Cd-free Cu-doped ZnInS/ZnS core/shell nanocrystals : controlled synthesis and photophysical properties
Here, we report efficient composition-tunable Cu-doped ZnInS/ZnS (core and core/shell) colloidal nanocrystals (CNCs) synthesized by using a colloidal non-injection method. The initial precursors for the synthesis were used in oleate form rather than in powder form, resulting in a nearly defect-free...
| Main Authors: | , , , , , , |
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| Format: | Journal Article |
| Language: | English |
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2018
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| Online Access: | https://hdl.handle.net/10356/86304 http://hdl.handle.net/10220/45237 |
| _version_ | 1811678208780664832 |
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| author | Kaur, Manpreet Sharma, Ashma Olutas, Murat Erdem, Onur Kumar, Akshay Sharma, Manoj Demir, Hilmi Volkan |
| author2 | School of Electrical and Electronic Engineering |
| author_facet | School of Electrical and Electronic Engineering Kaur, Manpreet Sharma, Ashma Olutas, Murat Erdem, Onur Kumar, Akshay Sharma, Manoj Demir, Hilmi Volkan |
| author_sort | Kaur, Manpreet |
| collection | NTU |
| description | Here, we report efficient composition-tunable Cu-doped ZnInS/ZnS (core and core/shell) colloidal nanocrystals (CNCs) synthesized by using a colloidal non-injection method. The initial precursors for the synthesis were used in oleate form rather than in powder form, resulting in a nearly defect-free photoluminescence (PL) emission. The change in Zn/In ratio tunes the percentage incorporation of Cu in CNCs. These highly monodisperse Cu-doped ZnInS CNCs having variable Zn/In ratios possess peak emission wavelength tunable from 550 to 650 nm in the visible spectrum. The quantum yield (QY) of these synthesized Cd-free CNCs increases from 6.0 to 65.0% after coating with a ZnS shell. The CNCs possessing emission from a mixed contribution of deep trap and dopant states to only dominant dopant-related Stokes-shifted emission are realized by a careful control of stoichiometric ratio of different reactant precursors during synthesis. The origin of this shift in emission was understood by using steady state and time-resolved fluorescence (TRF) spectroscopy studies. As a proof-of-concept demonstration, these blue excitable Cu-doped ZnInS/ZnS CNCs have been integrated with commercial blue LEDs to generate white-light emission (WLE). The suitable combination of these highly efficient doped CNCs results led to a Commission Internationale de l’Enclairage (CIE) color coordinates of (0.33, 0.31) at a color coordinate temperature (CCT) of 3694 K, with a luminous efficacy of optical radiation (LER) of 170 lm/Wopt and a color rendering index (CRI) of 88. |
| first_indexed | 2024-10-01T02:49:37Z |
| format | Journal Article |
| id | ntu-10356/86304 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T02:49:37Z |
| publishDate | 2018 |
| record_format | dspace |
| spelling | ntu-10356/863042020-06-01T10:01:38Z Cd-free Cu-doped ZnInS/ZnS core/shell nanocrystals : controlled synthesis and photophysical properties Kaur, Manpreet Sharma, Ashma Olutas, Murat Erdem, Onur Kumar, Akshay Sharma, Manoj Demir, Hilmi Volkan School of Electrical and Electronic Engineering School of Materials Science & Engineering School of Physical and Mathematical Sciences LUMINOUS! Centre of Excellence for Semiconductor Lighting and Displays Cadmium Free Colloidal Quantum Dots Here, we report efficient composition-tunable Cu-doped ZnInS/ZnS (core and core/shell) colloidal nanocrystals (CNCs) synthesized by using a colloidal non-injection method. The initial precursors for the synthesis were used in oleate form rather than in powder form, resulting in a nearly defect-free photoluminescence (PL) emission. The change in Zn/In ratio tunes the percentage incorporation of Cu in CNCs. These highly monodisperse Cu-doped ZnInS CNCs having variable Zn/In ratios possess peak emission wavelength tunable from 550 to 650 nm in the visible spectrum. The quantum yield (QY) of these synthesized Cd-free CNCs increases from 6.0 to 65.0% after coating with a ZnS shell. The CNCs possessing emission from a mixed contribution of deep trap and dopant states to only dominant dopant-related Stokes-shifted emission are realized by a careful control of stoichiometric ratio of different reactant precursors during synthesis. The origin of this shift in emission was understood by using steady state and time-resolved fluorescence (TRF) spectroscopy studies. As a proof-of-concept demonstration, these blue excitable Cu-doped ZnInS/ZnS CNCs have been integrated with commercial blue LEDs to generate white-light emission (WLE). The suitable combination of these highly efficient doped CNCs results led to a Commission Internationale de l’Enclairage (CIE) color coordinates of (0.33, 0.31) at a color coordinate temperature (CCT) of 3694 K, with a luminous efficacy of optical radiation (LER) of 170 lm/Wopt and a color rendering index (CRI) of 88. Published version 2018-07-25T08:39:15Z 2019-12-06T16:20:03Z 2018-07-25T08:39:15Z 2019-12-06T16:20:03Z 2018 Journal Article Kaur, M., Sharma, A., Olutas, M., Erdem, O., Kumar, A., Sharma, M., et al. (2018). Cd-free Cu-doped ZnInS/ZnS core/shell nanocrystals : controlled synthesis and photophysical properties. Nanoscale Research Letters, 13, 182-. 1931-7573 https://hdl.handle.net/10356/86304 http://hdl.handle.net/10220/45237 10.1186/s11671-018-2599-x en Nanoscale Research Letters © 2018 The Author(s). Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. 11 p. application/pdf |
| spellingShingle | Cadmium Free Colloidal Quantum Dots Kaur, Manpreet Sharma, Ashma Olutas, Murat Erdem, Onur Kumar, Akshay Sharma, Manoj Demir, Hilmi Volkan Cd-free Cu-doped ZnInS/ZnS core/shell nanocrystals : controlled synthesis and photophysical properties |
| title | Cd-free Cu-doped ZnInS/ZnS core/shell nanocrystals : controlled synthesis and photophysical properties |
| title_full | Cd-free Cu-doped ZnInS/ZnS core/shell nanocrystals : controlled synthesis and photophysical properties |
| title_fullStr | Cd-free Cu-doped ZnInS/ZnS core/shell nanocrystals : controlled synthesis and photophysical properties |
| title_full_unstemmed | Cd-free Cu-doped ZnInS/ZnS core/shell nanocrystals : controlled synthesis and photophysical properties |
| title_short | Cd-free Cu-doped ZnInS/ZnS core/shell nanocrystals : controlled synthesis and photophysical properties |
| title_sort | cd free cu doped znins zns core shell nanocrystals controlled synthesis and photophysical properties |
| topic | Cadmium Free Colloidal Quantum Dots |
| url | https://hdl.handle.net/10356/86304 http://hdl.handle.net/10220/45237 |
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