Preparation and enhanced properties of dye-sensitized solar cells by surface plasmon resonance of Ag nanoparticles in nanocomposite photoanode

A series of TiO2 photoanodes with differing amounts of Ag nanoparticles (NPs) on TiO2 in core-shell form (Ag@TiO2) are prepared and used to make a series of dye-sensitized solar cells (DSSCs). The influence of different amounts of Ag–NPs on the structure and performance of the DSSCs is investigated. Studies indicate that the short-circuit current density (Jsc), open-circuit voltage (Voc), charge lifetime and dark current of DSSCs containing Ag–NPs are significantly improved. The best performance is achieved in the DSSCs with 0.15 wt% Ag–NPs additions, with the maximum Jsc of 10.19 mA cm−2, highest Voc of 698 mV and best photoelectric conversion efficiency of 5.33%, significantly superior to that of the DSSCs with pure TiO2 photoanodes. The increase of Jsc is attributed to the enhanced dye light absorption in strength and spectral range due to the surface plasmon resonance of Ag–NPs in photoanode, while the increase of Voc may be related to the more negative level of the quasi-Fermi energy of Ag–TiO2 composite system resulting from the added Ag.

► Different amounts of Ag@TiO2 core-shell nanoparticles were incorporated into DSSCs.
► The properties of the DSSC with 0.15 wt% Ag were significantly improved.
► The increase of Jsc may be attributed to enhanced dye light absorption.
► The enhanced light absorption was attributed to surface plasmon resonance of Ag.
► The increase of Voc was attributed to the change of Fermi energy of Ag-TiO2 system.