Luminescence properties of Y5Si3O12N:Ce3+/Tb3+ co-doped oxynitride phosphors

As possible alternative applying to trichromatic white LEDs, oxynitirde phosphors which are consist of a range of Y-Si-ON: single doped Ce³⁺ and Y-Si-ON: Ce³⁺\Tb³⁺ co-doping were smoothly prepared with the use of typical solid state reaction route. Not only the purity of the resulting phosphors was raised, but also the intensity of emission was enhanced due to the introduction of Li₂CO₃ flux (5wt %). A strong wide excitation band is suitable for UV LED chips that is ranging from 200 nm to 400 nm having maximum peak around 358 nm has been noticed. In the Ce³⁺ mono-doped phosphor, we noted a strong blue emission whose peak is at 439 nm at this excitation wavelength and in the Y₅Si₃O₁₂N:Ce³⁺/Tb³⁺ co-doped phosphors two different light bands were also noted: the blue band was at 439 nm when reached its peak due to the Ce³⁺ ion and because of the and a highly efficient green emission of having maximum peak around 549 nm as a result of Tb3+ ions transitions (⁵D₄→⁷F₅).