Finding a novel Ca2M3(SiO4)2(PO4)O (M = La, Y):Eu3+ red-emitting phosphor with positive responsiveness to phytochrome: Application in plant cultivation

A series of far-red-emitting Ca2M3(SiO4)(2)(PO4)O (M = La, Y) (CMSPO):xEu(3+) (x = 0.05, 0.10, 0.20, 0.30, 0.40 and 0.50) phosphors were successfully synthesized by high-temperature solid-phase reaction. The fabricated samples were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), fourier transform infrared (FT-IR), ultraviolet-visible diffuse reflectance (UV-Vis DR), photoluminescence excitation (PLE) and emission (PL) spectra. Under 394 nm excitation, the samples show red emission locating at 618 nm, which is attributed to the D-5(0) -> F-7(2) electric dipole (ED) transition. Also, a deep red-emitting originating from D-5(0) -> F-7(4) transition matches well with the absorption spectra of P-R and P-FR regions. It is also found that the PL intensity of CLSPO:0.30Eu(3+) is enhanced about 1.6 times compared with the CYSPO:0.20Eu(3+). Additionally, the results demonstrated that the phosphors can provide reference for the development of Eu3+-doped phosphors that can be used for plant cultivation LEDs.