Abstract
CdSe/CdS with ZnS/ZnO shell quantum dots (QDs) are synthesized by a one-pot method with various oleylamine (OLA) contents. The crystal structures of the QDs were analyzed by X-ray diffractometry, which showed ZnS diffraction peaks. It was represented that the ZnS shell was formed on the surface of the CdSe/CdS core. Interestingly, QDs with a high OLA concentration exhibit diffraction peaks of ZnS/ZnO. As a result, the thermal stability of QDs with ZnS/ZnO shells exhibits better performance than those with ZnS shells. In addition, the photoluminescence intensity of QDs with ZnS/ZnO shells shows a relatively slow decay of 7.1% compared with ZnS shells at 85 °C/85% relative humidity aging test for 500 h. These indicate that QDs with different OLA modifications can form ZnS/ZnO shells and have good stability in a harsh environment. The emission wavelength of QDs can be tuned from 505 to 610 nm, suitable for micro-LED display applications.
Highlights
Nanomaterials 2022, 12, 909. https://For nearly 2 decades, quantum dots (QDs) have attracted attention and are widely used in sensors, detectors, and solar cells [1–3]; they exhibit a broad application prospect in the field of analysis and detection because the quantum confinement effects are accompanied by tunable and excellent fluorescence characteristics such as high fluorescence quantum yield, stable luminescence, wide excitation spectrum, and narrow emission spectrum [4,5].the luminous efficiency of QDs degrades in a harsh environment, including water, thermal heating, and ultraviolet (UV) exposure [6], because of the uneven surface or lack of surfactant of QDs
The different sizes of CdSe/CdS with ZnS or Zinc oxide (ZnO) shell QDs are prepared by one-pot synthesis with different OLA contents
We illustrated that the CdSe/CdS/ZnS core–shell QDs with emission wavelengths from 505 to 610 nm can be realized for the first time using a simple one-pot synthesis in the presence of OLA contents
Summary
Nanomaterials 2022, 12, 909. https://For nearly 2 decades, quantum dots (QDs) have attracted attention and are widely used in sensors, detectors, and solar cells [1–3]; they exhibit a broad application prospect in the field of analysis and detection because the quantum confinement effects are accompanied by tunable and excellent fluorescence characteristics such as high fluorescence quantum yield, stable luminescence, wide excitation spectrum, and narrow emission spectrum [4,5].the luminous efficiency of QDs degrades in a harsh environment, including water, thermal heating, and ultraviolet (UV) exposure [6], because of the uneven surface or lack of surfactant of QDs. This concept can effectively improve separation efficiency and suppress charge recombination These materials of heterojunction in QDs are divided into two types. An electron can be excited from the valance to the conduction band and will be confined to the inner material. In type II, the core’s conduction band is higher than that of the shell, where an electron will excite from the core’s valance band to the shell’s conduction band [10,11]. To develop high quality and high stability QDs, the type I core–shell structure of CdSe/CdS@ZnS or Zinc oxide (ZnO) QDs has been adopted in various studies, such as light-emitting diodes and biomedical applications.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
