Nanoscale heterogeneity in CsPbBr3 and CsPbBr3:KI perovskite films revealed by cathodoluminescence hyperspectral imaging

Lethy Krishnan Jagadamma; P Edwards; R Martin; Arvydas Ruseckas; Ifor David William Samuel

doi:10.1021/acsaem.0c03154

Nanoscale heterogeneity in CsPbBr₃ and CsPbBr₃:KI perovskite films revealed by cathodoluminescence hyperspectral imaging

Lethy Krishnan Jagadamma, P Edwards, R Martin, Arvydas Ruseckas, Ifor David William Samuel

Research output: Contribution to journal › Article › peer-review

Abstract

The nanoscale morphology of solar cell materials strongly affects their performance. We report direct evidence for the existence of multiple length scales of heterogeneity in halide perovskites such as CsPbBr₃ and CsPbBr₃:KI. Contrary to the general notion of two distinct phases, our study suggests the presence of multiple phases in mixed halide perovskites. Highly spatially resolved (≈50 nm) cathodoluminescence maps reveal that the length scale of heterogeneity is composition dependent: smaller (≈ 200 nm) for CsPbBr₃, and larger (≈500–1000 nm) for CsPbBr₃:KI. Moreover, these nano-/micro-scale heterogeneities exist both laterally and vertically in mixed halides and correlate with high densities of carrier traps and fast trap-assisted recombination. The observed heterogeneities also lead to reduced power conversion efficiency of solar cells, higher hysteresis loss, and faster degradation. These insights argue for advanced nanoscale characterization of halide perovskites to guide reduction of heterogeneity and so improve device performance and stability.

Original language	English
Pages (from-to)	2707–2715
Journal	ACS Applied Energy Materials
Volume	4
Issue number	3
Early online date	8 Mar 2021
DOIs	https://doi.org/10.1021/acsaem.0c03154
Publication status	Published - 22 May 2021

Keywords

Halide perovskites
Grain-to-grain inhomogeneity
Gradient in bandgap
Local strain
Local phase segregation

Access to Document

10.1021/acsaem.0c03154

Manuscript_ACS_AEM
Copyright © 2021 American Chemical Society. This work has been made available online in accordance with publisher policies or with permission. Permission for further reuse of this content should be sought from the publisher or the rights holder. This is the author created accepted manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.1021/acsaem.0c03154.
Accepted author manuscript, 1.21 MB

H2020 MSCA - PHOTOPEROVSKITIES: H2020 MSCA Fellowship 2016 Lethy
Samuel, I. D. W. (PI)
European Commission
1/09/17 → 31/08/19
Project: Fellowship
Equipment Account: Characterisation and Manipulation of Advanced Functional Materials and their Interfaces at the Nanoscale
Samuel, I. D. W. (PI)
EPSRC
1/10/13 → 30/09/23
Project: Standard

Nanoscale heterogeneity in CsPbBr3 and CsPbBr3:KI perovskite films revealed by cat hodoluminescence hyperspectral imaging (dataset)
Krishnan Jagadamma, L. (Creator), edwards, P. (Creator), martin, R. (Creator) & Samuel, I. D. W. (Creator), University of St Andrews, 9 Mar 2021
DOI: 10.17630/4b1c9e3d-7787-40c8-aade-1dcf1af62315
Dataset

File

Cite this

@article{15004c0ff6d04426b3e7bd6cf2a25e5d,

title = "Nanoscale heterogeneity in CsPbBr3 and CsPbBr3:KI perovskite films revealed by cathodoluminescence hyperspectral imaging",

abstract = "The nanoscale morphology of solar cell materials strongly affects their performance. We report direct evidence for the existence of multiple length scales of heterogeneity in halide perovskites such as CsPbBr3 and CsPbBr3:KI. Contrary to the general notion of two distinct phases, our study suggests the presence of multiple phases in mixed halide perovskites. Highly spatially resolved (≈50 nm) cathodoluminescence maps reveal that the length scale of heterogeneity is composition dependent: smaller (≈ 200 nm) for CsPbBr3, and larger (≈500–1000 nm) for CsPbBr3:KI. Moreover, these nano-/micro-scale heterogeneities exist both laterally and vertically in mixed halides and correlate with high densities of carrier traps and fast trap-assisted recombination. The observed heterogeneities also lead to reduced power conversion efficiency of solar cells, higher hysteresis loss, and faster degradation. These insights argue for advanced nanoscale characterization of halide perovskites to guide reduction of heterogeneity and so improve device performance and stability.",

keywords = "Halide perovskites, Grain-to-grain inhomogeneity, Gradient in bandgap, Local strain, Local phase segregation",

author = "{Krishnan Jagadamma}, Lethy and P Edwards and R Martin and Arvydas Ruseckas and Samuel, {Ifor David William}",

note = "Funding: We are grateful for funding from the EPSRC under grant code EP/L017008/1. Dr. L. K. Jagadamma acknowledges support from a Marie Sk{\l}odowska-Curie Individual Fellowship (European Commission) (MCIF: No. 745776).",

year = "2021",

month = may,

day = "22",

doi = "10.1021/acsaem.0c03154",

language = "English",

volume = "4",

pages = "2707–2715",

journal = "ACS Applied Energy Materials",

issn = "2574-0962",

publisher = "American Chemical Society (ACS)",

number = "3",

}

TY - JOUR

T1 - Nanoscale heterogeneity in CsPbBr3 and CsPbBr3:KI perovskite films revealed by cathodoluminescence hyperspectral imaging

AU - Krishnan Jagadamma, Lethy

AU - Edwards, P

AU - Martin, R

AU - Ruseckas, Arvydas

AU - Samuel, Ifor David William

N1 - Funding: We are grateful for funding from the EPSRC under grant code EP/L017008/1. Dr. L. K. Jagadamma acknowledges support from a Marie Skłodowska-Curie Individual Fellowship (European Commission) (MCIF: No. 745776).

PY - 2021/5/22

Y1 - 2021/5/22

N2 - The nanoscale morphology of solar cell materials strongly affects their performance. We report direct evidence for the existence of multiple length scales of heterogeneity in halide perovskites such as CsPbBr3 and CsPbBr3:KI. Contrary to the general notion of two distinct phases, our study suggests the presence of multiple phases in mixed halide perovskites. Highly spatially resolved (≈50 nm) cathodoluminescence maps reveal that the length scale of heterogeneity is composition dependent: smaller (≈ 200 nm) for CsPbBr3, and larger (≈500–1000 nm) for CsPbBr3:KI. Moreover, these nano-/micro-scale heterogeneities exist both laterally and vertically in mixed halides and correlate with high densities of carrier traps and fast trap-assisted recombination. The observed heterogeneities also lead to reduced power conversion efficiency of solar cells, higher hysteresis loss, and faster degradation. These insights argue for advanced nanoscale characterization of halide perovskites to guide reduction of heterogeneity and so improve device performance and stability.

AB - The nanoscale morphology of solar cell materials strongly affects their performance. We report direct evidence for the existence of multiple length scales of heterogeneity in halide perovskites such as CsPbBr3 and CsPbBr3:KI. Contrary to the general notion of two distinct phases, our study suggests the presence of multiple phases in mixed halide perovskites. Highly spatially resolved (≈50 nm) cathodoluminescence maps reveal that the length scale of heterogeneity is composition dependent: smaller (≈ 200 nm) for CsPbBr3, and larger (≈500–1000 nm) for CsPbBr3:KI. Moreover, these nano-/micro-scale heterogeneities exist both laterally and vertically in mixed halides and correlate with high densities of carrier traps and fast trap-assisted recombination. The observed heterogeneities also lead to reduced power conversion efficiency of solar cells, higher hysteresis loss, and faster degradation. These insights argue for advanced nanoscale characterization of halide perovskites to guide reduction of heterogeneity and so improve device performance and stability.

KW - Halide perovskites

KW - Grain-to-grain inhomogeneity

KW - Gradient in bandgap

KW - Local strain

KW - Local phase segregation

U2 - 10.1021/acsaem.0c03154

DO - 10.1021/acsaem.0c03154

M3 - Article

SN - 2574-0962

VL - 4

SP - 2707

EP - 2715

JO - ACS Applied Energy Materials

JF - ACS Applied Energy Materials

IS - 3

ER -

Nanoscale heterogeneity in CsPbBr3 and CsPbBr3:KI perovskite films revealed by cathodoluminescence hyperspectral imaging

Abstract

Keywords

Access to Document

Fingerprint

Projects

H2020 MSCA - PHOTOPEROVSKITIES: H2020 MSCA Fellowship 2016 Lethy

Equipment Account: Characterisation and Manipulation of Advanced Functional Materials and their Interfaces at the Nanoscale

Datasets

Nanoscale heterogeneity in CsPbBr3 and CsPbBr3:KI perovskite films revealed by cat hodoluminescence hyperspectral imaging (dataset)

Cite this

Nanoscale heterogeneity in CsPbBr₃ and CsPbBr₃:KI perovskite films revealed by cathodoluminescence hyperspectral imaging