Investigation of the luminescent properties of Sm3+ ion-doped BiVO4 synthesized via the hydrothermal method

Abstract

BiVO₄ phosphors doped with different concentrations of Sm³⁺ ions (1, 3, 5, and 7 mol%) were prepared by the hydrothermal synthesis method and heat-treated at 160 °C for 12 h. X-ray diffraction results show that when Sm³⁺ ions replace Bi³⁺ ions at lattice sites, no second phase is formed in BiVO₄ as the Sm³⁺ doping concentration increases, and the monoclinic crystal structure is maintained. With increasing Sm³⁺ doping concentration, the phosphor powders exhibit irregular particle morphology, and the particle sizes are non-uniform. Regarding the photoluminescence properties, the emission spectra are mainly composed of the characteristic emission peaks of Sm³⁺ ions, corresponding to the electronic transitions at 566 nm (⁴G_5/2 → ⁶H_5/2), 605 nm (⁴G_5/2 → ⁶H_7/2), and 648 nm (⁴F_9/2 → ⁶H_9/2). As the Sm³⁺ concentration increases, the emission intensity of the 604 nm peak (⁴G_5/2 → ⁶H_7/2) first increases and then decreases. When the Sm³⁺ doping concentration is 3 mol%, the phosphor exhibits the optimal emission intensity with CIE chromaticity coordinates are (x = 0.301, y = 0.374), which are located in the near-white light region.