title: Overcoming ultraviolet light instability of sensitized TiO₂ with meso-superstructured organometal tri-halide perovskite solar cells.
abstract: The power conversion efficiency of hybrid solid-state solar cells has more than doubled from 7 to 15% over the past year. This is largely as a result of the incorporation of organometallic trihalide perovskite absorbers into these devices. But, as promising as this development is, long-term operational stability is just as important as initial conversion efficiency when it comes to the development of practical solid-state solar cells. Here we identify a critical instability in mesoporous TiO₂-sensitized solar cells arising from light-induced desorption of surface-adsorbed oxygen. We show that this instability does not arise in mesoporous TiO₂-free mesosuperstructured solar cells. Moreover, our TiO₂-free cells deliver stable photocurrent for over 1,000 h continuous exposure and operation under full spectrum simulated sunlight.
authors.affiliation: University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX13PU, UK.
authors.forename: Tomas
authors.initials: T
authors.lastname: Leijtens
authors.forename: Giles E
authors.initials: GE
authors.lastname: Eperon
authors.forename: Sandeep
authors.initials: S
authors.lastname: Pathak
authors.forename: Antonio
authors.initials: A
authors.lastname: Abate
authors.forename: Michael M
authors.initials: MM
authors.lastname: Lee
authors.forename: Henry J
authors.initials: HJ
authors.lastname: Snaith