Unraveling the Impact of Halide Mixing on Perovskite Stability
Hieulle, Jeremy (Okinawa Institute of Science and Technology Graduate University)
Wang, Xiaoming (University of Toledo. Department of Physics and Astronomy and Wright)
Stecker, Collin (Okinawa Institute of Science and Technology Graduate University)
Son, Dae-Yong (Okinawa Institute of Science and Technology Graduate University)
Qiu, Longbin (Okinawa Institute of Science and Technology Graduate University)
Ohmann, Robin (Okinawa Institute of Science and Technology Graduate University)
Ono, Luis K. (Okinawa Institute of Science and Technology Graduate University)
Mugarza, Aitor (Institut Català de Nanociència i Nanotecnologia)
Yan, Yanfa (University of Toledo. Department of Physics and Astronomy and Wright)
Qi, Yabing (Okinawa Institute of Science and Technology Graduate University)

Date:	2019
Abstract:	Increasing the stability of perovskites is essential for their integration in commercial photovoltaic devices. Halide mixing is suggested as a powerful strategy toward stable perovskite materials. However, the stabilizing effect of the halides critically depends on their distribution in the mixed compound, a topic that is currently under intense debate. Here we successfully determine the exact location of the I and Cl anions in the CH NH PbBr I and CH NH PbBr Cl mixed halide perovskite lattices and correlate it with the enhanced stability we find for the latter. By combining scanning tunneling microscopy and density functional theory, we predict that, for low ratios, iodine and chlorine incorporation have different effects on the electronic properties and stability of the CH NH PbBr perovskite material. In addition, we determine the optimal Cl incorporation ratio for stability increase without detrimental band gap modification, providing an important direction for the fabrication of stable perovskite devices. The increased material stability induced by chlorine incorporation is verified by performing photoelectron spectroscopy on a half-cell device architecture. Our findings provide an answer to the current debate on halide incorporation and demonstrate their direct influence on device stability.
Grants:	Ministerio de Economía y Competitividad SEV-2017-0706
Rights:	Aquest material està protegit per drets d'autor i/o drets afins. Podeu utilitzar aquest material en funció del que permet la legislació de drets d'autor i drets afins d'aplicació al vostre cas. Per a d'altres usos heu d'obtenir permís del(s) titular(s) de drets.
Language:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Subject:	Band-gap modification ; Device architectures ; Enhanced stability ; Halide perovskites ; Incorporation ratio ; Material stability ; Photovoltaic devices ; Stabilizing effects
Published in:	Journal of the American Chemical Society, Vol. 141, Issue 8 (February 2019) , p. 3515-3523, ISSN 1520-5126

DOI: 10.1021/jacs.8b11210
PMID: 30646682

Postprint 9 p, 3.3 MB

The record appears in these collections:
Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Articles > Research articles
Articles > Published articles