Atomic-scale microstructure of metal halide perovskite

DOI: 10.1126/science.abb5940

Authors: Mathias Uller Rothmann (University of Oxford) , Judy S. Kim (University of Oxford; Diamond Light Source; Rosalind Franklin Institute) , Juliane Borchert (University of Oxford) , Kilian B. Lohmann (University of Oxford) , Colum M. O'Leary (University of Oxford) , Alex A. Sheader (University of Oxford) , Laura Clark (University of Oxford) , Henry J. Snaith (University of Oxford) , Michael B. Johnston (University of Oxford) , Peter D. Nellist (University of Oxford) , Laura M. Herz (University of Oxford)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Science , VOL 370

State: Published (Approved)
Published: October 2020
Diamond Proposal Number(s): 21734

Abstract: Hybrid organic-inorganic perovskites have high potential as materials for solar energy applications, but their microscopic properties are still not well understood. Atomic-resolution scanning transmission electron microscopy has provided invaluable insights for many crystalline solar cell materials, and we used this method to successfully image formamidinium lead triiodide [CH(NH2)2PbI3] thin films with a low dose of electron irradiation. Such images reveal a highly ordered atomic arrangement of sharp grain boundaries and coherent perovskite/PbI2 interfaces, with a striking absence of long-range disorder in the crystal. We found that beam-induced degradation of the perovskite leads to an initial loss of formamidinium [CH(NH2)2+] ions, leaving behind a partially unoccupied perovskite lattice, which explains the unusual regenerative properties of these materials. We further observed aligned point defects and climb-dissociated dislocations. Our findings thus provide an atomic-level understanding of technologically important lead halide perovskites.

Diamond Keywords: Photovoltaics; Semiconductors

Subject Areas: Materials, Physics, Energy

Diamond Offline Facilities: Electron Physical Sciences Imaging Centre (ePSIC)
Instruments: E02-JEM ARM 300CF

Added On: 03/11/2020 09:54

Discipline Tags:

Surfaces Earth Sciences & Environment Sustainable Energy Systems Energy Physics Climate Change Hard condensed matter - structures Energy Materials Materials Science interfaces and thin films Perovskites Metallurgy

Technical Tags:

Microscopy Electron Microscopy (EM) Transmission Electron Microscopy (TEM)