Artículos de revistas
Surface passivation of nanoporous TiO2 via atomic layer deposition of ZrO2 for solid-state dye-sensitized solar cell applications
Fecha
2009-11-20Registro en:
Journal of Physical Chemistry C, v. 113, n. 42, p. 18385-18390, 2009.
1932-7447
1932-7455
10.1021/jp906573w
2-s2.0-70449561262
Autor
Northwestern University
Universität Jaume I
Universidade Estadual Paulista (UNESP)
Institución
Resumen
We report here the utilization of atomic layer deposition to passivate surface trap states in mesoporous TiO2 nanoparticles for solid-state dye-sensitized solar cells based on 2,2',7,7'-tetrak.is(N, N-di-p- methoxyphenylamine)9,9'-spirobifluorene (spiro-OMeTAD). By depositing ZrO 2 films with angstrom-level precision, coating the inesoporous TiO2 produces over a two-fold enhancement in short-circuit current density, as compared to a control device. Impedance spectroscopy measurements provide evidence that the ZrO2 coating reduces recombination losses at the TiO2/spiro-OMeTAD interface and passivates localized surface states. Lowfrequency negative capacitances, frequently observed in nanocomposite solar cells, have been associated with the surface-state mediated charge transfer from TiO2 to the spiro-OMeTAD. © 2009 American Chemical Society.