Cesium Lead Halide 페로브스카이트 양자점의 음이온 교환 반응 동역학

• Published in: Biuletyn Uniejowski Vol. 51; no. 5; pp. 257 - 262
• Main Authors: 이시맥(See Maek Lee), 정현성(Hyunsung Jung), 박운익(Woonik Park), 임현섭(Hyunseob Lim), 방지원(Jiwon Bang)
• Format: Journal Article
• Language: Korean
• Published: 한국표면공학회 2018
• Subjects: 기계공학; Anion exchange; Quantum dots; Cesium lead halide; Surface
• ISSN: 1225-8024; 2299-8403; 2288-8403
• DOI: 10.5695/JKISE.2018.51.5.257

Cesium lead halide perovskite quantum dots (QDs) have recently emerged as highly promising opto-electronic materials. Despite the relative facile anion exchange reactions in cesium lead halide perovskite QDs, in depth study of the anion exchange reactions such as reaction kinetics are required that can provide insight into the crystal transformation in the cesium lead halide perovskite QDs. Herein, we investigated the anion exchange reaction from $CsPbI_3$ QDs to $CsPbBr_3$ QDs with varying the particle size of the starting $CsPbI_3$ QDs. By characterizing the PL spectra in the anion exchange reaction process, we observed that discontinuous PL peak shifts during I-to-Br anion exchange reaction in starting $CsPbI_3$ QDs over a critical size. Origin of the discontinuous I-to-Br anion exchange kinetics are mainly due to thermodynamically unstable nature of the $CsPb(Br/I)_3$ alloy QDs.