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In this study, [Formula: see text]-doped yttrium oxide nanophosphors were prepared using the hydrothermal method assisting with the polyacrylic acid (PAA), phenol formaldehyde resin precursor (PF), and gum arabic (GA), respectively and their structural and optical properties were studied. X-ray diffraction (XRD) patterns of the samples can be well indexed to the cubic structure. Additionally, scanning electron microscopy (SEM) images showed that the samples were different morphologies, via combining with different templates. The luminescence results revealed that the addition of templates have a significant influence on the luminescence properties of [Formula: see text]-doped [Formula: see text].

A series of enhanced red and green emission phosphors: [Formula: see text] (SYP): [Formula: see text], [Formula: see text] were successfully synthesized via a novel hydrothermal method. The structural and optical properties were investigated through XRD and PL (photoluminescence) measurements. The results of PL spectra revealed that SYP exhibited red and green emission for [Formula: see text], [Formula: see text]-phosphors doped, respectively. In order to obtain optimal phosphors, we proposed the concentration of dopants and the reaction time. Results indicated that enhanced red and green emission phosphors SYP may be potential candidates in light-emitting diodes (LEDs).

Barium molybdate (BMO) powders doped with Re[Formula: see text] (Eu, Sm, Tb, Dy) were successfully synthesized by the solid-state reaction with the assistance of polyvinyl alcohol (PVA). The effects of the reaction conditions and activator ions on the structural and luminescence properties of BMO were extensively investigated. The results of powder X-ray diffraction (XRD) and Raman spectra exhibited the structures of the phosphors, which demonstrate that the Eu[Formula: see text] have been effectively doped into the BaMoO4 (BMO) lattice. The factors of PVA amount, Eu[Formula: see text]-doped concentration and different dopants on phosphor samples were investigated via photoluminescence (PL) measurements. The as-synthesized samples degrade as a two-step degradation by thermogravimetric analysis. BMO phosphors show strong multicolor emission with different dopant RE[Formula: see text] ions: red–orange (Eu[Formula: see text]), red (Sm[Formula: see text]), green (Tb[Formula: see text]) and green–yellow (Dy[Formula: see text]) under ultraviolet excitation, which may find potential applications in light phosphor powders, light-emitting diodes (LEDs) and device in photochemical field.

Red phosphors of Eu[Formula: see text]-doped bismuth molybdate (BMO) are prepared by a low temperature hydrothermal method assisting with Phenol Formaldehyde resin (PFr), and characterized by X-ray diffraction (XRD) patterns, Fourier transform infrared-spectroscopy (FT-IR), thermogravimetric analyzer (TGA), differential thermal analyzer (DTA), and photoluminescence (PL) spectroscopy. PL properties influence factors including molar ratio of Bi[Formula: see text] and Mo[Formula: see text] ions, PFr dosage and dopants concentration are discussed in detail. The results show that BMO can act as a useful host for Eu[Formula: see text] ions doping, and energy transferring from Bi[Formula: see text] to Eu[Formula: see text] achieved efficiently, the BMO phosphors displayed intense red color emission under ultraviolet light excitation.

A method for mixed-phase bismuth molybdate doped with Eu[Formula: see text] ions was developed by solid-state reaction assisting with polyvinyl alcohol (PVA). The results of powder X-ray diffraction showed a mixed-phase structure and the microscopical characterization technology revealed the formation process with the addition of PVA. As a structure inducer, the PVA molecules played a vital role in the formation of phase structure. The as-obtained Eu[Formula: see text]-doped bismuth molybdates were also characterized by using different spectroscopic techniques including FTIR and photoluminescence (PL). The results show that doping concentration, PVA addition and calcination temperature affect photoluminescence properties remarkably.

Scheelite (CaWO4)-type microphosphors were synthesized by the precipitation method assisted with cetyltrimethyl ammonium bromide (CTAB). All compounds crystallized in the tetragonal structure with space group [Formula: see text] (No. 88). FE-SEM micrographs illustrate the spherical-like morphologies and rough surface. PL spectra indicate the broad emission peak maximum at 613 nm under UV excitation. Luminescence decay curves monitored by [Formula: see text] transition ([Formula: see text] nm) of Eu[Formula: see text] in doped CaWO4 are presented, the curves exhibit a single-exponential feature and the lifetime for doped CaWO4 is 0.61 ms.

CaWO4 crystals were prepared by hydrothermal method assisting with phenol-formaldehyde polymer. The morphology can be controlled by polymer, and X-ray diffraction patterns results present a scheelite-type tetragonal structure, characteristic infrared active modes for O–W–O in the range from 500 cm[Formula: see text] to 4000 cm[Formula: see text] by Fourier transform infrared spectroscopic techniques. Raman results indicate that the crystals possess seven Raman active modes in the range from 100 cm[Formula: see text] to 1000 cm[Formula: see text]. A scanning electron microscopy study reveals that the particles exhibit uniform morphology. Luminescent properties were investigated by photoluminescence measurements, multicolor phosphors were obtained when Ca[Formula: see text] was substituted partly by lanthanide ions.