Increasing the Efficiency of a Dye-Sensitized Solid-State Solar Cell by Iodine Elimination Process in Hole Conductor Material

The use of silicon in photovoltaics are popular these days. Besides the use of silicon, the use of titanium dioxide as an n-type semiconductor material is trending in the emerging dye-sensitized solar cells due to its low cost, nontoxicity and ease in preparation when compared to silicon. The objective of this research is to find avenues to enhance the efficiency of a dye-sensitized solid state solar cell, fabricated using D-149 and N-719 dyes as sensitizers and excess iodine-eliminated cuprous iodide hole conductor. P-25 Degussa titanium dioxide in a titanium dioxide colloidal suspension was used to deposit titanium dioxide thin films with a thickness less than 20 µm on fluorine-doped tin oxide glasses. Titanium dioxide films were then immersed in the dye solution for 12 h to enable dye adsorption. Acetonitrile solution containing refined copper powder treated cuprous iodide was used to deposit excess iodine-eliminated cuprous iodide on to the working electrode. Optimum efficiency of 2.11% was obtained for the dye-sensitized solid-state solar cell fabricated using D-149 dye and 1.6% was obtained for N-719 dye. The highest solar parameters obtained were shown for the dye-sensitized solid-state solar cell fabricated for D-149 dye which were an open circuit photo-voltage of 475 mV and short circuit current density of 12.7 A cm⁻².