title: Initial light soaking treatment enables hole transport material to outperform spiro-OMeTAD in solid-state dye-sensitized solar cells.
abstract: Efficient solid state dye-sensitized solar cells (sDSCs) were obtained using a small hole transport material, MeO-TPD (N,N,N',N'-tetrakis(4-methoxyphenyl)benzidine), after an initial light soaking treatment. It was discovered that the light soaking treatment for the MeO-TPD based solar cells is essential in order to achieve the high efficiency (4.9%), which outperforms spiro-OMeTAD based sDSCs using the same dye and device preparation parameters. A mechanism based on Li(+) ion migration is suggested to explain the light soaking effect. It was observed that the electron lifetime for the MeO-TPD based sDSC strongly increases after the light soaking treatment, which explains the higher efficiency. After the initial light soaking treatment the device efficiency remains considerably stable with only 0.2% decrease after around 1 month (unsealed cells stored in dark).
authors.affiliation: Department of Chemistry-Ångström Laboratory, Uppsala University, Sweden.
authors.forename: Lei
authors.initials: L
authors.lastname: Yang
authors.forename: Bo
authors.initials: B
authors.lastname: Xu
authors.forename: Dongqin
authors.initials: D
authors.lastname: Bi
authors.forename: Haining
authors.initials: H
authors.lastname: Tian
authors.forename: Gerrit
authors.initials: G
authors.lastname: Boschloo
authors.forename: Licheng
authors.initials: L
authors.lastname: Sun
authors.forename: Anders
authors.initials: A
authors.lastname: Hagfeldt
authors.forename: Erik M J
authors.initials: EM
authors.lastname: Johansson