Ln3+ (Ln Eu, Dy, Sm, and Er) Ion-Doped YVO4 Nano/Microcrystals with Multiform Morphologies: Hydrothermal Synthesis, Growing Mechanism, and Luminescent Properties

YVO4 nano/microcrystals with multiform morphologies, such as nanoparticles, microdoughnut, micropancake, pillar structure, and microflower, have been synthesized via a facile hydrothermal route. A series of controlled experiments indicate that the shape and size of as-prepared architectures can be tuned effectively by controlling the reaction conditions, such as reaction time, vanadium sources, different organic additives, and the molar ratio of organic additive trisodium citrate (Cit(3-)):Y3+. It is found that Cit(3-) as a ligand and shape modifier has the dynamic effect by adjusting the growth rate of different facets under different experimental conditions, resulting in the formation of various geometries of the final products. The possible formation mechanisms for products with diverse architectures have been presented in detail. Additionally, we systematically investigate the luminescent properties of the YVO4:Ln(3+) (Ln = Eu, Dy, Sm, and Er). Because of an efficient energy transfer from vanadate groups to dopants, YVO4:Ln(3+) (Ln = Eu, Dy, Sm, and Er) phosphors showed their strong characteristic emission under ultraviolet excitation and low-voltage electron beam excitation. The ability to generate YVO4 nano/microstructures with diverse shapes, multicolor emission, and higher quantum efficiency provides a great opportunity for systematically evaluating their luminescence properties, as well as fully exploring their applications in many types of color display fields.