The recombination reactions in the dye-sensitized solar cells (DSSCs) are extremely complex since many different recombination paths simultaneously exist. They all effect the open circuit voltage (Voc) vs. illumination intensity (G) dependence. In the literature many contradictive results about the dVoc/dlog(G) gradient exist. In order to resolve the discrepancies we have studied the influence of the thickness of the active layer and temperature dependence along with I3- concentration (c[I3-]) on the dVoc/dlog(G) gradient. The results revealed that the thickness of the active layer has only a small effect on the dVoc/dlog(G) gradient. Contrary, the gradient very strongly depends on the cell temperature (Tc) and c[I3-]. The gradient could be only 60 mV/decade when the c[I3-] and the Tc are low (when the DSSC is diffusion limited) and it could exceed 130 mV/decade at higher c[I3-] and higher Tc (when recombinations prevails). Additionally, the open circuit voltage temperature coefficient (dVoc/dT) of the DSSCs having different c[I3-] has been measured at different G. The absolute value of the dVoc/dT increases with c[I3-] in the electrolyte and with decreasing G which is both associated with a higher probability of the recombinations.
COBISS.SI-ID: 8807508