Toward white light emission from plasmonic-luminescent hybrid nanostructures

Abstract

We study the light emission of plasmonic-luminescent hybrid nanostructures consisting of Ag nanoparticles (NPs) embedded in europium oxide (EuOX). The Ag NPs present a bidimensional organization in the nanostructures and they optically behave as oblate spheroids. The photoluminescence (PL) spectral response of the nanostructures evolves from a narrow red emission characteristic of Eu3+ ions in absence of Ag NPs to a broad blue-green emission band associated with Eu2+ ions when the layer of Ag NPs is present. This behavior is not related to a change in the Eu2+/Eu3+ ratio, which is verified by compositional analysis. Instead, a detailed investigation of the PL emission of the nanostructures suggests that the coupling of the Ag NPs to the Eu2+ ions present in the EuOX layer, which manifests itself in an efficient sensitization of these ions, enhances their broad visible emission. In particular, the longitudinal mode of the Ag NPs surface plasmon is considered to be responsible for the efficient energy transfer for the non-normal incidence excitation PL configuration used. Finally, the use of a capping amorphous Al2O3 layer allows improving the robustness of hybrid nanostructures and further enhances their PL emission. These findings provide a new path to actively control the selective excitation of Eu2+ and Eu3+ ions via a controlled coupling with the surface plasmon resonance modes of the Ag NPs and points to these nanostructures as promising building blocks for the development of integrable white light sources.

Hierarchical Carbon Nanocone-Silica Metamaterials: Implications for White Light Photoluminescence

“…Using the results shown in Figure for samples 02A and 03A which are characterized by the presence of nanocones and broad emission peaks, we obtain a spectral temperature of approximately T SPEC ≃ 6080 K which is near the optimum value for the white light emission. Importantly, this value which is a full width at half-maximum of our spectra is quite comparable to the most recent characteristics of white light emitters based on luminescent hybrid nanostructures containing europium and single emissive layer perovskites . Moreover, our spectra have a much larger blue component in the spectrum, which is missing in the present devices.…”

“…Importantly, this value which is a full width at half-maximum of our spectra is quite comparable to the most recent characteristics of white light emitters based on luminescent hybrid nanostructures containing europium and single emissive layer perovskites. 29 Moreover, our spectra have a much larger On the basis of these measurements, we conclude that our carbon nanocones metamaterials are very promising candidates as white light emitters for building WLED devices.…”

“…The manufacturing processes for these materials are often complicated due to the need for a fine-tuning and control of the nanoparticles size, 27 matrix composition, and substrate, 29 often using rare materials, as well as of the reproducibility of the expected optical characteristics. To overcome these difficulties, much research still needs to be done in order to develop suitable and sustainable materials, as well as new tools for the analysis of correlations between the material response and its morphological characteristics.…”

“…As a fundamental requisite, WLEs need to possess a wide and robust photoluminescent spectrum in the visible range to be considered as good WLE candidates. The growing need for sustainable lighting technologies has recently led to the search for new photoluminescent materials such as perovskites-based ones, colloidal quantum dots, luminescent hybrid nanostructures, carbon quantum dots, , and so forth.…”

Doping Concentration Regulates the Optical and Magnetic Properties of Twinned Crystal Cu2–xEuxO

“…%) (Figure S4). The Eu 3d region presents characteristic peaks at 1135.4 and 1164.8 eV, attributable to Eu 3+ 3d 5/2 and Eu 3d 3/2 , respectively, demonstrating a 29.4 eV splitting of the Eu 3d doublets and confirming a singular valence state of +3 for the Eu element at the surface (Figure g). − Figure h presents a high-resolution XPS spectrum, where the O 1s peaks are discernible and can be bifurcated into two components at 531.7 and 530.2 eV. The peak at 531.7 eV is linked to the lattice oxygen (O 2– ), while the 530.2 eV peak is attributable to surface-absorbed O or H 2 O and oxygen (O 2– ) in oxygen-deficient regions. , In Figure S4, the peaks that appear between 932 and 953 eV are identified as Cu 2p XPS peaks.…”