Crystallization Kinetics of Organic–Inorganic Trihalide Perovskites and the Role of the Lead Anion in Crystal Growth

Moore, David T.; Sai, Hiroaki; Tan, Kwan W.; Smilgies, Detlef-M.; Zhang, Wei; Snaith, Henry J.; Wiesner, Ulrich; Estroff, Lara A.

Crystallization Kinetics of Organic–Inorganic Trihalide Perovskites and the Role of the Lead Anion in Crystal Growth

Type

Article

Authors

Moore, David T.
Sai, Hiroaki
Tan, Kwan W.
Smilgies, Detlef-M.

Zhang, Wei

Snaith, Henry J.
Wiesner, Ulrich
Estroff, Lara A.

KAUST Grant Number

KUS-C1-018-02

Online Publication Date

2015-02-09

Print Publication Date

2015-02-18

Date

2015-02-09

Abstract

© 2015 American Chemical Society. Methylammonium lead halide perovskite solar cells continue to excite the research community due to their rapidly increasing performance which, in large part, is due to improvements in film morphology. The next step in this progression is control of the crystal morphology which requires a better fundamental understanding of the crystal growth. In this study we use in situ X-ray scattering data to study isothermal transformations of perovskite films derived from chloride, iodide, nitrate, and acetate lead salts. Using established models we determine the activation energy for crystallization and find that it changes as a function of the lead salt. Further analysis enabled determination of the precursor composition and showed that the primary step in perovskite formation is removal of excess organic salt from the precursor. This understanding suggests that careful choice of the lead salt will aid in controlling crystal growth, leading to superior films and better performing solar cells.

Citation

Moore DT, Sai H, Tan KW, Smilgies D-M, Zhang W, et al. (2015) Crystallization Kinetics of Organic–Inorganic Trihalide Perovskites and the Role of the Lead Anion in Crystal Growth. Journal of the American Chemical Society 137: 2350–2358. Available: http://dx.doi.org/10.1021/ja512117e.

Acknowledgements

The authors acknowledge financial support from the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award DE-SC0010560. K.W.T. gratefully acknowledges the Singapore Energy Innovation Program Office for a National Research Foundation graduate fellowship. This work made use of the research facilities of the Cornell Center for Materials Research (CCMR) with support from the NSF Materials Research Science and Engineering Centers (MRSEC) program (DMR-1120296), Cornell High Energy Synchrotron Source (CHESS) which is supported by the NSF and the NIH/National Institute of General Medical Sciences under NSF awards DMR-0936384 and DMR-1332208, and the KAUST-Cornell Center for Energy and Sustainability supported by Award KUS-C1-018-02, made by King Abdullah University of Science and Technology (KAUST). W.Z. and H.J.S thank the EPSRC Supergen, ERC Hyper Project, for financial support. The authors acknowledge the use of Fit2D for WAXS data analysis and thank the author, A. P. Hammersley, and ESRF, for its development and free use. The authors gratefully acknowledge T. Scott, M. Koker, and R. Li of Cornell University for kind experimental assistance.