Plasmonic Effects of Infiltrated Silver Nanoparticles Inside TiO2 Film: Enhanced Photovoltaic Performance in DSSCs

The plasmonic effects of infiltrated silver (Ag) nanoparticles, with different contents, inside a nanostructured TiO 2 film on the photovoltaic performance of dye‐sensitized solar cells ( DSSC s) are explored. The synthesized Ag nanoparticles are immobilized onto deposited TiO 2 nanoparticles by a new strategy using 3‐mercaptopropionic acid ( MPA ), a bifunctional linker molecule. Transmission electron microscope ( TEM ) images show that monodispersed Ag and polydispersed TiO 2 nanoparticles have an average diameter of 12 ± 3 nm and 5 ± 1 nm, respectively. Moreover, Fourier transform infrared spectroscopy ( FTIR ) analysis reveals that Ag nanoparticles were successfully functionalized and capped with MPA. Optical studies on the MPA ‐capped Ag nanoparticles inside TiO 2 film show an increase in the total absorbance of the electrode. Moreover, EIS measurements confirm that MPA ‐capped Ag nanoparticles inhibit the charge recombination and improve the stability of nanoparticles in I 3 − / I − electrolyte. The DSSC assembled with optimal content of MPA ‐capped Ag nanoparticles demonstrated an enhanced power conversion efficiency (8.82% ± 0.07%) compared with the pure TiO 2 (7.30% ± 0.05%). The increase in cell efficiency was attributed to the enhanced dye light absorption in strength and spectral range due to the surface plasmon resonance of MPA ‐capped Ag nanoparticles in the photoanode.