Fabrication of dye-sensitized solar cells using natural dye for food pigment: Monascus yellow

A food pigment (Monascus yellow) extracted from Monascus fermentations (red yeast rice) has been studied as a novel sensitizing dye for dye-sensitized solar cells (DSCs). The photocurrent action spectrum was in agreement with the absorption spectrum of the dye adsorbed on a nanocrystalline-TiO2 electrode. The DSC fabrication process has been optimized in terms of the rinsing solvent used after dye adsorption and the dye-uptake duration. After optimizing nanocrystalline-TiO2 electrodes and pH conditions, the resulting maximal photovoltaic characteristics were an open-circuit voltage of 0.57 V, a short-circuit current of 6.1 mA cm−2, and a fill factor of 0.66, yielding an energy conversion efficiency of 2.3%.