Synthesis and photoluminescence properties of Eu3+-doped γ-Ca3(PO4)2

Eu3+-doped (1% and 3%) γ-Ca3(PO4)2 was synthesized by high-pressure and high-temperature experimental method and the samples were characterized by X-ray diffraction. The luminescence properties of samples were investigated by emission and excitation spectra. The excitation spectra of Eu3+-doped γ-Ca3(PO4)2 showed that samples were mainly attributed to Eu3+–O2− charge-transfer band at 270 nm, and some sharp lines were also attributed to Eu3+ f–f transitions in near-UV regions with the strongest peaks at 395 nm. Under the 395 nm excitation, the intense red emission peak at 611 nm was observed. The strongest line (395 nm) in excitation spectra of those phosphors matched well with the output wavelength of UV InGaN-based light-emitting diodes (LEDs) chip. The luminescent properties suggested that Eu3+-doped γ-Ca3(PO4)2 might be regarded as a potential red phosphor candidate for near-UV LEDs.