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Abstract Localized surface plasmon resonance (LSPR) is shown to be effective in trapping light for enhanced light absorption and hence performance in photonic and optoelectronic devices. Implementation of LSPR in all‐inorganic perovskite nanocrystals (PNCs) is particularly important considering their unique advantages in optoelectronics. Motivated by this, the first success in colloidal synthesis of AuCu/CsPbCl3core/shell PNCs and observation of enhanced light absorption by the perovskite CsPbCl3shell of thickness in the range of 2–4 nm, enabled by the LSPR AuCu core of an average diameter of 7.1 nm, is reported. This enhanced light absorption leads to a remarkably enhanced photoresponse in PNCs/graphene nanohybrid photodetectors using the AuCu/CsPbCl3core/shell PNCs, by more than 30 times as compared to the counterparts with CsPbCl3PNCs only (8–12 nm in dimension). This result illustrates the feasibility in implementation of LSPR light trapping directly in core/shell PNCs for high‐performance optoelectronics.
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Dual‐Protected Metal Halide Perovskite Nanosheets with an Enhanced Set of Stabilities
Abstract Approaches to achieve stable perovskite nanocrystals (PNCs) of interest, in particular those with large structural anisotropy, through protective coating of the inorganic shell at a single‐nanocrystal (NC) level are comparatively few and limited in scope. Reported here is a robust amphiphilic‐diblock‐copolymer‐enabled strategy for crafting highly‐stableanisotropicCsPbBr3nanosheets (NSs) by in situ formation of a uniform inorganic shell (1st shielding) that is intimately ligated with hydrophobic polymers (2nd shielding). The dual‐protected NSs display an array of remarkable stabilities (i.e., thermal, photostability, moisture, polar solvent, aliphatic amine, etc.) and find application in white‐light‐emitting diodes. In principle, by anchoring other multidentate amphiphilic polymer ligands on the surface of PNCs, followed by templated‐growth of shell materials of interest, a rich variety of dual‐shelled, multifunctional PNCs with markedly improved stabilities can be created for use in optics, optoelectronics, and sensory devices.
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- PAR ID:
- 10221818
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 60
- Issue:
- 13
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 7259-7266
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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