Submicrometre‐sized EuPO ₄ hollow spheres: template‐directed synthesis and luminescent properties

Abstract

Submicrometre-sized EuPO 4 hollow spheres were synthesised by utilising the colloidal spheres of Eu(OH)CO 3 as the sacrificial template, for the first time. The EuPO 4 hollow spheres were investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and photoluminescence, respectively. The EuPO 4 hollow spheres exhibit red colour emission from 5 D 0-7 F J (J = 1, 2, 3, 4) transitions of the Eu 3+ ions. The obtained EuPO 4 hollow spheres may have potential applications in cell biology, drug release, diagnosis, due to the high chemistry stability and luminescence function.

Extensive tailoring of REPO4 and REVO4 crystallites via solution processing and luminescence

“…24,103,104 Quantum yield (QY) is an important parameter to qualify a phosphor, though it is much less reported than the spectral features of luminescence. Nevertheless, the QYs of EuPO 4 hollow spheres, 7 GdPO 4 :Eu 3+ nanoneedles, 105 h-LaPO 4 :Eu 3+ nanorods 106 and m-LaPO 4 :Eu 3+ nanoparticles 106 were reported to be ∼16.6%, 19%, 58.5% and 28.7%, respectively.…”

“…78,79 Zhang et al obtained submicron-sized h-EuPO 4 hollow spheres via hydrothermally reacting Eu(OH)CO 3 colloid spheres (sacrificial template) with PO 4 3− and demonstrated their potential in biological applications. 7 Tian et al , on the other hand, fabricated well-defined GdPO 4 hollow spheres of hierarchical microstructure by combining homogeneous precipitation and hydrothermal reaction with 3-aminophenol-formaldehyde resin spheres as a self-sacrificial template, and demonstrated their favorable biocompatibility and drug delivery capacity and their potential application in optical/magnetic dual imaging upon Eu 3+ and Tb 3+ doping. 80 Self-assembled 2D and 3D particles/microstructures are drawing attention for applications in photodetectors, photodiodes, catalysis, energy conversion and biological science.…”

“…24,103,104 Quantum yield (QY) is an important parameter to qualify a phosphor, though it is much less reported than the spectral features of luminescence. Nevertheless, the QYs of EuPO 4 hollow spheres, 7 GdPO 4 :Eu 3+ nanoneedles, 105 h-LaPO 4 :Eu 3+ nanorods 106 and m-LaPO 4 :Eu 3+ nanoparticles 106 were reported to be ∼16.6%, 19%, 58.5% and 28.7%, respectively. The t-LaVO 4 :Eu 3+ nanorods and m-LaVO 4 :Eu 3+ nanoparticles prepared by Cit 3− /EDTA-assisted hydrothermal reaction were measured to have QYs of ∼65% and 19% for their optimal Eu 3+ contents of 10 and 12 at%, respectively.…”

“…5 Rare-earth orthophosphate (REPO 4 , RE = La-Lu lanthanide, Sc, Y) is considered as a suitable host for luminescence due to its low toxicity, extremely low water solubility (K sp = 10 −25 -10 −27 ), high thermal/photochemical stability and excellent biocompatibility/biodegradability. 6,7 Furthermore, the low phonon energy of REPO 4 , because of the rigid lattice framework arising from the strong ionic nature of RE 3+ -PO 4 3− bonding, benefits down-conversion (DC) and up-conversion (UC) luminescence through minimizing nonradiative energy loss via phonon-photon interaction. REPO 4 may also accommodate more Ln 3+ activator ions (∼1.8 × 10 21 per cubic centimeter) without substantial luminescence quenching.…”