skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: In situ investigation of halide incorporation into perovskite solar cells

Abstract

Abstract

Authors:
ORCiD logo; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1399354
Report Number(s):
NREL/JA-5K00-68970
Journal ID: ISSN 2159-6859; applab
DOE Contract Number:
AC36-08GO28308
Resource Type:
Journal Article
Resource Relation:
Journal Name: MRS Communications; Journal Volume: 7; Journal Issue: 03
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; perovskite; perovskite solar cells; water vapor; dry condition; film coverage

Citation Formats

Aguiar, Jeffery A., Alkurd, Nooraldeen R., Wozny, Sarah, Patel, Maulik K., Yang, Mengjin, Zhou, Weilie, Al-Jassim, Mowafak, Holesinger, Terry G., Zhu, Kai, and Berry, Joseph J. In situ investigation of halide incorporation into perovskite solar cells. United States: N. p., 2017. Web. doi:10.1557/mrc.2017.52.
Aguiar, Jeffery A., Alkurd, Nooraldeen R., Wozny, Sarah, Patel, Maulik K., Yang, Mengjin, Zhou, Weilie, Al-Jassim, Mowafak, Holesinger, Terry G., Zhu, Kai, & Berry, Joseph J. In situ investigation of halide incorporation into perovskite solar cells. United States. doi:10.1557/mrc.2017.52.
Aguiar, Jeffery A., Alkurd, Nooraldeen R., Wozny, Sarah, Patel, Maulik K., Yang, Mengjin, Zhou, Weilie, Al-Jassim, Mowafak, Holesinger, Terry G., Zhu, Kai, and Berry, Joseph J. Mon . "In situ investigation of halide incorporation into perovskite solar cells". United States. doi:10.1557/mrc.2017.52.
@article{osti_1399354,
title = {In situ investigation of halide incorporation into perovskite solar cells},
author = {Aguiar, Jeffery A. and Alkurd, Nooraldeen R. and Wozny, Sarah and Patel, Maulik K. and Yang, Mengjin and Zhou, Weilie and Al-Jassim, Mowafak and Holesinger, Terry G. and Zhu, Kai and Berry, Joseph J.},
abstractNote = {Abstract},
doi = {10.1557/mrc.2017.52},
journal = {MRS Communications},
number = 03,
volume = 7,
place = {United States},
year = {Mon Jul 10 00:00:00 EDT 2017},
month = {Mon Jul 10 00:00:00 EDT 2017}
}
  • Organic-inorganic perovskites have emerged as an important class of next generation solar cells due to their remarkably low cost, band gap, and sub-900 nm absorption onset. Here, we show a series of in situ observations inside electron microscopes and X-ray diffractometers under device-relevant synthesis conditions focused on revealing the crystallization process of the formamidinium lead-triiodide perovskite at the optimum temperature of 175 degrees C. Direct in situ observations of the structure and chemistry over relevant spatial, temporal, and temperature scales enabled identification of key perovskite formation and degradation mechanisms related to grain evolution and interface chemistry. The lead composition wasmore » observed to fluctuate at grain boundaries, indicating a mobile lead-containing species, a process found to be partially reversible at a key temperature of 175 degrees C. Using low energy electron microscopy and valence electron energy loss spectroscopy, lead is found to be bonded in the grain interior with iodine in a tetrahedral configuration. At the grain boundaries, the binding energy associated with lead is consequently shifted by nearly 2 eV and a doublet peak is resolved due presumably to a greater degree of hybridization and the potential for several different bonding configurations. At the grain boundaries there is adsorption of hydrogen and OH- ions as a result of residual water vapor trapped as a non-crystalline material during formation. Insights into the relevant formation and decomposition reactions of formamidinium lead iodide at low to high temperatures, observed metastabilities, and relationship with the photovoltaic performance were obtained and used to optimize device processing resulting in conversion efficiencies of up to 17.09% within the stability period of the devices.« less
  • Organic–inorganic perovskites have emerged as an important class of next generation solar cells due to their remarkably low cost, band gap, and sub-900 nm absorption onset. Here, we show a series of in situ observations inside electron microscopes and X-ray diffractometers under device-relevant synthesis conditions focused on revealing the crystallization process of the formamidinium lead-triiodide perovskite at the optimum temperature of 175 °C. Direct in situ observations of the structure and chemistry over relevant spatial, temporal, and temperature scales enabled identification of key perovskite formation and degradation mechanisms related to grain evolution and interface chemistry. The lead composition was observedmore » to fluctuate at grain boundaries, indicating a mobile lead-containing species, a process found to be partially reversible at a key temperature of 175 °C. Using low energy electron microscopy and valence electron energy loss spectroscopy, lead is found to be bonded in the grain interior with iodine in a tetrahedral configuration. At the grain boundaries, the binding energy associated with lead is consequently shifted by nearly 2 eV and a doublet peak is resolved due presumably to a greater degree of hybridization and the potential for several different bonding configurations. At the grain boundaries there is adsorption of hydrogen and OH¯ ions as a result of residual water vapor trapped as a non-crystalline material during formation. Lastly, insights into the relevant formation and decomposition reactions of formamidinium lead iodide at low to high temperatures, observed metastabilities, and relationship with the photovoltaic performance were obtained and used to optimize device processing resulting in conversion efficiencies of up to 17.09% within the stability period of the devices.« less