Enhancement of dye-sensitized solar cells performances by improving electron density in conduction band of nanostructure TiO2 electrode with using a metalloporphyrin as additional dye

► N719 and ZnTCPP dyes were used in a sequential adsorption process. ► By using two dyes, improved the performance of the cell. ► Density of electrons in the conduction band of TiO2 electrodes improved.