ZnO:Ag and TZO:Ag Plasmonic Nanocomposite for Enhanced Dye Sensitized Solar Cell Performance

Bilayer TiO2:Ag/ZnO:Ag (TZO:Ag) oxide film is fabricated by using silver doped zinc oxide (ZnO:Ag) and silver doped titanium dioxide (TiO2:Ag) nanopowder synthesized by sol–gel Technique. X-ray diffraction (XRD) and UV-Visible spectroscopy (UV-Vis) results confirm the formation of TZO:Ag film. Band gap energies are 2.96eV, 2.99eV and 3.02eV for annealed TiO2:Ag, ZnO:Ag and TZO:Ag respectively. Short-circuit photocurrent density (Jsc) is increased from 0.106mA/cm2 for the DSSCs with a single ZnO film to 0.495mA/cm2 and 0.461mA/cm2 for the DSSCs with a ZnO:Ag thin film and TZO:Ag thin film, respectively. Efficiency (η) of DSSC has been improved to 345.71% and 351.428% with Ag doped ZnO and ZTO film respectively as compared to undoped ZnO film. This improvement is attributed to the presence of localized surface plasmon resonance (SPR) effect associated with spatially dispersed metallic Ag nanoparticles on the surface of oxide nanoparticles, which enhances the light-harvesting efficiency and promotes the separation of photogenerated electron-hole pairs.