Water mediated synthesis of phase-stable red-emitting CsPbI3 nanocrystals

• Published in: Journal of materials research Vol. 36; no. 9; pp. 1824 - 1834
• Main Authors: Xu, Zhuhua, He, Miao, Zhang, Siwei, Li, Jingzhou, Lv, Yanfei, Zhao, Shichao, Wei, Guodan
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 14.05.2021; Springer Nature B.V
• Subjects: Absorption; Applied and Technical Physics; Aqueous solutions; Biomaterials; Chemistry and Materials Science; Inorganic Chemistry; Materials Engineering; Materials research; Materials Science; Moisture absorption; Moisture effects; Nanocrystals; Nanotechnology; Perovskites; Photoluminescence; Sodium thiosulfate; Solvents; Spectra; Spin coating; Temperature dependence; Water; Nanoscale; Perovskites; Devices; Optical properties
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/s43578-021-00118-4

With the unusual luminescence and photoconductive characteristics, the CsPbI 3 perovskite has attracted a lot of attention in the field of material synthesis and device fabrication. The general synthesis methods of CsPbI 3 are through the organic solvent spin-coating and heating. To avoid the toxic organic solvent, herein we reported the organic solvent-free synthesis method. The precursors PbI 2 and CsI were solved in aqueous solution and heated to form the CsPbI 3 perovskite. It is found that the Na 2 S 2 O 3 as a reaction additive could enhance the CsPbI 3 crystal quality and the synthesis temperature could be lowered down to 80 °C. The content of Pb 2+ was increased by combination with S 2 O 3 2− in Na 2 S 2 O 3 aqueous solution. The photoluminescence (PL) spectra showed the PL of CsPbI 3 perovskite can disappear/recover through absorbing/removing to moisture, respectively. By integrating the CsPbI 3 film to the blue diode, we obtained an LED device. Our method provides an innovative strategy to prepare CsPbI 3 perovskites in aqueous solution. Graphic abstract We reported water mediated synthesis of phase-stable red-emitting CsPbI 3 nanocrystals at the reaction temperature as low as 80 °C with the introduced Na 2 S 2 O 3 additive. The photoluminescence (PL) spectra with could be fully recovered after continuous cycles of moisture absorption and removal. The temperature-dependence PL spectra demonstrated that the CsPbI 3 prepared in the presence of Na 2 S 2 O 3 exhibited the better PL properties and crystal quality compared with that in the absence of Na 2 S 2 O 3 .