Au plasmonic effect on the Voc, Jsc and efficiency of the Au-embedded TiO2-based DSSC solar cell

Abstract

In this study the influence of the plasmonic effect of gold nanoparticles on the parameters (Voc, Jsc and efficiency) of Au-embedded TiO2-based DSSC solar cells was investigated. The gold nanoparticles were successfully embedded into the TiO2 films by means of vacuum evaporation combined with thermal annealing. A thin Au layer was deposited first on TiO2 film by the thermal evaporation then annealed at a temperature of 400 oC to get nanocomposite films. It was found that the Au nanoparticles were well dispersed on the TiO2 films and their average size changed from 14 nm to 35 nm when the deposited gold layer changed from 3 nm to 8 nm. The surface plasmon resonance (SPR) absorption spectrum of Au@TiO2 films was observed in the wavelength range from 534 nm to 614 nm, depending on the gold nanoparticles size. The Au@TiO2 thin films were used as photo-anode for manufacturing the DSSC solar cells in configuration of FTO/Au@TiO2/(I-/I2-) electrolyte/Pt. The I-V characteristics of the cells were measured under irradiation of the visible light. The results indicate that, the short-circuit current (Jsc) and open-circuit voltage (Voc) of the Au@TiO2 films based solar cell and its efficiency were much improved, due to a contribution of the surface plasmon resonance (SPR) effect