title: The influence of shell thickness of Au@TiO2 core-shell nanoparticles on the plasmonic enhancement effect in dye-sensitized solar cells.
abstract: Plasmonic core-shell nanoparticles (PCSNPs) can function as nanoantennas and improve the efficiency of dye-sensitized solar cells (DSSCs). To achieve maximum enhancement, the morphology of PCSNPs needs to be optimized. Here we precisely control the morphology of Au@TiO2 PCSNPs and systematically study its influence on the plasmonic enhancement effect. The enhancement mechanism was found to vary with the thickness of the TiO2 shell. PCSNPs with a thinner shell mainly enhance the current, whereas particles with a thicker shell improve the voltage. While pronounced plasmonic enhancement was found in the near infrared regime, wavelength-independent enhancement in the visible range was observed and attributed to the plasmonic heating effect. Emission lifetime measurement confirms that N719 molecules neighboring nanoparticles with TiO2 shells exhibit a longer lifetime than those in contact with metal cores. Overall, PCSNPs with a 5 nm shell give the highest efficiency enhancement of 23%. Our work provides a new synthesis route for well-controlled Au@TiO2 core-shell nanoparticles and gains insight into the plasmonic enhancement in DSSCs.
authors.affiliation: Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan.
authors.forename: Wei-Liang
authors.initials: WL
authors.lastname: Liu
authors.forename: Fan-Cheng
authors.initials: FC
authors.lastname: Lin
authors.forename: Yu-Chen
authors.initials: YC
authors.lastname: Yang
authors.forename: Chen-Hsien
authors.initials: CH
authors.lastname: Huang
authors.forename: Shangjr
authors.initials: S
authors.lastname: Gwo
authors.forename: Michael H
authors.initials: MH
authors.lastname: Huang
authors.forename: Jer-Shing
authors.initials: JS
authors.lastname: Huang
mesh_terms: D004396:Coloring Agents / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D012666:Semiconductors; D012993:Solar Energy; D014025:Titanium / Q000737:chemistry*
chemical_list: D004396:Coloring Agents; C009495:titanium dioxide; D006046:Gold; D014025:Titanium