Effect of Natural Sensitizers Anchoring to Nanoporous TiO2 on Performance of Dye-Sensitized Solar Cells

摘要

Dyes extracted from leaves and flowers of plants were used as sensitizers in dye-sensitized solar cells (DSSCs). The TiO2 photoanodes were deposited on cleaned fluorine-doped tin oxide transparent conducting glass substrates by a doctor blade coating technique. The obtained photoanodes were immersed in the prepared dyes and analyzed through their absorption and fluorescence spectra. The structural and morphological properties of developed photoanodes were studied. The natural pigments lawsone and scopoletin exhibit unique qualities due to their solar light absorption and excellent chemical structure, which enable them to effectively and firmly bind with the TiO2 surface due to their carboxyl groups. The assembled DSSCs were tested and analyzed to determine their photoelectrical performance. The solar-to-current energy conversion efficiency of a DSSC using mallow as a sensitizer was higher than those using other natural dyes, with a short-circuit current density of 0.69 mA/cm(2) and more stable performance under illumination. The laser beam-induced current measurements showed unfilled zones with electrolytic solution and induced degradation of the DSSC performance.