Wide and Tunable Bandgap MAPbBr3−xClx Hybrid Perovskites with Enhanced Phase Stability: In Situ Investigation and Photovoltaic Devices. Issue 4 (7th March 2021)

• Record Type: Journal Article
• Authors: Tang, Ming-Chun; Dang, Hoang X.; Lee, Sehyun; Barrit, Dounya; Munir, Rahim; Wang, Kai; Li, Ruipeng; Smilgies, Detlef-M.; De Wolf, Stefaan; Kim, Dong-Yu; Anthopoulos, Thomas D.; Amassian, Aram
• Is Part Of: Solar RRL. Volume 5:Issue 4(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-03-07
• Subjects: hybrid perovskite solar cells -- in situ UV–Vis absorbance -- phase stability -- time-resolved grazing incidence wide-angle X-ray scattering -- wide bandgap -- tunable bandgap; Solar energy -- Periodicals; Photovoltaic power generation -- Periodicals; Solar energy -- Research -- Periodicals; Photovoltaic power generation -- Research -- Periodicals; Periodicals; 333.7923
• DOI: 10.1002/solr.202000718
• Languages: English
• ISSNs: 2367-198X

Abstract

Abstract : The current understanding of the crystallization, morphology evolution, and phase stability of wide‐bandgap hybrid perovskite thin films is very limited, as much of the community's focus is on lower bandgap systems. Herein, the crystallization behavior and film formation of a wide and tunable bandgap MAPbBr3− x Cl x system are investigated, and its formation and phase stability are contrasted to the classical MAPbI3− x Br x case. A multiprobe in situ characterization approach consisting of synchrotron‐based grazing incidence wide‐angle X‐ray scattering and laboratory‐based time‐resolved UV–Vis absorbance measurements is utilized to show that all wide‐bandgap perovskite compositions of MAPbBr3− x Cl x studied (0 < x < 3) crystallize the same way: the perovskite phase forms directly from the colloidal sol state and forms a solid film in the cubic structure. This results in significantly improved alloying and phase stability of these compounds compared with MAPbI3− x Br x systems. The phase transformation pathway is direct and excludes solvated phases, in contrast to methylammonium lead iodide (MAPbI3 ). The films benefit from antisolvent dripping to overcome the formation of discontinuous layers and enable device integration. Pin‐hole‐free MAPbBr3− x Cl x hybrid perovskite thin films with a tunable bandgap are, thus, integrated into working single‐junction solar cell devices and achieve a tunable open‐circuit voltage as high as 1.6 V. Abstract : In situ diagnostics (X‐ray scattering and optical absorbance) reveal nearly identical crystallization behaviors of all MAPbBr3− x Cl x perovskite alloys and pure halide systems from a dimethyl sulfoxide (DMSO) solution, which is vastly different from methylammonium lead iodide (MAPbI3 ). The similarities in the structure and the phase transformation pathway promote halide homogeneity in the mixed‐halide perovskite alloys.