Experiment
The DSSC under test is fabricated from a fluorine-doped SnO2 (FTO) conducting glass, ruthenium (II)
dye (N719) sensitized TiO2 nanoparticles, an iodide-triiodide electrolyte, and a Pt counter electrode. It has
an area of 0.6 cm2. Under 1 sun, air mass 1.5 illumination and standard test conditions, the DSSC shows a
short circuit current density (JSC) of 0.72 mA/cm2 and an open circuit voltage (VOC) of 0.49 V.
The DSSC is investigated under dark conditions, at room temperature, using a FRA (impedance gain -
phase analyzer, Solartron 1260) under both forward and reverse biases of 0.2, 0.3, and 0.4 V. The
amplitude of a small AC signal superimposing on the DC bias is about 10% of the bias level. The AC
signal is in the frequency range of 0.01 Hz to 200 kHz. Frequency response measurement results are
plotted as impedance loci in the complex plan, and separate magnitude and argument plots.