Photocurrent Enhancement of Dye-Sensitized Solar Cells owing to Increased Dye-Adsorption onto Silicon-Nanoparticle-Coated Titanium-Dioxide Films

The inverse‐micellar preparation of Si nanoparticles (Nps) was improved by utilizing sodium naphthalide. The Si Nps were subsequently functionalized with 4‐vinylbenzoic acid for their attachment onto TiO2 films of dye‐sensitized solar cells (DSSCs). The average diameter of the COOH‐functionalized Si (SiCOOH) Nps was 4.6(±1.7) nm. Depth profiling by secondary‐ion mass spectrometry revealed that the Si Nps were uniformly attached onto the TiO2 films. The number of RuII dye molecules adsorbed onto a TiO2 film that was treated with the SiCOOH Nps was 42 % higher than that on the untreated TiO2 film. As a result, DSSCs that incorporated the SiCOOH Nps exhibited higher short‐circuit photocurrent density and an overall energy‐conversion efficiency than the untreated DSSCs by 22 % and 27 %, respectively. This enhanced performance, mostly owing to the intramolecular charge‐transfer to TiO2 from the dye molecules that were anchored to the SiCOOH Nps, was confirmed by comparing the performance with two different RuII–bipyridine dyes (N719 and N749). Dye another day: The preparation of Si nanoparticles (Nps) was improved by using sodium naphthalide. The Si Nps were functionalized with 4‐vinylbenzoic acid and attached onto TiO2 films for application in dye‐sensitized solar cells (DSSCs). The DSSCs that contained SiCOOH Nps exhibited 22 % and 27 % higher short‐circuit photocurrent density and overall energy‐conversion efficiency than the untreated DSSCs, respectively.