Heterogeneous post-passivation of inorganic cesium lead halide perovskite quantum dots for efficient electroluminescent devices
- 21 March 2021
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Journal of Materials Chemistry C
- Vol. 9 (11), 3978-3986
- https://doi.org/10.1039/d0tc05856d
Abstract
A heterogeneous post-passivation process has been demonstrated by using formamidinium bromide (FABr) to compensate the surface bromo vacancy of inorganic cesium lead halide perovskite quantum dots (QDs). Benefitting from its limited solubility, the passivation is anticipated to happen in a two-phase heterogeneous mixture, and excess FABr can be easily removed using a polytetrafluoroethylene (PTFE) syringe filter before device fabrication. This is quite different from didodecyldimethylammonium bromide (DDAB)-based homogeneous post-passivation, where a large amount of DDAB residue is still left in the spin-coated film. Consequently, a more favorable electrical behavior is observed in FABr passivation compared to that in the DDAB one, although they both show comparable improved photoluminescence quantum yields due to bromo compensation. The corresponding perovskite quantum dots light-emitting diodes with FABr-treated green-emitting CsPbBr3 QDs achieve a promising external quantum efficiency (EQE) of 7.94% and luminance of 14 790 cd m(-2), much higher than those of the pristine (1.78%, 4640 cd m(-2)) and the DDAB-treated samples (3.91%, 167 cd m(-2)). This methodology is also suitable for the surface defect passivation of blue-emitting CsPbBr1.3Cl1.7 and red-emitting CsPbBr1I2 QDs. The results clearly highlight that heterogeneous post-passivation can boost the photoluminescence and electroluminescence performance of inorganic cesium lead halide perovskite QDs simultaneously.Funding Information
- National Natural Science Foundation of China (51703223, 51873205)
- National Key Research and Development Program of China (2016YFB0401301)
This publication has 32 references indexed in Scilit:
- Surface Termination of CsPbBr3 Perovskite Quantum Dots Determined by Solid-State NMR SpectroscopyJournal of the American Chemical Society, 2020
- Surface Halogen Compensation for Robust Performance Enhancements of CsPbX3 Perovskite Quantum DotsAdvanced Optical Materials, 2019
- Versatile Defect Passivation Methods for Metal Halide Perovskite Materials and their Application to Light‐Emitting DevicesAdvanced Materials, 2019
- Design Principles for Trap-Free CsPbX3 Nanocrystals: Enumerating and Eliminating Surface Halide Vacancies with Softer Lewis BasesJournal of the American Chemical Society, 2018
- All-Inorganic Metal Halide Perovskite Nanocrystals: Opportunities and ChallengesACS Central Science, 2018
- Surface Chemistry of All Inorganic Halide Perovskite Nanocrystals: Passivation Mechanism and StabilityAdvanced Materials Interfaces, 2018
- Genesis, challenges and opportunities for colloidal lead halide perovskite nanocrystalsNature Materials, 2018
- Highly Dynamic Ligand Binding and Light Absorption Coefficient of Cesium Lead Bromide Perovskite NanocrystalsACS Nano, 2016
- Nanocrystals of Cesium Lead Halide Perovskites (CsPbX3, X = Cl, Br, and I): Novel Optoelectronic Materials Showing Bright Emission with Wide Color GamutNano Letters, 2015
- Hybrid perovskites for photovoltaics: Insights from first principlesPhysical Review B, 2014