Ahstraet
-The photocurrent us potential characteristics for three different electrolytescmiconducctor junctions, representative of those generally found in semiconductor photoelectrochemistry, arc analyzed in detail using parameters which defme both the semiconductor and the electrolyte. It is shown that, in general, the behaviour of junctions including semiconductors with sufficiently wide energy gapsand large free carriers densities, may be accurately described using the Girrtner model in the potential region which does not include the onset of the photocurrent. In this case, it is the characteristics of the semiconductor which control the photoresponse and the electrolyte does not induce limiting steps in the charge transfer across the interface. If certain restrictive conditions are ful6lled concerning the relative orders of magnitude of the semiconductor space charge region. diffusion length of minority carriers and penetration depth of light into the semiconductor, the value of the flat band potential may be easily determined by plotting i$, vs V and extrapolating to i$, = 0. In the other cases, the relation established by GBrtner between iph and V has been verified provided that the free carriers density be sufficiently large.