Gel permeation chromatography process for highly oriented Cs3Cu2I5 nanocrystal film

Yu-Hong Cheng; Rikuo Suzuki; Narumi Shinotsuka; Hinako Ebe; Naoaki Oshita; Ryohei Yamakado; Takayuki Chiba; Akito Masuhara; Junji Kido

doi:10.1038/s41598-022-08760-6

Gel permeation chromatography process for highly oriented Cs₃Cu₂I₅ nanocrystal film

Sci Rep. 2022 Mar 17;12(1):4620. doi: 10.1038/s41598-022-08760-6.

Authors

Yu-Hong Cheng¹, Rikuo Suzuki¹, Narumi Shinotsuka¹, Hinako Ebe¹, Naoaki Oshita², Ryohei Yamakado¹, Takayuki Chiba³, Akito Masuhara², Junji Kido⁴

Affiliations

¹ Graduate School of Organic Materials Science, Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata, 992-8510, Japan.
² Graduate School of Science and Engineering, Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata, 992-8510, Japan.
³ Graduate School of Organic Materials Science, Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata, 992-8510, Japan. T-chiba@yz.yamagata-u.ac.jp.
⁴ Graduate School of Organic Materials Science, Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata, 992-8510, Japan. kid@yz.yamagata-u.ac.jp.

Abstract

The emergence of green materials has attracted considerable attention in the field of optoelectronics. Copper-based lead-free metal halide (with a near-unity quantum yield) obtained from Cs₃Cu₂I₅ nanocrystals (NCs) can exhibit blue emission with a wavelength of 440 nm and provide outstanding stability for various applications. However, in practical applications, colloidal dispersion purity and film quality are inadequate toward a high-performance device. In this study, antisolvent-free gel permeation chromatography is used to purify Cs₃Cu₂I₅ NCs. The purified Cs₃Cu₂I₅ NCs exhibit a high photoluminescent quantum yield and provide a highly oriented single-crystal film. Density functional theory calculation results indicate that the iodide-rich surface in the NCs makes them highly stable. In addition, it has been demonstrated for the first time that the mixture of polymethyl methacrylate (PMMA) and Cs₃Cu₂I₅ NCs has waterproofing capabilities. The composite film consisting of Cs₃Cu₂I₅ NCs and PMMA can survive in water for several days. This result opens up more possibilities for the application of these green material.