title: Thermally induced structural evolution and performance of mesoporous block copolymer-directed alumina perovskite solar cells.
abstract: Structure control in solution-processed hybrid perovskites is crucial to design and fabricate highly efficient solar cells. Here, we utilize in situ grazing incidence wide-angle X-ray scattering and scanning electron microscopy to investigate the structural evolution and film morphologies of methylammonium lead tri-iodide/chloride (CH3NH3PbI(3-x)Cl(x)) in mesoporous block copolymer derived alumina superstructures during thermal annealing. We show the CH3NH3PbI(3-x)Cl(x) material evolution to be characterized by three distinct structures: a crystalline precursor structure not described previously, a 3D perovskite structure, and a mixture of compounds resulting from degradation. Finally, we demonstrate how understanding the processing parameters provides the foundation needed for optimal perovskite film morphology and coverage, leading to enhanced block copolymer-directed perovskite solar cell performance.
authors.affiliation: Department of Materials Science and Engineering, ‡School of Chemical and Biomolecular Engineering, Cornell University , Ithaca, New York 14853, United States.
authors.forename: Kwan Wee
authors.initials: KW
authors.lastname: Tan
authors.forename: David T
authors.initials: DT
authors.lastname: Moore
authors.forename: Michael
authors.initials: M
authors.lastname: Saliba
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Sai
authors.forename: Lara A
authors.initials: LA
authors.lastname: Estroff
authors.forename: Tobias
authors.initials: T
authors.lastname: Hanrath
authors.forename: Henry J
authors.initials: HJ
authors.lastname: Snaith
authors.forename: Ulrich
authors.initials: U
authors.lastname: Wiesner
mesh_terms: D017610:Calcium Compounds / Q000737:chemistry*; D003460:Crystallization; D008855:Microscopy, Electron, Scanning; D010087:Oxides / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D012993:Solar Energy; D014025:Titanium / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D017610:Calcium Compounds; D010087:Oxides; D011108:Polymers; C059910:perovskite; D014025:Titanium