In the core–crown structure, the CdSe and CdS modes preserve more independent behaviour with only interface modes forming the phonon overtones with phonons of the core. The core and the shell are typically composed of type IIVI, IVVI, and IIIV semiconductors, with configurations such as CdS/ZnS, CdSe/ZnS, CdSe/CdS, and InAs/CdSe (typical notation is: core/shell) 2 Organically passivated quantum dots have low fluorescence quantum yield due to surface related trap states. This behaviour is explained by strong mutual influence of the core and shell and formation of combined phonon modes. The general difference is the larger number of phonon modes in core/shell NPLs and their spectral shifts with increasing shell thickness, as well as with E exc. A number of distinct spectral features of the two NPL morphologies are observed, which are further modified by tuning the laser excitation energy E exc between in- and off-resonant conditions. However, since CdSe and CdS have the same crystal structure, same cations, and similar lattice parameters, it is very challenging to image the interface. Here, we investigated by Raman and infrared spectroscopy the phonon spectra and electron–phonon coupling in CdSe/CdS core/shell and core–crown NPLs. CdSeCdS Coreshell quantum dots (QDs) have been widely studied in recent years, due to their architecture which allows to tailor properties by controlling structure and composition. Both kinds of heterogeneous NPLs find efficient applications and represent interesting materials to study the electronic and lattice excitations and interaction between them under strong one-directional confinement. Growing CdSe and CdS parts subsequently in either side-by-side or stacked manner results in core–crown or core/shell structures, respectively. stabilized with octadecylamine ligands, fluorescence em 645 nm, solid. In this work, CdS and ZnS shells with different shell thickness are grown on 2. CdSe/ZnS core-shell type quantum dots 900212. Overall, present findings demonstrate unique advantages of the nanoshell QD architecture as a promising optical gain medium in solid-state lighting and lasing applications.Recently developed two-dimensional colloidal semiconductor nanocrystals, or nanoplatelets (NPLs), extend the palette of solution-processable free-standing 2D nanomaterials of high performance. While an inorganic shell can enhance the photoluminescence quantum yields (PLQYs), the role of the shell with respect to TET is still not clear. An extensive charge delocalization in nanoshell QDs was confirmed by transient absorption measurements, showing that the presence of a bulk-size core in CdS bulk/CdSe/CdS shell QDs reduces exciton–exciton interactions. A unique combination of a large exciton volume and a smoothed potential gradient across interfaces of the reported CdS bulk/CdSe/CdS shell (core/shell/shell) nanoshell QDs results in strong suppression of Auger processes, which was manifested in this work though the observation of stable amplified stimulated emission (ASE) at low pump fluences. Here, we report on a two-dimensional nanoshell quantum dot (QD) morphology that enables a strong delocalization of photoinduced charges, leading to enhanced biexciton lifetimes and low lasing thresholds. This usually requires the employment of charge-delocalizing particle architectures, such as core/shell NCs, nanorods, and nanoplatelets. CdSe/CdS, core/shell structure has been synthesized from Cadmium oxide, Sulphur, Trioctylphosphine, Trioctylphosphineoxide, Octadecene, stearic acid and. Currently, one of the key challenges facing the development of high-performance NC optical gain media lies in enhancing the lifetime of biexciton populations. Colloidal semiconductor nanocrystals (NCs) represent a promising class of nanomaterials for lasing applications. Se K-edge XAS was collected from the CdSe rods at Advanced Light Source beamline 10.3.2 (Berkeley, CA), using a 16 m (horizontal) × 7 m (vertical) m beam spot.5 This small spot size allowed us to collect data from a single domain of oriented nanorods.
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