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In situ Raman study of the photoinduced behavior of dye molecules on TiO₂(hkl) single crystal surfaces.

ABSTRACT: In dye-sensitized solar cells (DSSCs), the TiO₂/dye interface significantly affects photovoltaic performance. However, the adsorption and photoinduced behavior of dye molecules on the TiO₂ substrate remains unclear. Herein, shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) was used to study the adsorption and photoinduced behavior of dye (N719) molecules on different TiO₂(hkl) surfaces. On TiO₂(001) and TiO₂(110) surfaces, the in situ SHINERS and mass spectrometry results indicate S[double bond, length as m-dash]C bond cleavage in the anchoring groups of adsorbed N719, whereas negligible bond cleavage occurs on the TiO₂(111) surface. Furthermore, DFT calculations show the stability of the S[double bond, length as m-dash]C anchoring group on three TiO₂(hkl) surfaces in the order TiO₂(001) < TiO₂(110) < TiO₂(111), which correlated well with the observed photocatalytic activities. This work reveals the photoactivity of different TiO₂(hkl) surface structures and can help with the rational design of DSSCs. Thus, this strategy can be applied to real-time probing of photoinduced processes on semiconductor single crystal surfaces.

SUBMITTER: Zhang SP

PROVIDER: S-EPMC8159273 | biostudies-literature |

REPOSITORIES: biostudies-literature

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