%0 Journal Article %A Luo, Yanqi %A Gamliel, Shany %A Nijem, Sally %A Aharon, Sigalit %A Holt, Martin %A Stripe, Benjamin %A Rose, Volker %A Bertoni, Mariana I. %A Etgar, Lioz %A Fenning, David P. %D 2016 %T Spatially Heterogeneous Chlorine Incorporation in Organic–Inorganic Perovskite Solar Cells %U https://acs.figshare.com/articles/journal_contribution/Spatially_Heterogeneous_Chlorine_Incorporation_in_Organic_Inorganic_Perovskite_Solar_Cells/3826359 %R 10.1021/acs.chemmater.6b02065.s001 %2 https://acs.figshare.com/ndownloader/files/5964753 %K halide perovskite absorbers %K synchrotron-based nanoprobe X-ray fluorescence %K Spatially Heterogeneous Chlorine Incorporation %K Cl-containing precursors %K chlorine %K CH 3 NH 3 PbI 3 films %K film photovoltaic devices %X Spatial heterogeneities in the chemical makeup of thin film photovoltaic devices are pivotal in determining device efficiency. We report the in-plane spatial distribution and degree of chlorine incorporation in organic–inorganic lead halide perovskite absorbers by means of nondestructive synchrotron-based nanoprobe X-ray fluorescence. The presence of chlorine is positively identified in CH3NH3PbI3 films synthesized with Cl-containing precursors and as an impurity in some films synthesized with nominally Cl-free precursors. The impurity may be introduced from precursors or as contaminants during film synthesis. The films formed from Cl-containing precursors contain roughly an order of magnitude higher amount of chlorine, with Cl:I values greater than 0.02 found whether Cl is present in either the organic or the inorganic precursor for both one- and two-step fabrication processes. A spatial variation in the Cl incorporation is observed within single particles and as well as between particles within a given film, and the standard deviation of the Cl:I ratio across the films is up to 30% of the average value. Understanding and controlling the heterogeneous distribution of chlorine in hybrid perovskite layers may offer a path to improve their photovoltaic performance. %I ACS Publications