@inproceedings{5357b806d7654bdab37fbbdd7aaaad3f,
title = "Extracting optical bandgaps from luminescence images of perovskite solar cells",
abstract = "We report a camera-based method to capture optical bandgap images of perovskite solar cells (PSCs). It is fast and non-destructive. It can also provide micron-scale spatial resolution. This imaging technique utilizes well-defined and relatively symmetrical band-to-band luminescence spectra emitted from perovskite materials. Their spectra can be fitted with Gaussian functions whose peak locations are similar to absorption thresholds and thus represent the material optical bandgaps. We apply the technique to resolve relative variations in optical bandgaps across various PSCs, and to show optical bandgap inhomogeneity within the same device due to material degradation and impurities. Degradation and impurities were found to both cause optical bandgap shifts inside the materials. Our results are independently confirmed with photoluminescence and absorption spectroscopy.",
keywords = "bandgap, imaging, luminescence, perovskite, photovolta-ics",
author = "Nguyen, {Hieu T.} and Boyi Chen and Jun Peng and Heping Shen and The Duong and Daniel Walter and Steve Johnston and Al-Jassim, {Mowafak M.} and Weber, {Klaus J.} and White, {Thomas P.} and Catchpole, {Kylie R.} and Daniel MacDonald",
note = "Publisher Copyright: {\textcopyright} 2019 IEEE.; 46th IEEE Photovoltaic Specialists Conference, PVSC 2019 ; Conference date: 16-06-2019 Through 21-06-2019",
year = "2019",
month = jun,
doi = "10.1109/PVSC40753.2019.8981346",
language = "English",
series = "Conference Record of the IEEE Photovoltaic Specialists Conference",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
pages = "630--633",
booktitle = "2019 IEEE 46th Photovoltaic Specialists Conference, PVSC 2019",
address = "United States",
}