Journal
NANO LETTERS
Volume 15, Issue 7, Pages 4799-4807Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.nanolett.5b01917
Keywords
Methylammonium-lead halide perovskite; cathodoluminescence; nanoimaging; surface defects; nonradiative recombination; photovoltaics
Categories
Funding
- Laboratory Directed Research and Development program at NREL
- Department of Energy [DE-AC36-08G028308]
- Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy [DE-AC02-05CH11231]
- NSF [DGE 1106400]
Ask authors/readers for more resources
We reveal substantial luminescence yield heterogeneity among individual subdiffraction grains of high-performing methylammonium lead halide perovskite films by using high-resolution cathodoluminescence microscopy. Using considerably lower accelerating voltages than is conventional in scanning electron microscopy, we image the electron beam-induced luminescence of the films and statistically characterize the depth-dependent role of defects that promote nonradiative recombination losses. The highest variability in the luminescence intensity is observed at the exposed grain surfaces, which we attribute to surface defects. By probing deeper into the film, it appears that bulk defects are more homogeneously distributed. By identifying the origin and variability of a surface-specific loss mechanism that deleteriously impacts device efficiency, we suggest that producing films homogeneously composed of the highest-luminescence grains found in this study could result in a dramatic improvement of overall device efficiency. We also show that although cathodoluminescence microscopy is generally used only to image inorganic materials it can be a powerful tool to investigate radiative and nonradiative charge carrier recombination on the nanoscale in organic-inorganic hybrid materials.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available