Upconversion Photoluminescence Properties of PbY2 (MoO4) (4):Er3+/Yb3+ Phosphors Synthesized by Microwave Sol-Gel Method

摘要

PbY2- (x) (MoO4)(4):Er3+/Yb3+ phosphors with the correct doping concentrations of Er3+ and Yb3+ (x = Er3+ + Yb3+, Er3+ = 0.05, 0.1, 0.2, and Yb3+ = 0.2, 0.45) were successfully synthesized using the microwave sol-gel method; their upconversion photoluminescence properties were investigated in detail. Well-crystallized particles, formed after heat-treatment at 900 degrees C for 16 h, showed a fine and homogeneous morphology with particle sizes of 2-5 mu m. Under excitation at 980 nm, the PbY (1.7)(MoO4)(4):Er0.1Yb0.2 and PbY1.5(MoO4)(4):Er-0.05 Yb-0.45 particles exhibited a strong 525-nm emission band, a weak 550-nm emission band in the green region, and a very weak 655-nm emission band in the red region. The Raman spectra of the doped particles indicated the presence of strong peaks at higher and lower frequencies induced by disordered structures of PbY2-x(MoO4)(4) by the incorporation of the Er3+ and Yb3+ ions into the crystal lattice, which resulted in the unit cell shrinkage accompanying the new phase formation of the MoO4-x group.