Structural Origins of Light-Induced Phase Segregation in Organic-Inorganic Halide Perovskite Photovoltaic Materials

Author(s):Show less -

Beal, Rachel E. ^{[1, 2]} ; Hagstrom, Nanna Zhou ^{[3, 2]} ; Barrier, Julien ^{[2, 4]} ; Gold-Parker, Aryeh ^{[5, 2]} ; Prasanna, Rohit ^[1] ; Bush, Kevin A. ^[1] ; Passarello, Donata ^[2] ; Schelhas, Laura T. ^[6] ; Bruning, Karsten ^[2] ; Tassone, Christopher J. ^[2] ; Steinruck, Hans-Georg ^[2] ; McGehee, Michael D. ^[7] ; Toney, Michael F. ^[2] ; Nogueira, Ana Flavia ^{[2, 8]}

Affiliation

^[1] Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 - USA

^[2] SLAC Natl Accelerator Lab, SSRL Mat Sci Div, Menlo Pk, CA 94025 - USA

^[3] Stockholm Univ, Dept Phys, S-10691 Stockholm - Sweden

^[4] ESPCI Paris, Ecole Super Phys & Chim Ind, F-75005 Paris - France

^[5] Stanford Univ, Dept Chem, Stanford, CA 94305 - USA

^[6] SLAC Natl Accelerator Lab, Appl Energy Div, Menlo Pk, CA 94025 - USA

^[7] Univ Colorado, Dept Chem & Biol Engn, Boulder, CO 80309 - USA

^[8] Univ Estadual Campinas, Chem Inst, Lab Nanotecnol & Energia Solar, POB 6154, Campinas, SP - Brazil

• Document type: Journal article
• Source: MATTER; v. 2, n. 1, p. 207-219, JAN 8 2020.
• Web of Science Citations: 2

Abstract

Organic-inorganic metal-halide perovskite materials offer a promising route to reducing the dollars-per-watt cost of solar energy due to their good optoelectronic properties and facile, scalable processing. Compositional tuning allows for the preparation of absorbers with band gaps tailor-made for specific tandem and single-junction applications, but photoinduced phase segregation in mixed-halide materials leads to the formation of low-band-gap regions that reduce the voltage of devices. This work explores the structural origins of photoinduced phase segregation in FA(y)Cs(1-y)Pb(BrxI1-x)(3) perovskite alloys. We use synchrotron X- ray diffraction to map the solvus between the cubic and cubic-tetragonal mixed-phase region and time-dependent photoluminescence to assess stability under illumination. We show that the correlation between crystallographic phase and phase-segregation behavior is imperfect, so phase is not the sole determinant of optical stability. Instead, we consider several possible mechanisms that could underlie the dependence of optical stability on perovskite composition. (AU)

• FAPESP's process: 16/21426-4 - Understanding the impact of the preparation conditions upon the formation of perovskite materials applied to solar cells
• Grantee: Ana Flávia Nogueira
• Support Opportunities: Scholarships abroad - Research