Title: Synergistic Role of Water and Oxygen Leads to Degradation in Formamidinium-Based Halide Perovskites

Abstract

Mixed-cation metal halide perovskites have shown remarkable progress in photovoltaic applications with high power conversion efficiencies. However, to achieve large-scale deployment of this technology, efficiencies must be complemented by long-term durability. The latter is limited by external factors, such as exposure to humidity and air, which lead to the rapid degradation of the perovskite materials and devices. In this work, we study the mechanisms causing Cs and formamidinium (FA)- based halide perovskite phase transformations and stabilization during moisture and air exposure. We use in situ X-ray scattering, X-ray photoelectron spectroscopy, and first-principles calculations to study these chemical interactions and their effects on structure. We unravel a surface reaction pathway involving the dissolution of FAI by water and iodide oxidation by oxygen, driving the Cs/FA ratio into thermodynamically unstable regions, leading to undesirable phase transformations. This work demonstrates the interplay of bulk phase transformations with surface chemical reactions, providing a detailed understanding of the degradation mechanism and strategies for designing durable and efficient perovskite materials.

Authors:

Hidalgo, Juanita  ^[1];

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• Search DOE PAGES for ORCID "0000-0002-5832-3262"

Kaiser, Waldemar  ^[2];

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• Search DOE PAGES for ORCID "0000-0001-9069-690X"

An, Yu  ^[1];

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• Search DOE PAGES for ORCID "0000-0002-1382-5293"

Li, Ruipeng ^[3]; Oh, Zion ^[1]; Castro-Méndez, Andrés-Felipe ^[1]; LaFollette, Diana K. ^[1]; Kim, Sanggyun ^[1]; Lai, Barry ^[4]; Breternitz, Joachim  ^[5];

• Search DOE PAGES for author "Breternitz, Joachim"
• Search DOE PAGES for ORCID "0000-0002-0192-6919"

Schorr, Susan ^[6]; Perini, Carlo A. R. ^[1]; Mosconi, Edoardo  ^[2];

• Search DOE PAGES for author "Mosconi, Edoardo"
• Search DOE PAGES for ORCID "0000-0001-5075-6664"

De Angelis, Filippo  ^[7];

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• Search DOE PAGES for ORCID "0000-0003-3833-1975"

Correa-Baena, Juan-Pablo  ^[1]

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• Search DOE PAGES for ORCID "0000-0002-3860-1149"

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+ Show Author Affiliations

1. School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
2. Computational Laboratory for Hybrid/Organic Photovoltaics (CLHYO), Istituto CNR di Scienze e Tecnologie Chimiche “Giulio Natta” (CNR-SCITEC), Perugia 06123, Italy
3. National Synchrotron Light Source II, Brookhaven National Lab, Upton, New York 11973, United States
4. Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois 60439, United States
5. Department of Structure and Dynamics of Energy Materials, Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, Berlin 14109, Germany
6. Department of Structure and Dynamics of Energy Materials, Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, Berlin 14109, Germany, Freie Universitaet Berlin, Institute of Geological Sciences, Malteser Str. 74-200, Berlin 12249, Germany
7. Computational Laboratory for Hybrid/Organic Photovoltaics (CLHYO), Istituto CNR di Scienze e Tecnologie Chimiche “Giulio Natta” (CNR-SCITEC), Perugia 06123, Italy, Department of Chemistry, Biology and Biotechnology, University of Perugia and UdR INSTM, Perugia 06123, Italy, Department of Natural Sciences & Mathematics, College of Sciences & Human Studies, Prince Mohammad Bin Fahd University, Dhahran 34754, Saudi Arabia, SKKU Institute of Energy Science and Technology (SIEST), Sungkyunkwan University, Suwon 440-746, Korea

Publication Date:

Thu Nov 02 00:00:00 EDT 2023

Research Org.:

Georgia Institute of Technology, Atlanta, GA (United States); Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF)

OSTI Identifier:

2204524

Alternate Identifier(s):

OSTI ID: 2212445; OSTI ID: 2242388

Report Number(s):

BNL-225062-2023-JAAM
Journal ID: ISSN 0002-7863; jacs.3c05657

Grant/Contract Number:  

SC0012704; DGE-2039655; ECCS-1542174

Resource Type:

Published Article

Journal Name:

Journal of the American Chemical Society

Additional Journal Information:

Journal Name: Journal of the American Chemical Society; Journal ID: ISSN 0002-7863

Publisher:

American Chemical Society

Country of Publication:

United States

Language:

English

Subject:

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE; anions; oxygen; perovskites; phase transitions; solar cells