title: Crystallization kinetics of organic-inorganic trihalide perovskites and the role of the lead anion in crystal growth.
abstract: 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.
authors.affiliation: Department of Materials Science and Engineering, Cornell University , Ithaca, New York 14853, United States.
authors.forename: David T
authors.initials: DT
authors.lastname: Moore
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Sai
authors.forename: Kwan W
authors.initials: KW
authors.lastname: Tan
authors.forename: Detlef-M
authors.initials: DM
authors.lastname: Smilgies
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Henry J
authors.initials: HJ
authors.lastname: Snaith
authors.forename: Ulrich
authors.initials: U
authors.lastname: Wiesner
authors.forename: Lara A
authors.initials: LA
authors.lastname: Estroff
mesh_terms: D000838:Anions; D017610:Calcium Compounds / Q000737:chemistry*; D003460:Crystallization; D006219:Halogens / Q000737:chemistry*; D007287:Inorganic Chemicals / Q000737:chemistry*; D007700:Kinetics; D009930:Organic Chemicals / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D000838:Anions; D017610:Calcium Compounds; D006219:Halogens; D007287:Inorganic Chemicals; D009930:Organic Chemicals; D010087:Oxides; C059910:perovskite; D014025:Titanium