Performance Enhanced Light-Emitting Diodes Fabricated from Nanocrystalline CsPbBr3 with In Situ Zn2+ Addition
| Autor: | Alasdair A. M. Brown, Suan Hui Pu, Timothy J. White, Subodh Mhaisalkar, Benjamin E. Griffith, John V. Hanna, Mohammed S. Ansari, Annalisa Bruno, Parth Vashishtha, Yanan Fang, Thomas J. N. Hooper |
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| Přispěvatelé: | School of Materials Science and Engineering, School of Physical and Mathematical Sciences, Energy Research Institute @ NTU (ERI@N) |
| Rok vydání: | 2020 |
| Předmět: |
Light-emitting Diodes
All-inorganic Perovskite Nanocrystals Materials science Materials [Engineering] business.industry chemistry.chemical_element Halide Nanocrystalline material Electronic Optical and Magnetic Materials law.invention chemistry Solid-state nuclear magnetic resonance Nanocrystal law Caesium Materials Chemistry Electrochemistry Optoelectronics Thermal stability business Perovskite (structure) Light-emitting diode |
| Zdroj: | ACS Applied Electronic Materials. 2:4002-4011 |
| ISSN: | 2637-6113 |
| DOI: | 10.1021/acsaelm.0c00827 |
| Popis: | Inorganic cesium lead halide perovskite nanocrystals are promising materials for optoelectronic applications as they exhibit high thermal stability alongside precise color tunability and high color purity; however, their optical properties are degraded by surface defects. This work demonstrates a room temperature synthesis of CsPbBr3 nanocrystals facilitating in situ surface passivation via the incorporation of Zn2+ cations. The facile incorporation ZnBr2 into the precursor solution facilitates Zn2+ and Br− substitution into the nanocrystal surface/subsurface layers to induce passivation of existing Pb2+ and Br– vacancies and increase the photoluminescence quantum yield from ∼48 to 86%. The XPS and solid-state 1H MAS NMR techniques show that the key modification is a reduction of the octylamine:oleic acid ratio leading to a near-neutral surface charge; this is accompanied by the appearance of larger nanosheets and nanowires observed by quantitative powder XRD and HR-TEM. The suitability of these perovskite nanocrystals for electrically driven applications was confirmed by the fabrication of light-emitting diodes, which demonstrate that the in situ Zn2+ passivation strategy enhanced the external quantum efficiency by ∼60%. National Research Foundation (NRF) PV acknowledges a Presidential Postdoctoral Fellowship from Nanyang Technological University (NTU), Singapore via grant 04INS000581C150OOE01. We acknowledge financial support from the Singapore National Research Foundation, Prime Minister’s Office, through the Competitive Research Program (CRP Award No. NRF-CRP14-2014-03). The authors would like to acknowledge the Facility for Analysis, Characterization, Testing and Simulation (FACTS) at NTU, Singapore, for use of their electron microscopy and X-ray diffraction facilities. We would also like to acknowledge the NTU Center of High Field NMR Spectroscopy and Imaging for the use of their NMR facilities. The authors would also like to thank Prof. Nripan Mathews and Dr. Nur Fadilah Jamaludin for the valuable discussion, Mr. Sai S. H. Dintakurti for discussions with aspects of the crystallographic analysis and Mr. Gautam V. Nutan for assistance with the XPS measurements. JVH acknowledges financial support for the solid state NMR instrumentation at Warwick used in this research which was funded by EPSRC (grants EP/M028186/1 and EP/K024418/1), the University of Warwick, and the Birmingham Science City AM1 and AM2 projects which were supported by Advantage West Midlands (AWM) and the European Regional Development Fund (ERDF). AAMB acknowledges the Tizard studentship from the Faculty of Engineering and Physical Sciences at University of Southampton. |
| Databáze: | OpenAIRE |
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