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):xEu3+ (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 5D0 → 7F2 electric dipole (ED) transition. Also, a deep red-emitting originating from 5D0 → 7F4 transition matches well with the absorption spectra of PR and PFR regions. It is also found that the PL intensity of CLSPO:0.30Eu3+ is enhanced about 1.6 times compared with the CYSPO:0.20Eu3+. 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.