Title: Correlating Crystallographic Orientation and Ferroic Properties of Twin Domains in Metal Halide Perovskites

Abstract

Metal halide perovskite (MHP) solar cells have attracted worldwide research interest. Although it has been well established that grain, grain boundary, and grain facet affect MHPs optoelectronic properties, less is known about subgrain structures. Recently, MHP twin stripes, a subgrain feature, have stimulated extensive discussion due to the potential for both beneficial and detrimental effects of ferroelectricity on optoelectronic properties. Furthermore, connecting the ferroic behavior of twin stripes in MHPs with crystal orientation will be a vital step to understand the ferroic nature and the effects of twin stripes. In this work, we studied the crystallographic orientation and ferroic properties of CH₃NH₃PbI₃ twin stripes, using electron backscatter diffraction (EBSD) and advanced piezoresponse force microscopy (PFM), respectively. Using EBSD, we discovered that the orientation relationship across the twin walls in CH₃NH₃PbI₃ is a 90° rotation about ($$\bar{11}0$$), with the (030) and (111) directions parallel to the direction normal to the surface. By careful inspection of CH₃NH₃PbI₃ PFM results including in-plane and out-of-plane PFM measurements, we demonstrate some nonferroelectric contributions to the PFM responses of this CH₃NH₃PbI₃ sample, suggesting that the PFM signal in this CH₃NH₃PbI₃ sample is affected by nonferroelectric and nonpiezoelectric forces. If there is piezoelectric response, it is below the detection sensitivity of our interferometric displacement sensor PFM (<0.615 pm/V). Overall, this work offers an integrated picture describing the crystallographic orientations and the origin of PFM signal of MHPs twin stripes, which is critical to understanding the ferroicity in MHPs.

Authors:

Liu, Yongtao  ^[1];

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• Search DOE PAGES for ORCID "0000-0003-0152-1783"

Trimby, Patrick ^[2]; Collins, Liam  ^[3];

• Search DOE PAGES for author "Collins, Liam"
• Search DOE PAGES for ORCID "0000-0003-4946-9195"

Ahmadi, Mahshid  ^[4];

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• Search DOE PAGES for ORCID "0000-0002-3268-7957"

Winkelmann, Aimo ^[5]; Proksch, Roger  ^[6];

• Search DOE PAGES for author "Proksch, Roger"
• Search DOE PAGES for ORCID "0000-0003-2124-1201"

Ovchinnikova, Olga S.  ^[7]

• Search DOE PAGES for author "Ovchinnikova, Olga S."
• Search DOE PAGES for ORCID "0000-0001-8935-2309"

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+ Show Author Affiliations

1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS); Univ. of Tennessee, Knoxville, TN (United States)
2. Oxford Instruments Nanoanalysis, High Wycombe (United Kingdom)
3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)
4. Univ. of Tennessee, Knoxville, TN (United States)
5. AGH Univ. of Science and Technology, Krakow (Poland). Academic Centre for Materials and Nanotechnology (ACMiN)
6. Asylum Research, An Oxford Instruments Co., Santa Barbara, CA (United States)
7. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Publication Date:

Fri Mar 26 00:00:00 EDT 2021

Research Org.:

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:

USDOE Office of Science (SC); Polish National Agency for Academic Exchange (NAWA)

OSTI Identifier:

1819579

Grant/Contract Number:  

AC05-00OR22725; PPN/ULM/2019/1/00068/U/00001

Resource Type:

Accepted Manuscript

Journal Name:

ACS Nano

Additional Journal Information:

Journal Volume: 15; Journal Issue: 4; Journal ID: ISSN 1936-0851

Publisher:

American Chemical Society (ACS)

Country of Publication:

United States

Language:

English

Subject:

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; metal halide perovskites; piezoresponse force microscopy; ferroelectricity; piezoelectricity; electron backscatter diffraction; crystallography; optoelectronics; resonance structures; polarization