Low temperature microwave solid-state synthesis of red-emitting CaMoO4:Eu3+, Li+ phosphors with controlled morphology

Abstract

CaMoO₄:Eu³⁺, Li⁺ red phosphors have been successfully achieved by a microwave-assisted solid-state reaction, and their morphologies and luminescence properties have been studied in this paper. The as-prepared Ca_0.9MoO₄:0.05Eu³⁺, 0.05Li⁺ powders occur as uniform spherical particles with a size distribution of 1–2 μm via the optimized reaction temperature at 600 °C and reaction time of 1 h. The phosphors showed an intense red emission with maxima at 615 nm, which was ascribed to the Eu³⁺ electric dipole transition of ⁵D₀ → ⁷F₂. The comparison on the morphology and luminescence property between the as-prepared samples and the samples obtained by the conventional method was discussed in detail. A possible microwave-assisted solid-state reaction mechanism was proposed, and the effect of the microwave sintering temperature and time was also discussed.