Dye-sensitized solar cells based on Au/SnS/TiO2 sensitized by natural dye

A photoanode composed of Au/SnS/TiO2 sensitized by natural dye is designed and fabricated for dye-sensitized solar cells (DSSCs). A layer of spherical nano-TiO2 is prepared by calcination and a layer of nano-SnS is deposited on the TiO2 photoanode by the continuous ion layer adsorption reaction (SILAR). The Au nanoparticles are modified and sensitized with natural dye. The Au nanoparticles exhibit excellent localized surface plasmon resonance (LSPR) effects and enhanced the electron trapping ability. Owing to the smaller bandgap of SnS and optical activity in the infrared region, the electron mobility improves and electron recombination decreases. Electrochemical assessment reveals that the photoelectric characteristics of the DSSC based on Au/SnS/TiO2 are greatly improved after natural dye sensitization and compared with the TiO2 photoanode, the power conversion efficiency (PCE) of the DSSC improves by 105%.