Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403

공학

한국표면공학회지 (51권5호 257-262)

Anion Exchange Reaction Dynamics in Cesium Lead Halide Perovskite Quantum Dots

Cesium Lead Halide 페로브스카이트 양자점의 음이온 교환 반응 동역학

이시맥;정현성;박운익;임현섭;방지원;
Lee, See Maek;Jung, Hyunsung;Park, Woonik;Lim, Hyunseob;Bang, Jiwon;

한국세라믹기술원 전자융합소재본부 나노융합소재센터;전남대학교 화학과;
Korea Institute of Ceramic Engineering and Technology, Electronic Conversion Materials Division;Department of Chemistry, Chonnam National University (CNU);

DOI : 10.5695/JKISE.2018.51.5.257

Abstract

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.

Keywords

Cesium lead halide;Quantum dots;Anion exchange;Surface;