摘要

Tetragonal t-LaVO4:Ln(3+) (Ln(3+) = Eu3+, Dy3+, Sm3+) microrod array and 3D hierarchical nanostructures with sheaf-like, flower-like, cauliflower-like, and spherical morphologies have been successfully synthesized on glass substrate through a simple hydrothermal process assisted by ethylenediaminetetraacetic acid disodium salt (Na2H2L). The morphologies of the products varied dramatically when Na2H2L/La3+ molar ratio and reaction time were changed in system. A possible crystal growth mechanism is proposed for the self-assembly of nanorods into the observed microstructures based on detailed experiments. Due to an efficient energy transfer from VO4 (3-) to the Ln(3+) dopants, the self-assembled t-LaVO4:Ln(3+) (Ln(3+) = Eu3+, Dy3+, Sm3+) superstructures showed strong characteristic dominant emissions of the Eu3+, Dy3+, Sm3+ ions at 616 nm (D-5(0) -> F-7(2), strong red), 573 nm (F-4(9/2) -> H-6(13/2), yellow), 603 nm ((4)G(5/2) -> H-6(7/2), orange-red) under ultraviolet excitation, respectively. This work not only gives insight into understanding the hierarchical growth behaviour of t-LaVO4:Ln(3+) nanoarchitectures in a solution-phase system, but also provides a potential route to building other superstructures assembled from one-dimensional nanoparticles.