ZnO nanowires/YAG:Ce functional heterostructure coatings with tunable optical properties

Abstract

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Nanostructuration of YAG:Ce Coatings by ZnO Nanowires: A Smart Way to Enhance Light Extraction Efficiency

“…The latter did not exhibit any luminescence when excited by a 458 nm radiation, which is a characteristic wavelength of commercial blue LEDs. This is in accordance with the excitation spectra presented in our previous paper [ 31 ]. The two other coatings are characterized by quite similar spectral profiles with broad asymmetric emission bands ranging from 475 to 750 nm.…”

“…ZnO nanostructures have already been used to improve the emission efficiency or quality of GaN-based LEDs [ 26 , 27 , 28 ], but only a few reports [ 29 , 30 , 31 ] deal with their association with phosphors to yield an enhanced white light, whether in terms of light extraction or photometric parameters. Indeed, thanks to either their near-UV/blue emission or their large visible emission band, ZnO nanostructures can lead to a higher Color Rendering Index or more suitable color temperature [ 24 , 31 ].…”

“…ZnO nanostructures have already been used to improve the emission efficiency or quality of GaN-based LEDs [ 26 , 27 , 28 ], but only a few reports [ 29 , 30 , 31 ] deal with their association with phosphors to yield an enhanced white light, whether in terms of light extraction or photometric parameters. Indeed, thanks to either their near-UV/blue emission or their large visible emission band, ZnO nanostructures can lead to a higher Color Rendering Index or more suitable color temperature [ 24 , 31 ]. In a very recent work [ 32 ], ZnO nanorods were decorated with perovskite quantum dots to produce a stable and color-tunable white emission, using a technical approach similar to the one we carried out in our previous study [ 31 ] to associate YAG:Ce nanoparticles with ZnO NW arrays.…”

“…Indeed, thanks to either their near-UV/blue emission or their large visible emission band, ZnO nanostructures can lead to a higher Color Rendering Index or more suitable color temperature [ 24 , 31 ]. In a very recent work [ 32 ], ZnO nanorods were decorated with perovskite quantum dots to produce a stable and color-tunable white emission, using a technical approach similar to the one we carried out in our previous study [ 31 ] to associate YAG:Ce nanoparticles with ZnO NW arrays. Additionally, among the several studies existing on the combination between YAG:Ce and ZnO, most of them imply ZnO micro or nanoparticles (not NWs or nanorods) blended with YAG:Ce to elaborate nanocomposites with either improved photocatalytic activity [ 33 , 34 ] or enhanced optical properties in terms of emission intensity or photometric parameters [ 35 , 36 , 37 ].…”

Synthesis of ZnO sol–gel thin-films CMOS-Compatible

“…Among all the available metal oxide materials, zinc oxide (ZnO) is one of the important n-type inorganic semiconductor materials, considered a "material of the future" that has attracted widespread attention from the scientic community. [10][11][12][13][14][15][16] This II-VI compound semiconductor has a direct wide bandgap of 3.37 eV at room temperature and a high excitation binding energy of 60 meV, giving it unique chemical and physical properties, and great potential in important elds like optoelectronics, 17 sensors, 18 solar cells. 19 Other outstanding properties (biodegradable, non-toxic, biocompatible) and abundance in nature, mean that ZnO is considered a potential promising thin-lm exhibiting good piezoelectric properties, and strong adhesion to various substrates.…”