Significant improvement in the conversion efficiency of black-dye-based dye-sensitized solar cells by cosensitization with organic dye

The conversion efficiency of black-dye-based dye-sensitized solar cell (DSC) was improved by cosensitization with organic dye (NKX-2553 or D131). This improved conversion efficiency was further enhanced by employing deoxycholic acid (DCA) as a coadsobent. The highest conversion efficiency, 11.6% under AM 1.5 irradiation (100 mW cm−2), was obtained in DSC with black dye and D131 in the presence of DCA.