S, there is an optimum built-in voltage, because for lower built-in voltages, surface recombination increases and for higher built-in voltages Auger recombination increases. (Online version in colour.)