Hydrothermal synthesis of Yb³⁺, Tm³⁺ co-doped Gd₆MoO₁₂ and its upconversion properties

Yb³⁺, Tm³⁺ co-doped Gd₆MoO₁₂ phosphors with different morphologies are prepared by the hydrothermal method. The dendrites present different morphologies (including hexagonal prisms, spindles, and spheres) after changing the pH value and edetate disodium (EDTA) usage. It is found that each of the two factors plays a crucial role in forming different morphologies.#br#The up-conversion (UC) luminescence is studied. Under 980-nm semiconductor laser excitation, relatively strong blue emission and weak red emission are observed. Finally, the effect of pumping power on the UC luminescence properties and the level diagram mechanism of Gd₆MoO₁₂:Yb³⁺/Tm³⁺ phosphor are also discussed.