Recent studies on transparent polycrystalline phosphor ceramic plates (PCPs) show its potential application in high brightness laser lighting. Herein, we explore the luminescence properties of Ce³⁺ cation in transparent Sialon phosphor ceramic plate. The green luminescence was observed in Ce³⁺ doped Sialon PCP as excited by the 390 nm wavelength. Also, the redshift of emissions was observed when the excitation wavelength was modulated from UV to blue light. The matrix phases and lattice parameters of Sialon PCPs were analyzed by XRD. The co-doping of Y³⁺ cations resulted a composite α/β-Sialon phase while doping with Gd³⁺ produced a higher α-Sialon phase. Higher transparency was observed with Gd³⁺ co-doped sample with greenish-yellow luminescence under blue light excitation. The optical properties of Gd-α-Sialon: Eu²⁺ was also investigated. Moreover, a broadband white light was obtained after placing Gd-α-Sialon: Eu²⁺ on the top of the Gd³⁺/Ce³⁺ doped Sialon as a dual plate under blue LED excitation.

Keywords: Sialon, Transparency, Phosphor ceramic plate, Luminescence