Color-tunable luminescence for Bi3+/Ln3+:YVO4 (Ln = Eu, Sm, Dy, Ho) nanophosphors excitable by near-ultraviolet light

Abstract

Bi³⁺/Ln³⁺:YVO₄ nanocrystals with a mean size of 6 nm are prepared through a mixed solvothermal route. With Bi³⁺ doping, the excitation band corresponding to the Ln³⁺ emission is shifted from 280 nm to 345 nm, owing to the occurrence of Bi³⁺ → V⁵⁺ metal–metal charge transfer and the subsequent energy transfer to Ln³⁺ ions. Under near-ultraviolet excitation, the emission color of Bi³⁺/Ln³⁺:YVO₄ nanophosphors can be easily tuned by changing the Ln³⁺ ions.