Photoluminescence study of up-conversion phosphor La₂(MoO₄)₃ Yb³⁺, Er³⁺ prepared by precipitation method

Up-conversion phosphors of La₂(MoO₄)₃: Yb³⁺, Er³⁺ with different concentration of Erbium were prepared by a simple precipitation method. The crystal structure, surface morphology, elemental composition and photoluminescence properties were characterized by X–ray powder diffraction (XRD), Scanning electron microscopy (SEM), Energy dispersive X–ray Spectroscopy (EDAX) and Photoluminescence spectroscopy respectively. XRD spectra show high degree of crystallinity in all samples. SEM images shows rod like structures presence in the samples. EDAX analysis confirm the presence of dopants (Yb³⁺ and Er³⁺) in the host matrix (La₂(MoO₄)₃). Upon excitation by 980 nm infrared radiation, all the samples give emission peaks between 524 – 533 nm in the bluish green region, 546 – 555 nm in the green region and 659 – 672 nm in the red region which are attributed to the ²H_11/2 → ⁴I_15/2, ⁴S_3/2 → ⁴I_15/2 and ⁴F_9/2 → ⁴I_15/2 transitions of Er³⁺ ions respectively. (author)