Chandiran, Aravind KumarYella, AswaniMayer, Matthew T.Gao, PengNazeeruddin, Mohammad KhajaGraetzel, Michael2014-08-292014-08-292014-08-29201410.1002/adma.201306271https://infoscience.epfl.ch/handle/20.500.14299/106328WOS:000339007000014A mere 2 nm conformal titanium dioxide overlayer coated by atomic layer deposition is shown to act as a blocking layer for high-efficiency solid-state perovskite (CH3NH3PbI3) absorber-based solar cells. Surpassing the existing multilayer passivation, this ultrathin sub-nanometer layer leads to a photovoltaic power conversion efficiency of 11.5%.text::journal::journal article::research article