城戸・笹部・千葉研究室D3 鄭宇宏さん (Yu-Hong Cheng) と千葉貴之助教のGPC洗浄を用いたCs3Cu2I5ナノ結晶の高配向薄膜形成に関する論文がScientific Reports (IF: 4.380) に掲載されました。
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, and Junji Kido*
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.