@article{845c71ba3f264cf88c67a39ae26e5eba,
title = " The existence and impact of persistent ferroelectric domains in MAPbI 3 ",
abstract = " Methylammonium lead iodide (MAPbI 3 ) exhibits exceptional photovoltaic performance, but there remains substantial controversy over the existence and impact of ferroelectricity on the photovoltaic response. We confirm ferroelectricity in MAPbI 3 single crystals and demonstrate mediation of the electronic response by ferroelectric domain engineering. The ferroelectric response sharply declines above 57°C, consistent with the tetragonal-to-cubic phase transition. Concurrent band excitation piezoresponse force microscopy–contact Kelvin probe force microscopy shows that the measured response is not dominated by spurious electrostatic interactions. Large signal poling (>16 V/cm) orients the permanent polarization into large domains, which show stabilization over weeks. X-ray photoemission spectroscopy results indicate a shift of 400 meV in the binding energy of the iodine core level peaks upon poling, which is reflected in the carrier concentration results from scanning microwave impedance microscopy. The ability to control the ferroelectric response provides routes to increase device stability and photovoltaic performance through domain engineering. ",
author = "Garten, {Lauren M.} and Moore, {David T.} and Nanayakkara, {Sanjini U.} and Shyam Dwaraknath and Philip Schulz and Jake Wands and Angus Rockett and Brian Newell and Persson, {Kristin A.} and Susan Trolier-McKinstry and Ginley, {David S.}",
note = "Funding Information: This work was funded by the Center for the Next Generation of Materials by Design, a U.S. Department of Energy, Office of Science EFRC, under contract no. DE-AC36-08GO28308 to NREL. D.T.M. acknowledges support from the NREL Director{\textquoteright}s Fellowship LDRD program. We acknowledge S. Neumayer and S. Jesse (ORNL) for facilitating the Be-PFM/cKPFM measurements conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. S.T.M. gratefully acknowledges the NSF (DMR-1420620). A.R. and J.W. acknowledge support under the Department of Energy grant DE-EE0007545. P.S. thanks the French Agence Nationale de la Recherche for funding under contract number ANR-17-MPGA-0012 and was supported by the hybrid perovskite solar cell program of the National Center for Photovoltaics funded by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Office of Solar Energy Technology under award number DE-AC36-08GO28308DOE with NREL. Publisher Copyright: Copyright {\textcopyright} 2019 The Authors.",
year = "2019",
month = jan,
day = "25",
doi = "10.1126/sciadv.aas9311",
language = "English (US)",
volume = "5",
journal = "Science advances",
issn = "2375-2548",
publisher = "American Association for the Advancement of Science",
number = "1",
}