Fabrication of Eu3+ and Sm3+ Codoped Micro/Nanosized MMoO4 (M = Ca, Ba, and Sr) via Facile Hydrothermal Method and Their Photoluminescence Properties through Energy Transfer

Abstract

Eu3+ and Sm3+ codoped micro/nanosized MMoO4 (M = Ca, Ba, Sr) phosphors with various shapes have been synthesized via a facile hydrothermal method with surfactant-free environment. The morphology of the materials was found to be manipulated by the pH value of the precursor solution. MMoO4:Eu3+, Sm3+ (M = Ca, Ba, Sr) nanoflakes, microflowers, cubes, and spheres were obtained and characterized by X-ray diffraction and field emission scanning electron microscopy. The luminescent properties of the molybdate phosphors were systematically studied. The introduction of Sm3+ into each of the red-emitting phosphors MMoO4:Eu3+ (M = Ca, Ba, Sr) can generate a strong excitation line at 405 nm, originating from the 6H5/2 → 6P5/2 transition of Sm3+, significantly extending the excitation region for matching the near-ultraviolet light-emitting diodes (∼400 nm). Energy transfer from Sm3+ to Eu3+ was observed in the whole MMoO4 systems and investigated in detail in CaMoO4 as a function of Sm3+ concentrations. A back-energy ...