| 초록 |
Optical properties such as transparency and luminescence of Sialon ceramics doped with different Rare Earth Oxides (REOs) i.e. Eu2O3, Yb2O3, Gd2O3, and Pr2O3 and fabricated with hot press sintering technique have been investigated. From XRD patterns, major α-Sialon phase and minor β-Sialon phase were observed. The transparency measurement of samples of varying thickness from UV to IR region revealed the samples to be translucent in the visible region while transparent in IR region. The luminescence was observed in transmittance mode to investigate the effect of sample thickness. We observed blue, green, yellow and red emissions in Sialon doped with Gd2O3, Yb2O3, Eu2O3, and Pr2O3, respectively. The excitation wavelength for Gd2O3 and Pr2O3 doped samples were in UV region i.e. 280 nm and 270 nm, respectively, whereas, for Yb2O3 and Eu2O3 doped samples were in the blue region (460 nm). Moreover, the fabricated phosphor samples exhibit high hardness around 20 GPa and fracture toughness above 5 MPa.m1/2.
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