Tb3+/Yb3+ co-doped Y2O3 upconversion transparent ceramics: Fabrication and characterization for IR excited green emission

Tb3+/Yb3+ co-doped Y2O3 transparent ceramics were fabricated by vacuum sintering of the pellets (prepared from nanopowders by uniaxial pressing) at 1750 °C for 5 h. Zr4+ and La3+ ions were incorporated in Tb3+/Yb3+ co-doped Y2O3 nanoparticle to reduce the formation of pores which limits the transparency of ceramic. An optical transmittance of ∼80% was achieved in ∼450 to 2000 nm range for 1 mm thick pellet which is very close to the theoretical value by taking account of Fresnel's correction. High intensity luminescence peak at 543 nm (green) was observed in these transparent ceramics under 976 and 929 nm excitations due to Yb-Tb energy transfer upconversion.