Elucidation of Photoluminescence Blinking Mechanism and Multiexciton Dynamics in Hybrid Organic-Inorganic Perovskite Quantum Dots.
Taehee KimSeok Il JungSujin HamHeejae ChungDongho KimPublished in: Small (Weinheim an der Bergstrasse, Germany) (2019)
Halide perovskites (ABX3 ) have emerged as promising materials in the past decade owing to their superior photophysical properties, rendering them potential candidates as solar cells, light-emitting diode displays, and lasing materials. To optimize their utilization into optoelectronic devices, fundamental understanding of the optical behaviors is necessary. To reveal the comprehensive structure-property relationship, CH3 NH3 PbBr3 (MAPbBr3 ) perovskite quantum dots (PQDs) of three different sizes are prepared by controlling the precipitation temperature. Photoluminescence (PL) blinking, a key process that governs the emission efficiency of the PQD materials, is investigated in detail by the time-resolved spectroscopic measurements of individual dots. The nature of the generated species in the course of blinking events is identified, and the mechanism governing the PL blinking is studied as a function of PQD sizes. Further, the practical applicability of MAPbBr3 PQDs is assessed by studying the multiexciton dynamics under high photoexcitation intensity under which most of the display devices work. Ultrafast transient absorption spectroscopy helped in uncovering the volume-dependent Auger recombination rates, which are further explored by comparing the early-time transitions related to surface trap states and higher band states.
Keyphrases
- solar cells
- quantum dots
- light emitting
- energy transfer
- sensitive detection
- room temperature
- high resolution
- solid state
- dna damage
- molecular docking
- dna repair
- high intensity
- genome wide
- molecular dynamics simulations
- dna methylation
- atomic force microscopy
- cerebral ischemia
- oxidative stress
- genetic diversity
- high speed
- climate change
- simultaneous determination
- walled carbon nanotubes