Subscriber access provided by UNIVERSITY OF ADELAIDE LIBRARIES
Article
Post-Synthetic, Reversible Cation Exchange Between Pb2+ and Mn2+ in Cesium Lead Chloride Perovskite Nanocrystals Di Gao, Bo Qiao, Zheng Xu, Dandan Song, Pengjie Song, Zhiqin Liang, Zhaohui Shen, Jingyue Cao, Junjie Zhang, and Suling Zhao J. Phys. Chem. C, Just Accepted Manuscript • DOI: 10.1021/acs.jpcc.7b06929 • Publication Date (Web): 28 Aug 2017 Downloaded from http://pubs.acs.org on August 29, 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.
The Journal of Physical Chemistry C 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 24
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
The Journal of Physical Chemistry
Post-Synthetic, Reversible Cation Exchange Between Pb2+ and Mn2+ in Cesium Lead Chloride Perovskite Nanocrystals Di Gao, ‡,a,b Bo Qiao,‡,a,b Zheng Xu,*,a,b Dandan Song,a,b Pengjie Song,a,b Zhiqin Liang,a,b Zhaohui Shen,a,b Jingyue Cao,a,b Junjie Zhang,a,b and Suling Zhao*,a,b a. Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University), Ministry of Education, Beijing 100044, China b. Institute of Optoelectronics Technology, Beijing Jiaotong University, Beijing 100044, China
ABSTRACT: CsPbX3 (X=Cl, Br, I) perovskite nanocrystals (NCs) are promising materials due to their excellent optoelectronic properties. In this work, we show a successful partial and reversible cation exchange reaction between Pb and Mn in both CsPbCl3 NCs and CsMnCl3 NCs systems to yield luminescent CsPb1-xMnxCl3 NCs. By adjusting the reaction time, the photoluminescence from the exciton emission of CsPbCl3 and the electron transition of Mn2+ can be tuned gradually. This work highlights the feasibility of a post-synthetic interconversion of Pb2+ and Mn2+ in cesium lead chloride perovskite nanocrystals, which enables a new strategy to reduce the toxicity and adjust the emissions of CsPbCl3 NCs. In the end, we also discuss the plausible mechanisms for cation exchange in perovskite materials.
ACS Paragon Plus Environment
1
The Journal of Physical Chemistry
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 24
INTRODUCTION Halide perovskites have attracted much attention and are a promising material for optoelectronic applications in the field of light-emitting diodes,1-7 photodetectors,8, 9 lasers,10, 11 solar cells12-15 and so forth due to their excellent optical properties.16-19 In the last few years, studies on halide perovskites have mainly focused on organic-inorganic hybrid perovskites.12, 13, 20, 21
Since Loredana Protesescu et al. first reported cesium lead halide, all inorganic perovskites
(CsPbX3 ， X=Cl, Br, I or a combination of both) with good crystallinity, narrow size distributions, narrow emission line widths and high photoluminescence quantum yields (up to 90%),16 the study of all inorganic perovskites has become a research hotspot. The synthetic protocols for CsPbX3 perovskites in several shapes, such as cubes,16,
22
nanowires,23,
24
and
nanoplatelets,25-27 are available. In addition, there was a series of studies on anion exchange28, 29 and Mn-doped CsPbX3 perovskites30-33 to tune the emission of prepared CsPbX3 as widely studied doped II-VI semiconductors.34-36 Although there are many advantages to the CsPbX3 perovskites, the toxicity of Pb is still a serious problem that needs to be solved. The bandgap engineering of lead halide perovskites is mainly at the synthesis stage, and techniques have included partially or completely substituting the cations (Sn37 or Mn30-33 instead of Pb and formamidium instead of MA15) or mixing different ratios of different halide salts in the reaction flask.28 Ion exchange has proven to be a highly useful method for the synthesis of new and functional nanostructures.38, 39 Cation exchange, a post-synthetic substitution reaction, is usually applicable to compound semiconductors.40 It has been widely used for the demands of the compositional modulation, shape engineering, and new optical and electronic properties41 of functional materials. Recently, Ward van der Stam et al. presented a post-synthetic cation exchange method to partially exchange Pb2+ ions in CsPbBr3
ACS Paragon Plus Environment
2
Page 3 of 24
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
The Journal of Physical Chemistry
perovskites with several other divalent cations (Sn2+, Cd2+, and Zn2+).42 The partial Pb2+ for M2+ exchange leads to a blueshift in the optical spectra while maintaining the high photoluminescence quantum yields (>50%), sharp absorption features, and narrow emission of the parent CsPbBr3 NCs. This work opens up new possibilities to engineer the properties of halide perovskite NCs after synthesis. CsPbCl3 perovskite is another kind of potential material recently synthesized for blue emission. Wenyong Liu et al. reported Mn2+-doped CsPbCl3 perovskites with low concentrations and realized emissions from both the host CsPbCl3 and Mn2+ ions at approximately 402 nm and 586 nm, respectively. In addition, the anion exchange between Cl- and Br- affords the opportunity to finely and reversibly tune the band gap of the perovskite NCs, which provides opportunity for application as dual-color emitters. The substitution ratio of Mn2+ is low (
