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Title: Determination of the True Lateral Grain Size in Organic–Inorganic Halide Perovskite Thin Films

Here, methylammonium lead iodide (MAPbI 3) thin films were examined via piezoresponse force microscopy (PFM) and nanoindentation (NI) to determine if long-range atomic order existed across the full width and depth of the apparent grains. And from the PFM, the piezoelectric response of the films was strongly correlated with low-index planes of the crystal structure and ferroelastic domains in macroscale solution-grown MAPbI 3 crystals, which implied long-range order near the top surface. From the NI, it was found that the induced cracks were straight and extended across the full width of the apparent grains, which indicated that the long-range order was not limited to the near-surface region, but extended through the film thickness. Interestingly, the two MAPbI 3 processes examined resulted in subtle differences in the extracted electro-mechanical and fracture properties, but exhibited similar power conversion efficiencies of >17% in completed devices.
 [1] ;  [2] ;  [3] ;  [3] ; ORCiD logo [3] ;  [4] ;  [1] ; ORCiD logo [1]
  1. National Inst. of Standards and Technology (NIST), Boulder, CO (United States). Material Measurement Lab.
  2. Univ. of Colorado, Boulder, CO (United States). Dept. of Mechanical Engineering
  3. National Renewable Energy Lab. (NREL), Golden, CO (United States). Chemistry and Nanoscience Center
  4. Univ. of Colorado, Boulder, CO (United States). Dept. of Mechanical Engineering, Materials Science Program
Publication Date:
Report Number(s):
Journal ID: ISSN 1944-8244; TRN: US1702021
Grant/Contract Number:
AC36-08GO28308; T32AG000279; 1338154
Accepted Manuscript
Journal Name:
ACS Applied Materials and Interfaces
Additional Journal Information:
Journal Volume: 9; Journal Issue: 39; Journal ID: ISSN 1944-8244
American Chemical Society (ACS)
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S); National Institutes of Health (NIH); National Science Foundation (NSF)
Country of Publication:
United States
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; ferroelastic domains; grain size; nanoindentation; perovskites; photovoltaic devices; piezoresponse force microscopy
OSTI Identifier: