Enhanced red luminescence in CaAl12O19:Mn4+ via doping Ga3+ for plant growth lighting
A series of solid solution CaAl12-xGaxO19:Mn4+ phosphors were prepared via high temperature solid state reaction. The structural properties were characterized by X-ray diffraction (XRD) and the luminescence was investigated through photoluminescence spectra. The obtained CaAl12-xGaxO19:Mn4+ phosphor has a strong broad excitation band in the range of 250-550 nm which can be easily excited by UV, NUV and blue light, and a broad emission band centered at 655 nm between 600 nm to 800 nm due to the 2E→4A2 transition of Mn4+ ion. PL spectra indicated that the intensity of CaAl12O19:Mn4+ can be enhanced when the value of Ga3+concentration equal to 1. Furthermore, the element mapping, optical properties, thermal stability, fluorescence lifetime and CIE chromaticity revealed that the CaAl12-xGaxO19:Mn4+ phosphors can be considered as a potential candidate in indoor plant cultivation.