Microwave-assisted hydrothermal synthesis of novel series Ce1.8A0.2(MoO4)3 (A = Ag+, Zn+2, Y+3, Ti+4, Nb+5): influence of dopant on structural and photoluminescent properties and possible application for pc-WLEDs

Molybdate-based materials, especially those with the formula RE 2 (MoO 4 ) 3 (RE = rare earths), have been widely investigated in recent years. However, cerium molybdate (Ce 2 (MoO 4 ) 3 ) is still underexplored. Thus, this work aimed to synthesize and study pure and transition-ion-doped Ce 2 (MoO 4 ) 3 , in order to evaluate the influence of the dopants on the physical and optical properties of the materials. The compounds Ce 1.8 A 0.2 (MoO 4 ) 3 (A = Ag + , Zn +2 , Y +3 , Ti +4 , Nb +5 ) were synthesized by a microwave-assisted hydrothermal method and characterized by X-ray diffraction (XRD), scanning electron microscopy (FE-SEM), UV-Vis spectroscopy, and photoluminescence (PL). The results confirmed the formation of the pure tetragonal phase, without secondary phases. Morphological analyses indicated dopant-dependent variations, with the formation of nanoplates and oval structures. The doped materials showed variations in the band gap, associated with the creation of intermediate levels in the structure. Photoluminescence spectra revealed a reduction in intensity and broadening of emission in the visible spectrum, indicating less electron-hole pair recombination. Some samples showed properties suitable for emitting cool white light, with high chromatic quality. Among them, Ce 1.8 Zn 0.2 (MoO 4 ) 3 stood out, being successfully used in the fabrication of a white LED prototype.