Analytical extraction of the single-diode model parameters for macro-porous silicon-based dye-sensitized solar cells using Lambert W-function

In this work, based on the Lambert W-function and a single-diode five-parameter model, the electrical characteristics of the macro-porous silicon-based dye-sensitized solar cell (PSi-DSSC) and its photovoltaic performance are investigated. As the first step, PSi-DSSCs with different silicon porosities were formed and characterized. In the next step, using the equivalent circuit of the single diode model, the derivation of DSSC parameters from a single I-V curve under only one constant illumination level was carried out. It was found that the I-V curves rebuilt with the extracted parameters are in good agreement with the original experimental I-V curves. The influence of silicon porosity upon the five equivalent circuit parameters, including the reverse diode saturation current I-0, the photocurrent I-ph, the series resistance R-s, the shunt resistance R-sh, and the ideality factor n, was examined. It was demonstrated that the higher optical absorption coefficient of the porous silicon structure increases I-ph and that providing a larger contact area for electrolytes with dye-adsorbed TiO2 is effective in accelerating the rate of the oxidized dye reduction by I- and of decreasing R-s. R-sh was also increased by reduction of the chance of charge recombination across the TiO2/dye/electrolyte junctions. An increase in the porosity of the silicon photoanode to 65% demonstrated improved cell performance with similar to 32%, similar to 3.7%, and similar to 6.3% enhancement in the short current circuit (I-sc), open-circuit voltage (V-oc), and fill factor (FF), respectively. Finally, the highest efficiency value of 5.45% was achieved for PSi-DSSC (sample 4), which is about 45% higher than 3.76% of the standard DSSC (sample 1).

Automated summary

In this study, the electrical characteristics and photovoltaic performance of a macro-porous silicon-based dye-sensitized solar cell (PSi-DSSC) were investigated using the Lambert W-function and a single-diode five-parameter model. The results showed that increasing the silicon porosity improved the cell performance.