Highly photo-stable CsPbI3 perovskite quantum dots (PeQDs) were prepared using thiol as an exchanged ligand. Among the CsPbX3 PeQDs, CsPbI3 with common capping ligands such as oleic acid (OA) and oleylamine (OLA) was particularly unstable and the optical properties were readily degraded because of its structural instability. To overcome these problems, thiol (–SH) as an exchanged ligand was used to stabilize the structure and could maintain the structural and optical properties. The synthesized CsPbI3 exhibited highly improved photo-stability under ultraviolet (365 nm) irradiation by ligand exchange from OA and OLA to thiol. As an application, perovskite films were fabricated using the PeQDs and a cyclic olefin copolymer (COC). The thiol-treated PeQD films exhibited higher stability than the untreated films under irradiation with a blue light-emitting diode (LED).
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science ICT and Future Planning (no. 2014R1A5A1009799) and Nano-Material Technology Development Program (2017M3A7B4041696), Republic of Korea.This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science ICT and Future Planning (no. 2014R1A5A1009799 ) and Nano-Material Technology Development Program ( 2017M3A7B4041696 ), Republic of Korea.
