Doping of CsPbBr3perovskite nanocrystals (PNCs) to achieve excellent material properties is accelerating due to their increasing use in optoelectronic devices. Herein, a novel composite of CsPbBr3PNCs with nickel thiocyanate Ni(SCN)2is reported, exhibiting stronger photoluminescence (PL) and more extended stability. The addition of Ni(SCN)2at different molar concentrations reduces the surface trap states of the host PNCs. Therefore, the microstrain, dislocation density, PL emission linewidth, and Urbach energy decrease, resulting in an increased photoluminescence quantum yield (PLQY) from 72% to high above 90%. When stored in the ambient atmosphere for 120 days, the PLQY of doped PNCs is maintained by more than four times compared to host PNCs. A combination of 3D‐printed conversion layers containing green‐, yellow‐, and red‐emitting doped PNCs with blue light‐emitting diodes results in stable white light with superior color qualities. Hence, new composites with desired properties are developed as an alternative to conventional color phosphors.
This content will become publicly available on November 1, 2024
As a class of semiconductor nanocrystals that exhibit high photoluminescence quantum yield (PLQY) at tunable wavelengths, perovskite nanocrystals (PNCs) are attractive candidates for optoelectronic and light‐emitting devices. However, attempts to optimize PNC integration into such applications suffer from PNC instability and loss of PL over time. Here, we describe the impact of organic and polymeric N‐oxides when used in conjunction with PNCs, whereby a significant increase in PNC quantum yield is observed in solution, and stable PL emission is obtained in polymeric nanocomposites. Specifically, when using aliphatic N‐oxides in ligand exchange with CsPbBr3PNCs in solution, a substantial boost in PNC brightness is observed (~40% or more PLQY increase), followed by an alteration of the perovskite chemistry. When N‐oxide substituents are positioned pendent to a poly(n‐butyl methacrylate) backbone, the optically clear flexible nanocomposite films obtained have bright PL emission and maintain optical clarity for months. X‐ray diffraction is useful for characterizing the PNC crystalline structure following exposure to aliphatic N‐oxides, while electron microscopy (EM) and small‐angle X‐ray scattering (SAXS) measurements of the PNC‐polymer nanocomposites show this polymeric N‐oxide platform to cleanly disperse PNCs in flexible polymer films.
more » « less- NSF-PAR ID:
- 10472179
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Polymer Science
- ISSN:
- 2642-4150
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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