NaYF4:Pr³⁺nanocrystals displaying photon cascade emission

Abstract

The quantum-cutting process is observed in nanocrystalline fluoride (NaYF(4)) doped with Pr(3+). The thermal decomposition synthesis method was used to synthesize the NaYF(4) nanocrystals with an average size of 42 nm. The morphological high resolution transmission electron microscopy (HRTEM), structural X-ray diffraction (XRD) and spectroscopy, with the use of synchrotron radiation, have been employed to characterize the material. The different excitation energies created different luminescence response of the NaYF(4):Pr(3+) nanocrystals. The quantum-cutting phenomenon has been observed under the direct excitation of the 4f5d bands of praseodymium. After excitation of the NaYF(4) matrix this process is quenched and part of the energy is released through the self-trapped excitons emission. The origin of the different types of emission transitions has been analyzed in detail.

Synthesis of β-Phase NaYF4:Yb,Er Upconversion Nanocrystals and Nanorods by Hot-Injection of Small Particles of the α-Phase

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Concentration quenching, surface and spectral analyses of SrF2:Pr3+ prepared by different synthesis techniques

“…Pr 3+ doped materials have been extensively investigated due to its potential use in a variety of applications [1][2][3][4][5]. For phosphor applications, the 4f-4f transitions are the most relevant, especially the 1 D 2 ?…”

Enhanced luminous efficiency in Pr3+ activated Ca0.5La(MoO4)2 red phosphor with blue excitation for WLED applications

“…Because, Pr 3? activated materials have engrossed much attention and used in several potential applications, such as fiber optical communications, UV and visible lasers, upconversion lasers, optoelectronic devices, field emission display devices, lamp phosphors and improving solar cell efficiency [11][12][13][14][15][16]. Pr 3?…”