Bioinspired synthesis of Ag@TiO₂ plasmonic nanocomposites to enhance the light harvesting of dye-sensitized solar cells

Dye-sensitized solar cells (DSSCs) are attracting increasing attention as a promising technology for renewable energy production, and the localized surface plasmons (LSPs) of metal nanoparticles (NPs) is being actively explored to enhance the performance of DSSCs. Herein, plasmid DNA was employed as a bioscaffold to fabricate Ag@TiO₂ plasmonic nanocomposites for DSSCs. The effect of the nanocomposites on the light harvesting and the dependence of the amount of the nanocomposites in the photoanode on the performance of plasmonic DSSCs were investigated. It was found that plasmid DNA not only worked as a scaffold to drive the formation of the nanocomposites, but also acted as an effective reducing agent under the UV irradiation. Due to the nanocomposites working as "plasmonic components" in the photoanode, compared with conventional TiO₂-only DSSCs, the light harvesting, corresponding photocurrent, and power conversion efficiency (PCE) were enhanced in the presence of the nanocomposites. Specially, when the amount of Ag NPs in the plasmonic photoanode was 0.8 wt%, the PCE was 1.83%, increased by ∼28.87% compared with 1.42% for the TiO₂-only DSSC. Additionally, plasmonic DSSCs reduced the materials required by ∼30% for DSSC fabrication to maintain the same performance as conventional TiO₂-only DSSCs.