Subscriber access provided by LONDON METROPOLITAN UNIV
Communication
Mixed-halide perovskites with stabilized bandgaps Zhengguo Xiao, Lianfeng Zhao, Nhu Tran, YunHui Lisa Lin, Scott H. Silver, Ross A. Kerner, Nan Yao, Antoine Kahn, Gregory D. Scholes, and Barry P. Rand Nano Lett., Just Accepted Manuscript • DOI: 10.1021/acs.nanolett.7b03179 • Publication Date (Web): 02 Oct 2017 Downloaded from http://pubs.acs.org on October 3, 2017
Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.
Nano Letters is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.
Page 1 of 21
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Nano Letters
Mixed-halide perovskites with stabilized bandgaps Zhengguo Xiao1, Lianfeng Zhao1, Nhu L. Tran2, Yunhui (Lisa) Lin1, Scott H. Silver1, Ross A. Kerner1, Nan Yao3, Antoine Kahn1, Gregory D. Scholes2, Barry P. Rand1,4*.
1
Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544,
United States 2
Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
3
Princeton Institute for Science and Technology of Materials, Princeton University, Princeton,
New Jersey 08544, United States 4
Andlinger Center for Energy and the Environment, Princeton University, Princeton, New Jersey
08544, United States
KEYWORDS: Mixed-halide perovskite, halide migration, phase separation, LEDs, solar cells.
ABSTRACT: One merit of organic-inorganic hybrid perovskites is their tunable bandgap by adjusting the halide stoichiometry, an aspect critical to their application in tandem solar cells, wavelength-tunable light emitting diodes (LEDs), and lasers. However, the phase separation of mixed-halide perovskites caused by light or applied bias results in undesirable recombination at iodide-rich domains, meaning open-circuit voltage (VOC) pinning in solar cells and infrared emission in LEDs. Here, we report an approach to suppress halide redistribution by selfassembled long-chain organic ammonium capping layers at nanometer-sized grain surfaces.
ACS Paragon Plus Environment
1
Nano Letters
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Page 2 of 21
Using the stable mixed-halide perovskite films, we are able to fabricate efficient and wavelengthtunable perovskite LEDs from infrared to green with high external quantum efficiencies of up to 5%, as well as linearly tuned VOC from 1.05 V to 1.45 V in solar cells.
The performances of metal halide perovskites-based devices have experienced consistent and rapid progress recently, both for solar cells1-3 and light emitting diodes (LEDs)4-10. Mixedhalide perovskites are particularly attractive, as they allow for bandgap tuning, necessary for making tandem solar cells and wavelength tunable LEDs and lasers11-16. However, mixed-halide perovskites such as methylammonium (MA) or formamidinium (FA) lead iodide/bromide (MAPb(I1-xBrx)3 or FAPb(I1-xBrx)3), have phase instability issues originating from differences in crystal structure between the I- and Br-perovskites17. This results in de-mixing of the halides for mid x values (0.2
