Fabrication and Upconversion Photoluminescence of CaMoO4: Er3+, Yb3+ Particles by A Cyclic Microwave-Assisted Metathetic Method

Abstract

Well-crystallized Er³⁺/Yb³⁺ co-doped CaMoO₄ (CaMoO₄:Er³⁺/Yb³⁺) particles were successfully synthesized via a cyclic microwave-assisted metathetic method, followed by further heat-treatment at 600 ºC for 3 h, showing a fine and homogeneous morphology with sizes of 0.2-1 μm. With excitation at 980 nm, CaMoO₄:Er³⁺/Yb³⁺# exhibited a strong 525-nm emission band and a weak 550-nm emission band in the green region and a weak 655-nm emission band in the red region. The Raman spectra of CaMoO₄:Er³⁺, CaMoO₄:Er³⁺/Yb³⁺, CaMoO₄:Er³⁺/Yb³⁺# and CaMoO₄:Er³⁺/Yb³⁺## particles indicated that the additional strong peaks at higher frequencies (618, 575, 492, 420 and 373 cm^-1) and at lower frequencies (290 and 234 cm^-1).