Photoluminescense property of carbon-doped CaAlSiN3:Eu2+

Abstract

We have successfully synthesized the phosphor specimens of [Ca_0.99 Eu²⁺_0.01][Al_1-xSi_1+x]N_3-xC_x (0 ≤ x ≤ 0.6), which were prepared by adding a few SiC compound to the raw materials of CaAlSiN₃:Eu²⁺. Regent-grade chemicals of Ca₃N₂, AlN, Si₃N₄, SiC, EuN were well mixed using a mortar under nitrogen atmosphere. The mixed powder specimens were charged into BN crucibles, which was heated at 1600 °C for 2 h and subsequently at 1800 °C for 4 h under nitrogen pressure of 1 MPa. Diffuse reflectance of [Ca_0.99Eu²⁺_0.01][Al_1-xSi_1+x]N_3-xC_x was, regardless of the x-value, necessarily higher than that of CaAlSiN₃:Eu²⁺, indicating that the doping of carbon atoms into the anion sites in the crystal structure of CaAlSiN₃:Eu²⁺ effectively decreases the reabsorption of photoluminescence.